Large shaft and method of construction thereof

Abstract

This application provides a large vertical shaft and its construction method, belonging to the field of underground construction technology. The shaft includes: a shaft cylinder composed of multiple ring segments; a ring-shaped top beam located on the outer side of the top of the shaft cylinder; and tension piles positioned below the top ring beam and outside the shaft cylinder along the shaft's depth direction. The bottom of the tension piles is lower than the bottom of the shaft cylinder and is cast integrally with it. The top of the tension piles is fixedly connected to the top ring beam. The horizontal distance between the tension piles and the outer side of the shaft cylinder is less than or equal to the pile diameter. The large vertical shaft and its construction method provided in this application integrate the tension piles, the top ring beam fixed to the ground, and the shaft cylinder into a single structure, capable of resisting the buoyancy caused by groundwater surrounding a deep shaft. This method is suitable for constructing ultra-large and ultra-deep vertical shafts with diameters exceeding 16 meters and depths exceeding 50 meters.

Description

Technical Field

[0001] This application relates to underground construction technology, and more particularly to a large vertical shaft and its construction method. Background Technology

[0002] In urban core areas where land resources are extremely scarce, the available surface space is very limited. Developing deep underground space using shaft technology has become a key solution to overcome land resource constraints and achieve three-dimensional urban development. Mainstream traditional shaft construction methods include open-cut, drill-and-blast, caisson, and drilling methods, but these methods all have significant technical limitations, severely restricting the safe and efficient construction of large-diameter, ultra-deep shafts in urban core areas with soft, water-rich soil.

[0003] Currently, traditional caisson-type vertical shaft structures are typically small to medium diameter, ranging from 4 to 16 meters, and are mainly used in engineering applications such as ventilation shafts, tunnel boring machine launching shafts, and stormwater storage tanks. However, with the increasing demand for underground space in urban development, especially in projects like underground parking lots, the need for large-diameter, ultra-deep vertical shafts is becoming increasingly urgent. However, in urban core areas, especially in soft, water-rich soil strata, traditional methods cannot be used to construct ultra-large and ultra-deep vertical shafts with diameters exceeding 16 meters and depths exceeding 50 meters. On the one hand, as the diameter and depth of the shaft increase, the instability of geological conditions leads to a non-linear increase in the water and soil pressure on the shaft structure, and the buoyancy generated by groundwater also has a significant impact on the stability of the shaft. On the other hand, as the construction depth increases, under the action of a composite stress field, the shaft segment structure not only bears more complex multidimensional loads, but its increased slenderness ratio also easily leads to buckling of the overall structure, while significant stress concentration occurs at the connection points, further exacerbating the risk of structural instability. Furthermore, construction in urban core areas faces strict environmental protection standards, requiring simultaneous compliance with multiple stringent requirements such as low noise control, minimal disturbance construction, and minimization of surface settlement. Summary of the Invention

[0004] To address one of the aforementioned technical deficiencies, this application provides a large vertical shaft and its construction method.

[0005] According to a first aspect of the embodiments of this application, a large vertical shaft is provided, comprising:

[0006] The well shaft is composed of multiple ring segments spliced ​​together.

[0007] The top ring beam is ring-shaped and is located on the outer side of the top of the well shaft.

[0008] The tension piles are installed below the top ring beam and on the outside of the shaft along the depth direction of the shaft. The bottom end of the tension pile is lower than the bottom end of the shaft and is cast into one piece with the bottom end of the shaft. The top end of the tension pile is fixedly connected to the top ring beam. The horizontal distance between the tension pile and the outer side of the shaft is less than or equal to the diameter of the tension pile.

[0009] As described above, the large vertical shaft has a bottom sealing structure at the bottom of the shaft.

[0010] The bottom end of the sealing structure is lower than the bottom end of the well shaft. The sealing structure is formed by pouring concrete and is integrated with the bottom of the well shaft. The sealing structure extends radially outward and is integrated with the tension pile.

[0011] The large vertical shaft described above includes: a cutting edge ring, a launching structure, and standard rings arranged sequentially from bottom to top; the number of standard rings is multiple, arranged sequentially along the depth direction of the shaft; the launching structure includes:

[0012] The initial ring is a ring-shaped structure with an inner and outer surface; the initial ring is located above the cutting edge ring.

[0013] The liner is a ring-shaped structure with an inner side and an outer side. The outer side of the liner contacts and is fixedly connected to the inner side of the initial ring.

[0014] The bottom ring beam is a ring-shaped structure that protrudes radially onto the inner side of the lining.

[0015] As described above, in a large vertical shaft, the inner wall of the initial ring is provided with a tunneling equipment mounting seat for installing tunneling equipment, and the top of the lining is lower than the tunneling equipment mounting seat; the top of the bottom sealing structure extends above the bottom ring beam to be integrated with the launching structure.

[0016] As described above, in a large vertical shaft, the height of the lining along the shaft direction is greater than the thickness of the lining along the radial direction; the thickness of the bottom ring beam along the radial direction is greater than the thickness of the lining along the radial direction.

[0017] As described above, the top ring beam includes a top ring main body and a tensile strength part; the tensile strength part is located outside the top ring main body, extends radially outward to the top of the tensile strength pile, and is connected to the tensile strength pile.

[0018] As described above, in a large vertical shaft, the top surface of the pull-out section is flush with the main body of the top ring, while the bottom surface of the pull-out section is higher than the bottom surface of the main body of the top ring.

[0019] As described above, in a large vertical shaft, the tension piles are divided into two groups, with each group of tension piles arranged in a ring. One group of tension piles is located outside the other group of tension piles; each tension pile in both groups is fixedly connected to the top ring beam.

[0020] As described above, in the large vertical shaft, a set of tension piles on the inner side is located below the inner end of the tension section of the top ring beam, and a set of tension piles on the outer side is located below the outer end of the tension section of the top ring beam.

[0021] As described above, the large vertical shaft has pre-embedded steel bars extending radially within the initial ring, which protrude from the inner side of the initial ring; the inner lining is formed on the inner side of the initial ring by cast-in-place concrete; and the bottom ring beam is formed on the inner side of the inner lining by cast-in-place concrete.

[0022] As described above, the bottom ring beam of the large vertical shaft includes: a bottom ring beam body and a bottom ring beam connecting part. The bottom ring beam body is ring-shaped and has a predetermined distance between it and the inner lining.

[0023] The bottom ring beam connection extends radially and connects the bottom ring beam body and the inner lining; multiple bottom ring beam connections are spaced apart circumferentially.

[0024] As described above, for large vertical shafts, the initial number of rings is at least two, arranged sequentially along the depth direction of the shaft.

[0025] As described above, the initial ring of a large vertical shaft includes a first type of initial ring segment, a second type of initial ring segment, and a third type of initial ring segment, and the segments of each type are spliced ​​together accordingly.

[0026] The inner surface of the first type of initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner surface of the first type of initial ring segment.

[0027] The inner side of the second type of initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner side of the second type of initial ring segment; the upper part of the inner side of the second type of initial ring segment is provided with a tunneling equipment mounting seat for installing tunneling equipment.

[0028] The inner surface of the third type of initial ring segment is provided with a circumferentially extending recess, and the recess is provided with pre-embedded steel bars, which pass through the inner surface of the third type of initial ring segment.

[0029] As described above, the large vertical shaft has three initial rings arranged sequentially along the depth of the shaft; the initial ring at the top layer consists of alternating splicing of first-type and second-type initial ring segments.

[0030] The initial ring located in the middle layer is composed of third-type initial ring segments spliced ​​together circumferentially;

[0031] The initial ring at the bottom layer consists of third-type initial ring segments spliced ​​together circumferentially.

[0032] In the initial ring segment, the lower recess can be aligned and spliced ​​with the upper recess of the third type of initial ring segment.

[0033] As described above, the large vertical shaft also includes:

[0034] A reinforcing ring is disposed between standard rings; the reinforcing ring includes an outer reinforcing ring and an inner reinforcing ring; the outer reinforcing ring is located between the upper and lower standard rings, and the inner reinforcing ring protrudes radially from the inner side of the outer reinforcing ring.

[0035] As described above, in the large vertical shaft, the inner side of the reinforcing outer ring extends inward to form a reinforcing lower ring beam; the reinforcing outer ring and the reinforcing lower ring beam are precast components integrally formed, and the reinforcing lower ring beam is provided with embedded steel bars, the top of which protrudes from the upper surface of the reinforcing lower ring beam;

[0036] A reinforced upper ring beam is formed by casting concrete above the reinforced lower ring beam. The reinforced upper ring beam is fastened to the reinforced lower ring beam by pre-embedded steel bars. The reinforced upper ring beam and the reinforced lower ring beam form the reinforced inner ring in the reinforced ring.

[0037] According to a second aspect of the embodiments of this application, a method for constructing a large vertical shaft is provided, comprising:

[0038] Construct anti-tension piles downwards around the perimeter of the area to be formed into a well shaft, until the bottom of the anti-tension piles is lower than the bottom of the well shaft.

[0039] Open excavation of the foundation pit in the area where the well shaft is to be formed;

[0040] Concrete is poured into the foundation pit to form a top ring beam, which is then connected to the tension piles as a whole.

[0041] Excavate downwards within the area enclosed by the annular top beam and construct the shaft;

[0042] Excavate the strata at the bottom of the well shaft and extend the excavation outwards to near the pull-out piles;

[0043] Concrete is poured into the lower part of the well to form a bottom sealing structure, which is then integrated with the anti-uplift piles and the bottom of the well.

[0044] The shaft construction method described above includes the following steps for constructing the shaft:

[0045] Install the cutting edge ring within the space formed by excavating downwards within the area enclosed by the annular top beam;

[0046] An initial ring is installed on top of the cutting edge ring; the initial ring is a ring-shaped structure with an inner side and an outer side.

[0047] A liner is formed on the inner side of the initial ring; the liner is a ring-shaped structure with an inner side and an outer side, and the outer side of the liner contacts and is fixedly connected to the inner side of the initial ring.

[0048] A bottom ring beam is formed on the inner side of the liner; the bottom ring beam is a ring structure that protrudes radially on the inner side of the liner.

[0049] Multiple standard rings are formed sequentially on top of the initial ring.

[0050] The shaft construction method described above includes a radially extending embedded steel bar within the initial ring, which protrudes from the inner side of the initial ring; an inner lining is formed on the inner side of the initial ring, and a bottom ring beam is formed on the inner side of the inner lining, comprising:

[0051] A reinforcing cage is tied to the pre-embedded reinforcing bars of the initial ring, and a casting formwork is erected outside the reinforcing cage; the shape and size of the reinforcing cage are set in accordance with the inner lining and the bottom ring beam.

[0052] The inner lining and bottom ring beam are formed by casting within the casting template.

[0053] As described above, in the shaft construction method, the inner wall of the initial ring is provided with a tunneling equipment mounting seat for installing tunneling equipment, and the top of the lining is lower than the tunneling equipment mounting seat; the top of the bottom sealing structure extends above the bottom ring beam to be integrated with the launching structure.

[0054] In the shaft construction method described above, the height of the inner lining along the shaft direction is greater than the thickness of the inner lining along the radial direction; the thickness of the bottom ring beam along the radial direction is greater than the thickness of the inner lining along the radial direction.

[0055] In the shaft construction method described above, during the step of constructing the tension piles, the horizontal distance between the tension piles and the shaft to be formed is less than or equal to the diameter of the tension piles.

[0056] The technical solution provided in this application adopts a shaft, a top ring beam, and tensile piles. The shaft is composed of multiple ring segments spliced ​​together. The top ring beam is annular and is located on the outer side of the top of the shaft. The tensile piles are located below the top ring beam and on the outer side of the shaft along the depth direction of the shaft. The bottom end of the tensile pile is lower than the bottom end of the shaft and is cast integrally with the bottom end of the shaft. The top end of the tensile pile is fixedly connected to the top ring beam. The tensile pile, the top ring beam fixed to the stratum, and the shaft are fixedly connected into a whole structure, which can resist the buoyancy caused by groundwater around the shaft with a large depth, thereby improving the reliability of the shaft. Attached Figure Description

[0057] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0058] Figure 1 A cross-sectional view of a shaft provided in an embodiment of this application;

[0059] Figure 2 This is a partial cross-sectional view of a shaft provided in an embodiment of this application;

[0060] Figure 3 A partial structural cross-sectional view of one embodiment of the shaft provided in this application;

[0061] Figure 4 This is a schematic diagram of the assembly of each ring of the starting structure in the shaft provided in an embodiment of this application;

[0062] Figure 5 This is a partial structural schematic diagram of the starting structure in the shaft provided in an embodiment of this application;

[0063] Figure 6 A top view of the starting structure in the shaft provided in an embodiment of this application;

[0064] Figure 7 This is a schematic diagram of the structure of the first type of initial ring segment in a vertical shaft provided in an embodiment of this application;

[0065] Figure 8 This is a schematic diagram of the structure of the second type of initial ring segment in a vertical shaft provided in an embodiment of this application;

[0066] Figure 9 This is a structural schematic diagram of the third type of initial ring segment in a vertical shaft provided in an embodiment of this application;

[0067] Figure 10 This is a schematic diagram of the structure of the cutting edge in the vertical shaft provided in the embodiments of this application;

[0068] Figure 11 This is a schematic diagram of another angle structure of the cutting edge in a vertical shaft provided in an embodiment of this application;

[0069] Figure 12 A cross-sectional view of the cutting edge in a vertical shaft provided in an embodiment of this application;

[0070] Figure 13 This is a schematic diagram of the structure of the reinforced annular segment in the shaft provided in the embodiments of this application;

[0071] Figure 14 This is a schematic diagram of the structure for splicing multiple reinforced ring segments in a vertical shaft, provided in an embodiment of this application.

[0072] Figure 15 This is a schematic diagram of the reinforcing ring in the shaft provided in an embodiment of this application;

[0073] Figure 16 This is a schematic diagram of the structure of the connecting ring in the shaft provided in an embodiment of this application;

[0074] Figure 17 A top view of the top ring beam of the shaft with embedded parts provided in the embodiments of this application;

[0075] Figure 18A schematic diagram of a structure for correcting deviations during the construction of a vertical shaft, provided in an embodiment of this application;

[0076] Figure 19 A top view of the shaft construction process for corrective measures provided in this embodiment of the application;

[0077] Figure 20 This is a schematic diagram of the construction system provided in this application for constructing a vertical shaft.

[0078] Figure label:

[0079] 1-Top ring beam; 11-Top ring main body; 12-Pull-out section; 13-First embedded part; 14-Second embedded part; 15-Ground anchor component;

[0080] 2-Standard ring;

[0081] 3-Initial structure; 31-Initial ring; 311-First type initial ring segment; 312-Second type initial ring segment; 313-Third type initial ring segment; 314-Recessed portion; 315-Tunneling equipment mounting base; 32-Inner lining; 33-Bottom ring beam; 331-Bottom ring beam connection; 332-Bottom ring beam main body;

[0082] 4-Cutting edge ring; 41-Cutting edge; 42-Steel strand through hole; 43-Wire groove; 44-Monitoring groove; 45-Grouting stop plate; 46-Grouting hole; 47-Segment connection hole;

[0083] 5-Pull-out piles;

[0084] 6- Bottom sealing structure;

[0085] 7-Reinforcing ring; 71-Reinforcing ring segment; 72-Reinforcing lower ring beam segment; 721-Reinforcing connection; 722-Reinforcing ring section; 73-Reinforcing upper ring beam; 74-Anchor bolt hole; 75-Groove;

[0086] 8-Connecting ring; 81-Connecting ring segment; 82-Boss;

[0087] 91-Anchor bolt; 92-Embedded reinforcing bar;

[0088] 101-Tunneling equipment; 102-Main unit hoisting system. Detailed Implementation

[0089] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0090] In urban core areas where land resources are highly scarce, surface space is extremely limited. Utilizing shaft technology to develop deep underground space has become a crucial way to overcome urban land resource bottlenecks and promote the three-dimensional development of cities. Shaft structures have a wide range of applications, commonly found in ventilation shafts, shield tunneling launching shafts, storm water storage tanks, underground storage facilities, and underground multi-level parking garages, among other engineering scenarios. Traditional shaft construction methods mainly include drill-and-blast, drilling, and caisson methods. Drill-and-blast methods are technically mature, but they pose significant safety risks, are slow, and cause substantial environmental disturbance, noise, and dust pollution. Drilling is a non-explosive, mechanized tunneling method with strong adaptability to geological formations, but it suffers from limitations such as low efficiency in rock breaking and slag removal, and low technological maturity. Traditional caisson methods have limited sinking depths; in water-rich strata, dewatering or drainage measures are required, and problems such as sudden sinking, over-sinking, and deviation are prone to occur, significantly impacting the surrounding environment. Therefore, due to the limitations of current shaft construction technology, the dimensions of traditional urban shaft structures are difficult to break through, with diameters generally less than 16 meters and depths less than 50 meters, which cannot meet the growing demand for deep and large shaft structures in the process of urban underground space development.

[0091] The construction of deep vertical shafts within limited urban spaces presents a series of severe technical challenges. First, as shafts expand in diameter and depth, the uncertainty of geological conditions leads to a non-linear increase in soil and water pressure on the shaft structure. This results in more complex multidimensional loads, an increased slenderness ratio which raises the risk of overall buckling, and significant stress concentration at joints, further exacerbating the possibility of structural instability. Furthermore, as shafts deepen, the buoyancy of groundwater significantly impacts their stability. Second, the complex urban construction environment and limited site area necessitate minimizing disturbance to the surrounding soil and strictly controlling ground settlement, especially in water-rich, soft soil areas where drainage must be minimized to ensure soil stability. Efficiency must be improved, construction time shortened to save costs, and the surrounding area restored to normal as quickly as possible. Noise and pollution must be reduced to mitigate environmental impact. Construction safety must be ensured, particularly under conditions of large excavation sections and deep excavation, with effective prevention and control of risks such as shaft tilting and sudden subsidence, and real-time dynamic monitoring.

[0092] To overcome the limitations of constructing large vertical shafts within limited urban spaces, this application provides a large vertical shaft and its construction method. This method enables the construction of large vertical shafts with diameters exceeding 23 meters and depths exceeding 50 meters in complex and environmentally sensitive areas. It has significant advantages such as construction safety, high efficiency, and minimal environmental impact, providing reliable technical support for the development of deep underground space. Moreover, it can solve the impact of buoyancy generated by groundwater on the vertical shaft.

[0093] First, the structure of the shaft will be explained:

[0094] like Figures 1 to 3As shown, the vertical shaft provided in this embodiment includes: a shaft, a top ring beam 1, and tension piles 5. The shaft, composed of prefabricated segments assembled into a multi-ring structure, is the main structure of the vertical shaft and is constructed underground.

[0095] The top ring beam 1 is annular and is located on the outer side of the top of the shaft. The inner side of the top ring beam 1 encloses the vertical shaft installation space, within which the shaft is installed. Specifically, the topmost ring segment in the shaft is located below the top ring beam 1, and all other ring structures are located directly below the topmost segment. The top ring beam 1 contains embedded fixing seats for connection to the main hoisting system and the shaft hoisting system.

[0096] Specifically, the top ring beam 1 can be a concrete + steel composite structure, cast in one go. Pre-embedded fixing seats for components such as the well shaft lifting system and the main unit lifting system are embedded in the top ring beam 1, serving as the core load-bearing structure during construction. Simultaneously, before the construction of the top ring beam 1, to reduce the risk of uneven settlement during construction and improve the soil bearing capacity, triaxial mixing piles are used to reinforce the foundation, thereby enhancing the overall bearing capacity of the top ring beam and the foundation.

[0097] The tension pile 5 is set below the top ring beam 1 and outside the shaft along the depth direction of the shaft. The bottom end of the tension pile 5 is lower than the bottom end of the shaft and is cast into one piece with the bottom end of the shaft. The top end of the tension pile 5 is fixedly connected to the top ring beam 1, so that the top ring beam 1, tension pile 5 and shaft are fixedly connected into one structure, which can resist the buoyancy caused by the groundwater outside the shaft with a large depth, thereby improving the reliability of the shaft.

[0098] The technical solution provided in this embodiment employs a shaft, a top ring beam, and tensile piles. The shaft is composed of multiple ring segments spliced ​​together. The top ring beam is annular and located on the outer side of the top of the shaft. The tensile piles are located below the top ring beam and on the outer side of the shaft along the depth direction of the shaft. The bottom of the tensile piles is lower than the bottom of the shaft and is cast integrally with the bottom of the shaft. The top of the tensile piles is fixedly connected to the top ring beam. By fixing the tensile piles, the top ring beam fixed to the stratum, and the shaft into a single structure, the structure can resist the buoyancy caused by groundwater around the shaft at greater depths, thereby improving the reliability of the shaft.

[0099] Based on the above technical solution, this embodiment provides a scheme for connecting the tension pile 5 to the well shaft, wherein a bottom sealing structure 6 is provided at the lower part of the well shaft. The bottom end of the bottom sealing structure 6 is lower than the bottom end of the well shaft. The bottom sealing structure 6 is formed by pouring concrete and is integrated with the bottom of the well shaft. The bottom sealing structure 6 extends radially outward and is integrated with the tension pile 5.

[0100] Traditional solutions are suitable for constructing shafts less than 16 meters deep. However, as the shaft depth exceeds 16 meters, the buoyancy of groundwater becomes increasingly significant, and traditional solutions lack effective solutions to address this issue. This application integrates the anti-tension pile 5, the top ring beam 1, and the bottom sealing structure 6 into a single unit. This not only ensures the quality of the shaft bottom sealing but also improves the shaft's anti-buoyancy capacity, thereby enhancing the shaft's strength and reliability. It is suitable for constructing ultra-large and ultra-deep shafts with diameters exceeding 16 meters and depths exceeding 50 meters, and exhibits good resistance to non-linearly increasing water and soil pressure.

[0101] This embodiment also provides an implementation method for a shaft: the shaft includes, from bottom to top, a cutting edge ring 4, a launching structure 3, and standard rings 2. The cutting edge ring 4 is located at the bottom of the shaft, the launching structure 3 is located above the cutting edge ring 4, and multiple standard rings 2 are arranged sequentially above the launching structure 3 along the depth direction of the shaft. The standard rings 2, launching structure 3, and cutting edge ring 4 are all annular structures, forming the shaft. A tunneling equipment mounting base for installing tunneling equipment is pre-embedded on the launching structure 3.

[0102] Specifically, the inner side of the top ring beam 1 forms a vertical shaft installation space, and the standard ring 2, the launching structure 3, and the cutting edge ring 4 are all installed within this vertical shaft installation space inside the top ring beam 1. Specifically, the topmost standard ring 2 is located below the top ring beam 1, and all other ring structures are located directly below the topmost standard ring 2.

[0103] The bottom of the tension pile 5 is lower than the cutting edge ring 4. The tension pile 5 is located outside the standard ring 2, the starting structure 3 and the cutting edge ring 4, and the top ring beam 1 is located above the tension pile 5 and is fixedly connected to the tension pile 5.

[0104] The bottom sealing structure 6 is fixedly installed in the stratum below the cutting edge ring 4. The bottom sealing structure 6 extends radially outward to be tightly connected with the anti-tension pile 5. The bottom sealing structure 6, the anti-tension pile 5 and the top ring beam 1 are connected into an integrated structure. On the one hand, it can achieve the function of sealing the bottom of the well, and on the other hand, it can increase its own weight, which is conducive to resisting the buoyancy of groundwater and is more suitable for deep vertical wells.

[0105] The bottom sealing structure 6 is a fixed concrete layer formed by injecting anti-segregation concrete into the space created by excavating outward from the bottom of the shaft into the stratum below the launching structure 3. Specifically, after the shaft is constructed, excavation is carried out into the stratum below the cutting edge ring 4 and extended outward to near the tension pile 5. Then, concrete guide pipes are laid, and anti-segregation concrete is injected into the excavated area. After the concrete solidifies, it serves as a fixed concrete layer and is connected to the tension pile 5 as an integral structure. The tension pile 5 passes through the fixed concrete layer, and the bottom end of the tension pile 5 is lower than the fixed concrete layer.

[0106] Then, a waterproof layer is laid on top of the fixed concrete layer, and a base slab is formed by pouring concrete on top of the waterproof layer. The waterproof layer, the base slab, and the fixed concrete layer together form the bottom sealing structure.

[0107] During construction, firstly, anti-tension piles are installed downwards around the location where the vertical shaft will be formed, with the depth of the anti-tension piles exceeding the depth of the shaft shaft. Next, an open-cut foundation pit is excavated at the location of the vertical shaft to the design elevation of the bottom of the top ring beam. Then, the top ring beam is cast in place within the foundation pit and fixedly connected to the anti-tension piles. Next, the shaft hoisting system and the main hoisting system are installed and connected to the pre-embedded fixing seats on the top ring beam. The cutting edge ring is installed and connected to the shaft hoisting system via steel strands. The launching structure is then constructed above the cutting edge ring. The foundation pit is excavated further until the space required for the cutting arm of the tunneling equipment to operate is met. Finally, the assembled and debugged tunneling equipment is launched. The excavation equipment is hoisted into the foundation pit and connected to the pre-embedded fixing seat of the launching structure and the main hoisting system. The excavation equipment vertically excavates the strata, sequentially carrying out shaft sinking and standard ring segment lifting and installation until the designed depth of the vertical shaft is reached. The excavation equipment uses a mud circulation mode for muck removal, enabling underwater excavation without dewatering within the shaft. During construction, thixotropic mud is injected into the shaft wall through pre-set grouting holes in the standard ring segments to reduce friction and maintain the stability of the external rock strata. A sealing structure is formed inside the launching structure and below the cutting edge ring, fixedly connected to the pull-out piles and covering the launching structure. The mud inside the shaft is then discharged.

[0108] If the shaft is found to be tilted during construction, the shaft lifting device can be used to dynamically adjust the lifting force and the amount of steel strand laid. Combined with the over-excavation method at the working face, the shaft angle can be adjusted in time to avoid the consequences of sinking difficulties, shaft wall damage or position deviation caused by tilting.

[0109] The aforementioned technical solution overcomes the problems of large excavation area and large workload associated with open-cut methods; it also overcomes the high safety risks and severe dust pollution associated with drill-and-blast methods; and it solves the problem of easy shaft tilting and difficulty in correction that traditional caisson methods cannot address. It is particularly suitable for constructing large-diameter, ultra-deep vertical shafts in soft, water-rich soil strata and urban core areas. Furthermore, the combination of anti-tension piles with top ring beams and bottom sealing structures can resist the buoyancy of groundwater, further enhancing its suitability for the construction of deep vertical shafts.

[0110] like Figures 4 to 6 As shown, the starting structure 3 includes: an initial ring 31, an inner liner 32, and a bottom ring beam 33.

[0111] The initial ring 31 is set on top of the cutting edge ring 4. The initial ring 31 is a ring-shaped structure with an inner and an outer surface. A tunneling equipment mounting base is pre-embedded on the initial ring 31. The tunneling equipment is hoisted into the shaft and installed on the pre-embedded tunneling equipment mounting base, enabling it to excavate the strata below the initial ring 31.

[0112] The inner liner 32 has a ring-shaped structure with an inner side and an outer side. The outer side of the inner liner 32 contacts and is fixedly connected to the inner side of the initial ring 31.

[0113] The bottom ring beam 33 is a ring structure that protrudes radially onto the inner side of the liner 32.

[0114] The launching structure 3 consists of an initial ring 31, an inner liner 32, and a bottom ring beam 33. The initial ring 31 and the bottom ring beam 33 are inner and outer rings, forming a double ring shape in the radial direction, which can improve the radial support force of the shaft, thereby enhancing the overall rigidity and integrity of the bottom of the shaft.

[0115] During construction, the top ring beam 1 is formed first, then the cutting foot ring 4 is installed, followed by the launching structure 3, and then the standard ring 2 is installed in sequence. The launching structure 3, as the initial installation structure, can bear the water pressure inside and outside the well and the working support force of the tunneling equipment during subsequent construction.

[0116] In addition, the starting structure 3 is a double-ring shape, which can eliminate stress concentration at the connection point, effectively suppress the buckling and fracture risks of ultra-deep shafts, and improve shaft stability. On the one hand, it can install and support the tunneling equipment, and on the other hand, it can resist the force of the surrounding soil layer and resist shaft head convergence. It is suitable for constructing ultra-large and ultra-deep shafts with a diameter of more than 16 meters and a depth of more than 50 meters. It also has a good bearing capacity for nonlinearly increasing water and soil pressure, and can also bear the complex soil load of deep and large shafts, thus solving the problem of shaft buckling.

[0117] Based on the above, the technical solution provided in this embodiment can construct deep and large-diameter vertical shafts in densely populated cities, exhibiting high reliability. Furthermore, its excavation process does not require a large area, thus reducing the impact on residents' travel. For example, underground parking garages can be constructed using the technical solution provided in this embodiment, greatly improving the parking difficulties in densely populated cities, reducing road traffic pressure, and minimizing traffic congestion caused by roadside parking.

[0118] Based on the above technical solution, a specific implementation method is as follows: the height of the inner lining 32 along the vertical shaft direction is greater than the radial thickness of the inner lining 32, which increases the contact area between the inner lining 32 and the initial ring, thereby improving the connection strength. The radial thickness of the bottom ring beam 33 is greater than the radial thickness of the inner lining 32, increasing the radial dimension and thus improving the radial compressive strength.

[0119] The inner wall of the initial ring 31 is equipped with a tunneling equipment mounting base, and the top of the inner lining 32 is lower than the tunneling equipment mounting base. The top of the sealing structure 6 extends above the bottom ring beam 33. Specifically, the height of the fixed concrete layer extends above the bottom ring beam 33, covering the bottom ring beam 33. The fixed concrete layer, the bottom ring beam 33, and the inner lining 32 are cast as one piece, which can further increase the connection stiffness between the fixed concrete layer and the initial structure.

[0120] Furthermore, the horizontal distance between the tension pile 5 and the outer side of the well shaft is less than or equal to the pile diameter of the tension pile 5, which enables higher connection and support strength. One embodiment is as follows: the top ring beam 1 includes a top ring main body 11 and a tension portion 12. The tension portion 12 is located outside the top ring main body 11, extending radially outward to above and connected to the tension pile 5. The top ring main body 11 and the tension portion 12 can be formed by casting concrete in place within the foundation pit and are fixedly connected to the tension pile 5.

[0121] One embodiment is as follows: the top surface of the tension-resistant portion 12 is flush with the main body portion 11 of the top ring, and the bottom surface of the tension-resistant portion 12 is higher than the bottom surface of the main body portion 11 of the top ring, so that a stepped structure is formed between the tension-resistant portion 12 and the main body portion 11 of the top ring. The tension-resistant pile 5 is located below the tension-resistant portion 12, and the tension-resistant pile 5 can be limited by the stepped structure.

[0122] There are three or more tension piles 5, arranged in a ring around the outside of the well shaft. Each tension pile 5 is spaced apart circumferentially. For example... Figure 3 As shown, the portion between each tension pile 5 is a geological structure.

[0123] Alternatively, another approach is to divide the tension piles 5 into two groups, with each group's tension piles 5 arranged in a ring. One group of tension piles 5 is located outside the other group, forming a concentric ring. Each tension pile 5 in both groups is fixedly connected to the top ring beam 1, and each tension pile 5 is also fixedly connected to the bottom sealing structure 6. By connecting multiple tension piles 5 arranged in a concentric ring to the top ring beam 1 and the bottom sealing structure 6 respectively, the strength and anti-buoyancy performance of the shaft can be further improved. In this scheme, the horizontal distance between the tension piles and the shaft to be formed specifically refers to the horizontal distance between the surface of the inner group of tension piles 5 facing the shaft and the shaft itself. This horizontal distance is less than or equal to the diameter of the tension pile 5.

[0124] One specific implementation method involves two sets of tension piles 5. The inner set of tension piles 5 is positioned below the inner end of the tension-resistant portion 12 of the top ring beam, wedged onto the outer side of the stepped structure formed between the main body 11 of the top ring beam and the tension-resistant portion 12. The outer set of tension piles 5 is positioned below the outer end of the tension-resistant portion 12. The two sets of tension piles 5 are arranged radially at intervals and respectively on both sides of the tension-resistant portion 12, which improves the force transmission performance and makes the force distribution more balanced.

[0125] The aforementioned tension piles can be precast piles, driven directly into the ground; or they can be formed by drilling holes below the ground and pouring concrete. Tension piles can be vertical structures with identical cross-sectional shape and dimensions throughout.

[0126] Another approach involves the underground portion of the tension pile protruding radially outwards to form a disc-shaped or toothed structure, increasing the vertical resistance between the pile and the soil. For example, a bored pile is drilled to the designed depth, and then a jacking machine is lowered into the hole. A hydraulic system extends the telescopic arm of the jacking machine outwards, compressing the surrounding soil and widening it into a radially protruding shape, forming an enlarged cavity resembling a disc or gear. A reinforcing cage is then lowered into the hole and concrete is poured. The resulting tension pile includes a vertically extending portion and a radially protruding disc-shaped or toothed portion.

[0127] Based on the above technical solution, the starting structure is further described as follows: An embedded steel bar 92 extending radially is provided inside the initial ring 31, and the embedded steel bar 92 protrudes from the inner side of the initial ring 31. The inner lining 32 is formed on the inner side of the initial ring 31 by cast-in-place concrete, and the bottom ring beam 33 is formed on the inner side of the inner lining 32 by cast-in-place concrete.

[0128] The inner lining 32 is cast together with the bottom ring beam 33. The height of the inner lining 32 along the vertical shaft direction is greater than the thickness of the inner lining 32 along the radial direction, so that the inner lining 32 and the initial ring 31 have a larger contact area, which can enhance the strength and reliability of the connection between the bottom ring beam 33 and the initial ring 31.

[0129] The bottom ring beam 33 includes a bottom ring beam connecting portion 331 and a bottom ring beam body 332. The bottom ring beam body 332 is annular and has a predetermined distance between it and the inner liner 32. The bottom ring beam connecting portion 331 extends radially and connects the bottom ring beam body 332 and the inner liner 32. Multiple bottom ring beam connecting portions 331 are arranged circumferentially, and the gap between adjacent bottom ring beam connecting portions 331 serves as a cable passage space for passing steel strands or other cables.

[0130] This embodiment provides a way for the cutting edge ring 4 to cooperate with the starting structure 3: the outer side of the cutting edge ring 4 extends along the depth direction of the vertical shaft; in the direction from top to bottom, the distance between the inner side of the upper part of the cutting edge ring 4 and the outer side of the cutting edge ring 4 is equal; the distance between the inner side of the lower part of the cutting edge ring 4 and the outer side of the cutting edge ring 4 gradually decreases, which is equivalent to the lower part of the cutting edge ring 4 being pointed, which is conducive to insertion into the formation.

[0131] The outer side of the bottom end of the liner 32 extends downward to fit against the upper part of the inner side of the cutting edge ring 4, so that the liner 32 and the cutting edge ring 4 are also connected into an integral structure, further improving the radial bearing capacity of the wellbore.

[0132] Furthermore, the distance between the inner side of the bottom end of the inner liner 32 and the outer side of the inner liner 32 gradually decreases, and the inner side of the bottom end of the inner liner 32 aligns with and is flush with the inner side of the lower part of the cutting edge ring 4. This makes the bottom end of the inner liner 32 also pointed, and its inclination angle is consistent with that of the cutting edge ring 4, which can increase the area for insertion into the formation, thereby improving the strength of the connection between the wellbore and the formation.

[0133] The number of initial rings 31 can be at least two (one for installing the tunneling machine and the other for connecting the bottom ring beam), arranged sequentially along the direction of shaft extension. Each initial ring 31 consists of multiple initial ring segments spliced ​​together circumferentially, and each initial ring segment is provided with pre-embedded steel bars 92. The joints of the initial ring segments in adjacent initial rings 31 are staggered.

[0134] In this embodiment, there are three initial rings 31, arranged sequentially along the shaft extension direction. The inner lining 32 is annular, with cast-in-place concrete formed on the inner side of the initial rings 31. The bottom ring beam 33 is annular, with cast-in-place concrete formed on the inner side of the inner lining 32. The top of the bottom ring beam 33 is lower than the top of the top initial ring 31 and located below the tunneling equipment mounting base, while the bottom of the bottom ring beam 33 is higher than the bottom of the bottom initial ring 31. For example, in one specific manner, the radial projection of the bottom ring beam 33 is located on the initial ring 31 of the middle layer, that is, the height of the bottom ring beam 33 is the same as the height of the middle initial ring 31 among the three initial rings 31.

[0135] There are three initial rings 31, which are arranged from top to bottom as the top initial ring, the middle initial ring, and the bottom initial ring. The top of the inner liner 32 is lower than the top of the top initial ring, and the outer side of the bottom end of the inner liner 32 is in contact with the inner side of the initial ring 31.

[0136] Based on the above technical solution, the initial ring 31 includes a first type of initial ring segment 311, a second type of initial ring segment 312 and a third type of initial ring segment 313, and the various types of initial ring segments are spliced ​​together accordingly.

[0137] The first type of initial annular segment 311 has a circumferentially extending recess 314 on its inner surface, and the recess 314 is provided with a pre-embedded reinforcing bar 92, which protrudes from the inner surface of the first type of initial annular segment 311. Figure 7 As shown in the figure, the inner side of the first type of initial ring segment 311 is provided with a recess 314 extending in the circumferential direction at the middle and lower parts. Each recess 314 is provided with a pre-embedded steel bar 92, which passes through the inner side of the first type of initial ring segment 311.

[0138] The inner surface of the second type of initial annular segment 312 is provided with a circumferentially extending recess 314, and the recess 314 is provided with a pre-embedded steel bar 92, which protrudes from the inner surface of the second type of initial annular segment 312. For example... Figure 8 As shown in the figure, the inner side of the second type of initial ring segment 312 is provided with a recess 314 extending in the circumferential direction at the middle and lower parts. Each recess 314 is provided with a pre-embedded steel bar 92, which passes through the inner side of the second type of initial ring segment 312. The upper part of the inner side of the second type of initial ring segment 312 is pre-embedded with a tunneling equipment mounting base 315.

[0139] The inner surface of the third type of initial annular segment 313 is provided with a circumferentially extending recess 314, and the recess 314 is provided with a pre-embedded steel bar 92, which protrudes from the inner surface of the third type of initial annular segment 313. For example... Figure 9 As shown in the figure, the inner side of the third type of initial ring segment 313 is provided with a recess 314 extending in the circumferential direction at the upper, middle and lower parts. Each recess 314 is provided with a pre-embedded steel bar 92, which passes through the inner side of the third type of initial ring segment 313.

[0140] The aforementioned first type of initial ring segment 311, second type of initial ring segment 312, and third type of initial ring segment 313 are spliced ​​together to form three initial rings 31. Reinforcing bars 92 are used for binding, and formwork is erected and concrete is poured to form the inner lining 32 and the bottom ring beam 33. The second type of initial ring segment 312 can be configured according to the installation location of the tunneling equipment to meet installation requirements.

[0141] One implementation is as follows: the initial ring 31 at the top layer is formed by alternating splicing of a first type of initial ring segment 311 and a second type of initial ring segment 312; the initial ring 31 at the middle layer is formed by splicing of a third type of initial ring segment 313 along the circumferential direction; the initial ring 31 at the bottom layer is formed by splicing of a third type of initial ring segment 313 along the circumferential direction.

[0142] In the first type of initial annular segment 311 and the second type of initial annular segment 312, the lower recess 314 can be aligned and spliced ​​with the upper recess 314 of the third type of initial annular segment 313. Specifically, in the first type of initial annular segment 311 and the second type of initial annular segment 312, the depth of the lower recess 314 is equal to the depth of the upper recess 314 of the third type of initial annular segment 313.

[0143] Furthermore, in the third type of initial ring segment 313, the width of the middle recess 314 is twice the width of the upper recess 314 and also twice the width of the lower recess 314, so that the width of the recess of each segment itself is basically equal to the width of the ring recesses spliced ​​together, thereby achieving stress balance and facilitating the layout of a similar number of pre-embedded steel bars 92 to facilitate the cast-in-place formation of the inner lining 32.

[0144] Grouting holes are provided in some segments of the initial ring 31 to inject thixotropic mud into the space between the well casing and the surrounding soil. After the well casing construction is completed, cement grout can be injected into the space between the well casing and the surrounding soil through the grouting holes to replace the thixotropic mud and integrate the well casing with the surrounding rock.

[0145] Based on the above technical solution, this embodiment also provides an implementation method for the blade foot ring 4:

[0146] like Figures 10 to 12 As shown, the cutting edge ring 4 is composed of multiple cutting edges 41 spliced ​​together circumferentially. The cutting edges 41 are made of steel and have high hardness, which is conducive to insertion into the strata. In addition, the sharp corner structure at the bottom of the steel cutting edge can concentrate pressure to cut into the soil or rock layer, reduce the friction and end resistance during shaft sinking, and make sinking smoother.

[0147] During the shaft sinking process, in order to reduce the friction between the shaft wall and the outer soil, and at the same time maintain the stability of the soil on the outer side of the shaft wall to ensure the smooth sinking of the shaft, it is necessary to prepare thixotropic mud and inject it into the outer side of the shaft wall.

[0148] Furthermore, the radial thickness of the cutting edge ring 4 is greater than that of the initial ring 31; the inner surface of the cutting edge ring 4 is flush with the inner surface of the initial ring 31, and the outer surface of the cutting edge ring 4 extends beyond the outer surface of the initial ring 31. During construction, a mud space is formed between the wellbore above the outer surface of the cutting edge ring 4 and the surrounding formation. The outer surface of the cutting edge ring 4 extending beyond the outer surface of the initial ring 31 can stop the mud above.

[0149] Furthermore, a slurry stop plate is provided on the lower outer side of the cutting edge 41, protruding further outward from the outer side of the initial ring 31. The slurry stop plates of each cutting edge 41 are joined together to form a ring-shaped structure for stopping the mud, which can prevent thixotropic mud from entering the wellbore from below and mixing with the existing mud. The slurry stop plate 45 can be made of rubber, which has a certain deformation capacity and a certain wear resistance.

[0150] The cutting edge 41 has a steel strand through hole 42. One end of the steel strand through hole 42 extends to the upper outer surface of the cutting edge 41, and the other end extends to the lower inner surface of the cutting edge 41. Specifically, a wire-passing groove 43 is formed on the upper outer surface of the cutting edge 41, and a wire-passing groove 43 is also formed on the lower inner surface of the cutting edge 41. The bottom wall of the wire-passing groove 43 has a steel strand through hole 42. The steel strand enters from the upper end of the steel strand through hole 42 and exits from the lower end and is anchored. The steel strand is used to connect to the wellbore hoisting system, which can be installed on the ground.

[0151] A monitoring slot 44 is also provided on the lower inner side of the cutting edge 41 for installing an earth pressure gauge to measure the soil pressure in front of the cutting edge 41, thus facilitating the determination of the stability of the excavation face. The earth pressure gauge is inserted into the monitoring slot 44 to avoid mechanical damage during the sinking process; and it can be easily disassembled and replaced later without affecting the construction schedule. The monitoring slot 44 is located below the lower outlet of the steel strand through hole 42.

[0152] The lower inner side of the cutting edge 41 is provided with a grouting hole 46. A grouting pipe passes through the grouting hole 46 to inject cement grout into the outside of the well casing after the well casing construction is completed. For example... Figure 12 As shown, Figure 12 for Figure 11 The cross-sectional view at position AA shows that the material inside the cutting edge 41 is cement grout. Figure 12 The grout stop plate 45 was not shown in the text.

[0153] The top surface of the cutting edge 41 is provided with a segment connection hole 47 for connecting with adjacent ring segments, specifically corresponding to the initial ring segment at the top. The cutting edge 41 is a prefabricated component and can be connected to adjacent ring segments by pre-embedded bolts.

[0154] Based on the above, connecting holes are provided on the end faces of the starting structure 3 and the standard ring 2, and adjacent rings are connected by bolts. Each ring segment can be a prefabricated component, connected by bolts.

[0155] The cutting edge 41 has a cavity for filling concrete, and stiffening ribs are provided inside the cavity. After the cutting edge ring 4 is assembled, concrete is backfilled into the cavity of the cutting edge 41 to give the cutting edge 41 a certain weight. The backfilled concrete must not affect the steel strand.

[0156] As the construction depth increases, the slenderness ratio of the shaft increases. Furthermore, during operation, the earth pressure and groundwater pressure vary with time and season, which can lead to different sizes of opening at the joints of the shaft. This can cause buckling of the overall structure, and stress concentration is more likely to occur at the connection points, resulting in instability of the shaft structure.

[0157] Based on the above technical solution, a reinforcing ring 7 is also used, positioned between the standard rings 2. Specifically, after installing a predetermined number of standard rings 2, the reinforcing ring 7 is installed, and then the standard rings 2 are installed again. The reinforcing ring 7 includes an outer reinforcing ring and an inner reinforcing ring. The outer reinforcing ring is located between the upper and lower standard rings 2, specifically directly above or below the standard rings 2. The inner reinforcing ring protrudes from the inside of the outer reinforcing ring and is fixedly connected to it. One approach is to arrange one reinforcing ring 7 for every predetermined depth the shaft descends, which can prevent the overall buckling and instability of the shaft.

[0158] By reinforcing the outer ring and the inner ring to form a double-ring structure, the two rings work together to resist the horizontal pressure of the formation and prevent the shaft from buckling and becoming unstable. This structure is especially suitable for shafts with greater depth and diameter.

[0159] In addition, anchor bolt holes are provided on the reinforcing ring 7, extending radially. After the shaft is constructed, the anchor bolt holes are drilled through, and anchor bolts 91 are inserted outward from the anchor bolt holes into the formation. Grouting reinforcement is then carried out, which can further improve the structural quality and reliability of the deep vertical shaft during its operation.

[0160] Based on the above technical solutions, this embodiment provides an implementation method for the reinforcing ring 7: as follows Figures 13 to 16 As shown, the reinforcing outer ring in the reinforcing ring 7 is composed of multiple arc-shaped reinforcing ring segments 71 spliced ​​together circumferentially, and the reinforcing ring segments 71 and the standard ring segments are staggered at the joint.

[0161] The inner side of the reinforcing outer ring extends inward to form a reinforcing lower ring beam. Specifically, the inner side of the reinforcing ring segment 71 extends inward to form a reinforcing lower ring beam segment 72. The reinforcing lower ring beam segments 72 on each reinforcing ring segment 71 are joined together to form a ring-shaped reinforcing lower ring beam.

[0162] The reinforcing outer ring and the reinforcing lower ring beam are precast components formed as one piece, specifically the reinforcing ring segment 71 and the reinforcing lower ring beam segment 72 are precast components formed as one piece. The reinforcing lower ring beam is provided with vertical embedded steel bars 92, the top of which protrudes from the upper surface of the reinforcing lower ring beam.

[0163] After the reinforcement ring segments 71 are assembled, concrete is integrally poured on top of the reinforcement lower ring beam of each reinforcement ring segment 71 to form the reinforcement upper ring beam 73. The reinforcement upper ring beam 73 is an integral structure and is fastened to the reinforcement lower ring beam through pre-embedded steel bars. The reinforcement upper ring beam and the reinforcement lower ring beam form the reinforcement inner ring in the reinforcement ring 7.

[0164] In this embodiment, the reinforced lower ring beam piece 72 constituting the reinforced lower ring beam includes: a reinforced connecting portion 721 and a reinforced ring portion 722. The reinforced connecting portion 721 is disposed between the reinforced ring portion 722 and the reinforced outer ring, and multiple reinforced connecting portions 721 are spaced apart. The gap between adjacent reinforced connecting portions 721 serves as a cable passage space for passing through the steel strands or other cables of the main unit lifting system.

[0165] Furthermore, each reinforcing ring segment 71 of the reinforcing outer ring is provided with an anchor bolt hole 74 extending radially. The anchor bolt hole 74 is a blind hole, which is drilled through before the anchor bolt is inserted.

[0166] The reinforcing ring 7 can be directly connected between the upper and lower standard rings 2, or it can be connected via a connecting ring 8. Specifically, the connecting ring 8 is positioned between the reinforcing ring 7 and the standard ring 2. It serves two purposes: firstly, to connect the reinforcing ring 7 and the standard ring 2; and secondly, to transmit the shear force between the reinforcing ring 7 and the connecting ring 8. This provides radial restraint between the reinforcing ring 7 and the standard ring 2, preventing radial relative displacement and relative sliding or misalignment between the segments, thus ensuring the upper and lower segments form a unified whole and improving the wellbore strength.

[0167] like Figure 16 As shown, one embodiment is as follows: a boss 82 is provided at one end of the connecting ring 8 that is connected to the reinforcing ring 7. Correspondingly, a groove 75 for accommodating the boss 82 is provided at the end of the reinforcing outer ring (specifically, the end of the reinforcing ring segment 71). The boss 82 in the connecting ring 8 is inserted into the groove of the reinforcing ring segment 71, thereby achieving radial positioning of the two.

[0168] The connecting ring 8 comprises multiple connecting ring segments 81 joined together circumferentially, with a boss 82 at one end of each connecting ring segment 81. The cross-section of the boss 82 can be rectangular or isosceles trapezoidal. Correspondingly, the cross-section of the groove on the reinforcing ring segment 71 is an isosceles trapezoid.

[0169] Standard ring 2 is constructed by splicing multiple standard ring segments circumferentially. The joints between connecting ring segments 81 are staggered vertically from the joints of adjacent standard ring segments and also from the joints of reinforcing ring segments 71. Standard ring segments may be equipped with grouting holes, through which thixotropic mud can be injected between the well casing and the outer soil to reduce backwall friction and maintain the stability of the soil outside the well casing. After the well casing construction is completed, cement grout can be injected from bottom to top between the well casing and the outer soil through the grouting holes to replace the thixotropic mud, thus integrating the well casing with the external soil.

[0170] One implementation is as follows: the reinforcing ring 7 is provided with connecting rings 8 at both the top and bottom, and the two ends of the reinforcing outer ring (specifically the reinforcing ring tube 71) are provided with grooves 75, which are respectively connected to the protrusions 82 of the connecting ring tube 81 on both sides. The connecting rings 8 and the reinforcing ring 7 can also be connected by bolts to improve the connection strength.

[0171] An expansion sealing rubber ring is also provided between the boss 82 of the connecting ring 8 and the groove 75 of the reinforcing ring 7, which can achieve a better waterproof effect and prevent groundwater from seeping into the well.

[0172] The shaft described above mainly utilizes anti-tension piles 5, bottom sealing structure 6, and top ring beam 1 for fixed connection, which can enhance the overall integrity of the shaft and the connection strength with the surrounding soil, improve the shaft's anti-buoyancy capacity, ensure the stability of the structure in deep water-rich environments, and significantly improve the bearing capacity and safety margin of ultra-large and ultra-deep shaft structures.

[0173] The top ring beam 1 is embedded with pre-embedded parts for connection with the main lifting system. Specifically, as follows... Figure 17 As shown, the top ring beam 1 is equipped with a first embedded part 13 for connecting to the main hoisting system. The top ring beam 1 is also equipped with a second embedded part 14 for connecting to the shaft hoisting system. The top ring beam 1 further includes a ground anchor component 15 to ensure a more stable connection between the main hoisting system, the shaft hoisting system, and the top ring beam. The embedded parts can be long bolts, anchor bolts, etc., and their quantity and location can be set according to the shaft size, the shaft hoisting system, and the main hoisting system, and are not limited to these types. Figure 17 The proposed solution is shown.

[0174] Based on the above technical solutions, and addressing the uncertainty and complexity of deep geological conditions, a dynamically controlled excavation and construction system is constructed. This allows the shaft structure to adapt to changes in different geological characteristics in real time, ensuring safety during the shaft sinking process and improving project quality. The adoption of fully automated, unmanned excavation technology minimizes underwater personnel work, significantly reducing construction safety risks. It also minimizes disturbance to the surrounding strata during excavation, ensuring environmental stability and effectively avoiding collapse or deformation accidents common in traditional methods.

[0175] The project utilizes underwater mechanical excavation technology to achieve mechanized and efficient construction in water-rich soft soil strata; optimizes the construction process, enabling one-time shaft completion, reducing workload, shortening construction period, and significantly improving overall construction efficiency; employs a real-time monitoring system and precise correction measures to ensure the efficient and accurate construction of ultra-large and ultra-deep vertical shafts. Considering the limited land resources in the urban core area, low-disturbance and low-noise construction techniques are adopted, along with a waste slurry recycling system, forming a green construction solution. This approach minimizes disruption to the surrounding ecology and residents' lives while promoting the sustainable development of deep underground space development.

[0176] This embodiment also illustrates a waterproofing solution for vertical shafts:

[0177] Based on the above technical solution, during the construction of the vertical shaft, the top of the final standard ring is poured in two stages. The first layer is 0.8m thick (consistent with the thickness of the standard ring segments) and 1.55m high. Before pouring, a water-stop steel plate is circumferentially embedded at the construction joint between the old and new pipe sections to achieve a better water-stopping effect. The cast-in-place concrete structure has a strength grade of C40 and a permeability grade of P12.

[0178] In addition, the joint between the cutting edge ring and the adjacent pipe segment is sealed with an annular steel plate as a waterproofing measure.

[0179] The construction joints between the tunnel segments and the cast-in-place foundation slab concrete are all waterproofed using double-layer water-swellable sealant combined with pre-embedded grouting pipes.

[0180] After construction is completed, before dewatering stops and decoration begins, the process of grouting between the pipe segments and the cast-in-place foundation slab through grouting pipes should preferably use hydrophilic epoxy resin grouting materials. If there is flowing leakage, hydrophobic polyurethane grouting materials should be used.

[0181] Above the base structure is a subbase layer, and on top of the subbase layer is a waterproof membrane. The base surface for laying the waterproof membrane should be cleaned. If there is standing water, it needs to be blocked or temporarily drained. The self-adhesive side of the waterproof membrane should face the cast-in-place concrete structure. Adjacent rolls should overlap and the nail holes should be covered.

[0182] Apply polymer cement waterproof mortar (10mm thick) to the inside of all water collection pools, wells and other structures with water storage functions inside the vertical shaft.

[0183] Furthermore, the well wall is equipped with three waterproof layers: a cement slurry replacement layer on the outside of the well wall, polyurethane caulking material in the gaps between the circumferential and longitudinal joints of the segments, and an EPDM rubber layer on the inner surface of the segments, which has a good waterproof effect.

[0184] Furthermore, the joints between the standard rings utilize double-layered elastic perforated rubber gaskets as a waterproofing measure, capable of withstanding a water pressure of 1.0 MPa for an extended period when the rings are 8 mm wide and 6 mm misaligned. A sand-resistant strip, made of water-swellable rubber, is installed on the water-facing side of the outer gasket.

[0185] At the joint between the connecting ring and the reinforcing ring, double elastic perforated rubber gaskets are installed at the corners inside the boss and the groove, respectively, and sand-blocking strips are installed on the inclined surface of the outer water-facing side.

[0186] Enhanced waterproofing at the anchor bolt holes: Water-swellable adhesive strips are wrapped around the anchor bolts before inserting them into the anchor bolt holes. Upon contact with groundwater, the adhesive strips rapidly expand, forming the first tight seal within the hole. After grouting, the opening is sealed with a sealant possessing good adhesion, elasticity, and water resistance (e.g., polysulfide sealant, polyurethane sealant, silicone sealant, etc.). Finally, cement mortar is used to seal and level the opening.

[0187] The waterproof concrete for the segment structure has a strength grade of C60 and a permeability grade of P12. Leakage testing was also conducted on the segments: under a water pressure of 0.8 MPa, maintaining the pressure for ≥3 hours, the seepage thickness was ≤5 cm.

[0188] Based on the above technical solutions, this embodiment also provides a shaft construction system for constructing any of the shafts described above. For example... Figure 20 As shown, the system includes: a shaft hoisting system, a tunneling equipment 101, a slag removal system, a main unit hoisting system 102, etc.

[0189] The shaft hoisting system is used to lift the shaft and is connected to the cutting edge ring via steel strands. The tunneling equipment is installed on the starting structure of the shaft; the tunneling arm of the equipment excavates downwards into the underlying strata. The muck removal system extends to the excavation face through muck pipes, discharging the excavated muck and slurry through mud circulation. The main hoisting system is located above the top ring beam and connected to the tunneling equipment.

[0190] Based on the above technical solutions, this embodiment also provides a construction method for constructing the vertical shaft provided in any of the above contents, including the following steps:

[0191] Step 1: Construct anti-tension piles downwards around the perimeter of the area to be formed into a well shaft, until the bottom of the anti-tension piles is lower than the bottom of the well shaft.

[0192] Step 2: Excavate the foundation pit in the area where the well shaft is to be formed.

[0193] Step 3: Pour concrete in the foundation pit to form a top ring beam, which is then connected to the tension piles as a whole.

[0194] Step 4: Excavate downwards within the area enclosed by the annular top beam and construct the shaft.

[0195] Step 5: Excavate the strata at the bottom of the well shaft and extend the excavation outwards to near the pull-out piles.

[0196] Step 6: Pour concrete into the lower part of the well to form a bottom sealing structure. The bottom sealing structure is integrated with the anti-uplift pile and the bottom of the well.

[0197] The above technical solution integrates the anti-uplift pile, the top ring beam fixed to the stratum and the shaft into a single structure, which can resist the buoyancy caused by the groundwater around the shaft of a large depth, thereby improving the reliability of the shaft. It is suitable for constructing ultra-large and ultra-deep shafts with a diameter of more than 16 meters and a depth of more than 50 meters, and has a good ability to withstand non-linearly increasing water and soil pressure.

[0198] Furthermore, the steps for constructing the wellbore include:

[0199] Install the cutting edge ring within the space formed by excavating downwards within the area enclosed by the annular top beam;

[0200] An initial ring is installed on top of the cutting edge ring; the initial ring is a ring-shaped structure with an inner side and an outer side.

[0201] A liner is formed on the inner side of the initial ring; the liner is a ring-shaped structure with an inner side and an outer side, and the outer side of the liner contacts and is fixedly connected to the inner side of the initial ring.

[0202] A bottom ring beam is formed on the inner side of the liner; the bottom ring beam is a ring structure that protrudes radially on the inner side of the liner.

[0203] Multiple standard rings are formed sequentially on top of the initial ring.

[0204] The inner wall of the initial ring is equipped with a tunneling equipment mounting base, and the top of the inner lining is lower than the tunneling equipment mounting base; the top of the sealing structure extends to a height higher than the bottom ring beam and is integrated with the launching structure.

[0205] The height of the lining along the vertical shaft direction is greater than the thickness of the lining along the radial direction; the thickness of the bottom ring beam along the radial direction is greater than the thickness of the lining along the radial direction.

[0206] In the process of constructing tension piles, the horizontal distance between the tension pile and the well shaft to be formed is less than or equal to the diameter of the tension pile.

[0207] Based on the above technical solution, the initial ring is provided with pre-embedded steel bars extending radially, which pass through the inner side of the initial ring; an inner lining is formed on the inner side of the initial ring, and a bottom ring beam is formed on the inner side of the inner lining, including: binding a steel cage to the pre-embedded steel bars of the initial ring, and building a casting template outside the steel cage; the shape and size of the steel cage are set to correspond to the inner lining and the bottom ring beam; the inner lining and the bottom ring beam are cast in the casting template.

[0208] The number of initial rings is at least two; the initial rings are installed on the cutting edge ring, specifically by sequentially installing the initial rings on the cutting edge ring. The initial ring consists of multiple initial ring segments spliced ​​together circumferentially; the installation of the initial ring on the cutting edge ring includes: sequentially hoisting each initial ring segment and assembling it into an initial ring.

[0209] One specific scheme is as follows: the number of initial rings is three, namely the first initial ring, the second initial ring, and the third initial ring; installing the initial rings on the cutting edge includes:

[0210] The third type of initial ring segments are hoisted in sequence and installed above the cutting foot ring to form the first initial ring; the inner side of the third type of initial ring segments is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner side of the third type of initial ring segments.

[0211] The third type of initial ring segments are hoisted in sequence and installed above the first initial ring to form the second initial ring; the joints of adjacent third type of initial ring segments in the second initial ring are staggered from the joints of adjacent third type of initial ring segments in the first initial ring.

[0212] The first and second initial ring segments are hoisted and installed above the second initial ring, and spliced ​​together to form the third initial ring. The joints between the first and second initial ring segments are staggered from the joints of adjacent third initial ring segments in the second initial ring. The inner surface of the first initial ring segment has a circumferentially extending recess, and the recess contains embedded reinforcing bars that protrude from the inner surface of the first initial ring segment. The inner surface of the second initial ring segment also has a circumferentially extending recess, and the recess contains embedded reinforcing bars that protrude from the inner surface of the second initial ring segment. A pre-embedded tunneling equipment mounting base is provided on the upper part of the inner surface of the second initial ring segment.

[0213] Furthermore, after installing a predetermined number of standard rings, reinforcing rings are installed between adjacent standard rings. Connecting rings can also be installed between the reinforcing rings and the standard rings. The steps for installing the connecting rings and standard rings include:

[0214] Each connecting ring segment is hoisted and installed above the standard ring, with the joints between adjacent connecting ring segments misaligned with the joints of the standard ring segments. The connecting ring segments are then assembled into a connecting ring.

[0215] The reinforcing ring segments are hoisted and installed above the connecting ring, with the joints between adjacent reinforcing ring segments misaligned with the joints of the connecting ring segments. The reinforcing ring segments are assembled into a reinforcing outer ring. The inner side of the reinforcing outer ring extends inward to form a reinforcing lower ring beam. The reinforcing lower ring beam is equipped with vertical embedded steel bars, the top of which protrudes from the upper surface of the reinforcing lower ring beam.

[0216] A reinforced upper ring beam is formed by casting concrete above the reinforced lower ring beam. The reinforced upper ring beam is fastened to the reinforced lower ring beam by pre-embedded steel bars. The reinforced upper ring beam and the reinforced lower ring beam form the reinforced inner ring in the reinforcing ring.

[0217] The connecting ring segments are hoisted to a position above the reinforcing outer ring, with the joints between adjacent connecting ring segments misaligned with the joints of the reinforcing ring segments.

[0218] Based on the above technical solution, this embodiment provides a specific construction method for large vertical shafts:

[0219] Step 1: Construct tension piles downward around the perimeter of the shaft to be formed. The horizontal distance between the tension piles and the shaft to be formed is less than or equal to the diameter of the tension piles, and the depth of the tension piles is greater than the depth of the shaft to be formed.

[0220] Step 2: Excavate the foundation pit at the location where the shaft is to be formed, up to the design elevation of the bottom of the top ring beam;

[0221] Step 3: Pour a top ring beam into the foundation pit, and connect the top ring beam to the tension piles;

[0222] Step 4: Install the wellbore hoisting system and main unit hoisting system, and connect them to the pre-embedded fixing seats on the top ring beam;

[0223] Step 5: Install the cutting edge ring and connect it to the shaft hoisting system via steel strand; construct the launching structure on top of the cutting edge ring;

[0224] Step 6: Continue excavating the foundation pit until the initial space requirements for the cutting arm of the tunneling equipment are met;

[0225] Step 7: Hoist the assembled and debugged tunneling equipment into the foundation pit, connect it to the pre-embedded tunneling equipment mounting base in the starting structure, and connect it to the main machine lifting system;

[0226] Step 8: Vertically excavate the strata using tunneling equipment. During the excavation process, the shaft sinking and standard ring segment lifting and installation are carried out in a cyclical manner until the designed depth of the vertical shaft is reached.

[0227] Step 9: The tunneling equipment uses a mud circulation mode to remove slag, so as to achieve underwater excavation without dewatering inside the vertical shaft.

[0228] Step 10: Inject thixotropic mud into the shaft wall through the pre-set grouting holes of the standard ring segment;

[0229] Step 11: Excavate the stratum below the cutting edge ring and expand the excavation outward to near the shaft of the pull-out pile;

[0230] Step 12: Seale the bottom of the shaft with underwater concrete, and let the concrete spread outwards to form a whole with the anti-uplift piles;

[0231] Step 13: Pump out the mud from the shaft and clean the bottom. After pumping out the mud, lay a waterproof layer at the bottom of the shaft and pour concrete on top of the waterproof layer to form the base slab.

[0232] Furthermore, during construction, the tunneling equipment uses a mud circulation mode for muck removal, enabling underwater excavation without dewatering within the well.

[0233] Furthermore, during construction, thixotropic mud is injected into the shaft wall through the pre-set grouting holes of the standard ring segments.

[0234] Furthermore, after installing a preset number of standard rings, a reinforcing ring is installed on top of the standard rings; after installing the reinforcing ring, the standard rings are then installed.

[0235] This construction method overcomes the problems of large excavation area and large workload associated with open-cut methods; it also overcomes the high safety risks and severe dust pollution associated with drill-and-blast methods; and it solves the problem of easy shaft deviation and difficulty in correction that traditional caisson methods cannot address. It is particularly suitable for constructing large-diameter, ultra-deep vertical shafts in soft, water-rich soil strata and urban core areas. Furthermore, the combination of anti-uplift piles with top ring beams and bottom sealing structures can resist the buoyancy of groundwater, further making it suitable for the construction of deep vertical shafts. Based on the above solutions, this embodiment provides a specific implementation method using a vertical tunneling machine (VTCM) as the excavation equipment. The VTCM is connected to the launching structure, and the shaft and caisson are lowered via the main machine lifting system and the shaft lifting system. Excavation is carried out without drainage; the shaft is filled with mud during construction, eliminating the need to lower the groundwater level of the caisson and surrounding areas, preventing the collapse of the surrounding soil, and ensuring the safety of the construction process. Shaft construction is divided into a preparation stage, an excavation stage, and a bottom sealing stage. The preparation stage mainly involves site layout and foundation reinforcement. The tunneling phase involves excavation, muck removal, sinking, and support. The bottom sealing phase mainly involves concrete sealing of the bottom and reinforcement of the shaft wall. Precast segment shafts are used for rapid construction.

[0236] In this embodiment, "segment" is a general term for all ring segments. For example, a standard ring is made up of several standard ring segments, and a connecting ring is made up of several connecting ring segments. Connecting ring segments and standard ring segments are collectively referred to as segments.

[0237] I. Preparation Stage; The preparation stage is the process before the formal construction of the caisson-type vertical shaft. It mainly includes the site layout, the entry and storage of the tunneling machine, the construction of the top ring beam and the launching shaft, the assembly of the cutting edge ring, the installation of the shaft hoisting system and the main hoisting system, the installation of the main machine, the connection and installation of ground facilities, and the equipment debugging.

[0238] 1. Site Layout. Before commencing shaft excavation, the site layout must be completed. Considering the assembly and placement of the tunneling machine and the needs of its supporting systems, the site is generally divided into the following functional areas: cutting edge storage area, main unit assembly area, mud treatment area, segment storage area, and equipment and material storage area. The main unit assembly area requires hardened ground with reinforced concrete or paved with steel plates, while the remaining areas are hardened with ordinary concrete.

[0239] 2. Foundation reinforcement. If the shaft is built in a soft soil area, in order to ensure the stability of the soil below the top ring beam during the downward excavation of the shaft boring machine, the soft soil below needs to be reinforced with foundation. The common form is mixing piles, and anti-uplift piles are also driven in.

[0240] 3. Construction of the top ring beam foundation. Before the equipment arrives and is assembled, the foundation pit is excavated and the top ring beam is poured. During construction, embedded parts for the well shaft lifting, main unit lifting, and pipeline extension systems must be pre-embedded, and the positions of the embedded parts must meet the bearing capacity requirements. The pouring of the top ring beam must be integrated with the pouring of the anti-uplift piles.

[0241] 4. Cutting foot ring assembly. The cutting foot ring is assembled inside the launching shaft. Anchors for the shaft hoisting system are installed on the cutting foot ring. The specific installation steps are as follows:

[0242] (1) Lay sleepers or steel plates on a flat and open site, measure the elevation of the upper surface, and ensure that the overall flatness error does not exceed 5mm.

[0243] (2) Number each cutting edge to ensure that the cutting edges with different functions are hoisted to the designed position.

[0244] (3) Weld and fix the inside of the cutting edge ring with I-beams or rectangular steel pipes to prevent deformation during subsequent welding and hoisting.

[0245] (4) Install the earth pressure gauge into the monitoring slot of the cutting foot, and then pull the cable along the inside of the pipe segment to the top of the shaft structure.

[0246] (5) The cutting feet are hoisted one by one by a crane. It is necessary to ensure that the center of the anchor is consistent with the center of the wire groove reserved in the shaft hoisting system, so as to facilitate the subsequent connection with the steel strand.

[0247] (6) Position and assemble the cutting edge.

[0248] (7) After riveting and connecting into a blade foot ring, weld it in place and then inspect it for defects.

[0249] (8) After the flaw detection requirements are met, the cutting foot ring is hoisted into the well ring as a whole.

[0250] (9) Backfill the cavity of the cutting edge with concrete.

[0251] 5. Install the shaft hoisting system. The shaft hoisting system consists of a hydraulic continuous hoisting system, a shaft hoisting anchor system, and auxiliary mechanisms. It is mainly used for hoisting the supporting segments and controlling the verticality and flatness of the shaft. The specific installation steps are as follows:

[0252] (1) Fix the lifting top, hydraulic pump station and control cabinet according to the design requirements, and complete the preparation work of the hydraulic pump station.

[0253] (2) Assemble the wellbore hoisting system components such as the guide frame and hoisting top.

[0254] (3) Based on the location of the embedded parts of the top ring beam, the well shaft lifting system is hoisted one by one by a crane and the bolts are tightened.

[0255] (4) Connect the hydraulic and electrical pipelines according to the drawings to ensure system integration.

[0256] (5) Check the proximity switch, pressure sensor, displacement sensor and other components and adjust them to normal working condition.

[0257] (6) Insert the steel strands into the well hoisting system and make initial connections.

[0258] (7) Make the piston of the lifting top return to the bottom and loosen the clamping bolts of the upper and lower clamping tops and the component clamping tops.

[0259] (8) Grind the straight end of the inserted steel strand into a pyramid shape using a grinding wheel to make it easier to insert.

[0260] (9) After the system is powered on, lower the steel strand to the height of the cutting foot ring and connect it to the cutting foot ring through the anchor.

[0261] (10) After the cable is threaded, the tension of the steel strands is adjusted uniformly on the ground to ensure that each cable is evenly tensioned.

[0262] (11) Perform pre-tightening operations and trial lifting to verify system stability.

[0263] 6. Construction of the initial structure. The initial ring segments are connected above the cutting edge ring and equipped with mounting bases for the tunneling equipment, used to connect the shaft excavation equipment. The specific installation steps are as follows:

[0264] (1) The cutting edge ring is kept suspended under the lifting action of the wellbore hoisting system.

[0265] (2) Use a total station to measure the upper surface of the cutting edge ring and level it in conjunction with the shaft hoisting system to facilitate subsequent segment installation.

[0266] (3) Use a crane to assemble the initial three rings on the cutting edge ring and fix them into a ring with bolts.

[0267] The steps described above, including the installation of the starting structure on the cutting edge ring, include: first, installing an initial ring on the cutting edge, with pre-embedded reinforcing bars inside the initial ring; then, casting concrete on the inner side of the initial ring to form an inner lining and a bottom ring beam; the inner lining is located between the bottom ring beam and the initial ring.

[0268] The initial ring consists of at least two segments, one for installing the tunneling equipment and the other for connecting the bottom ring beam, installed sequentially along the vertical direction. The initial ring comprises multiple initial ring segments. Installing the initial ring on the cutting edge includes: hoisting the initial ring segments one by one into the shaft and installing them on the cutting edge ring, and assembling them into one initial ring; then repeating the hoisting and assembly of the next initial ring and installing it on the previous initial ring.

[0269] Based on the above scheme, there are three initial rings: a first initial ring, a second initial ring, and a third initial ring. Installing the initial rings on the cutting edge includes the following steps:

[0270] (1) Several third-type initial ring segments are hoisted into the well shaft and installed on the cutting foot ring to form the first initial ring; the inner side of the third-type initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner side of the third-type initial ring segment.

[0271] (2) Several third-type initial ring segments are hoisted into the wellbore and installed above the first initial ring to form the second initial ring;

[0272] (3) Several first-type initial ring segments and second-type initial ring segments are hoisted one by one onto the second initial ring and spliced ​​together to form a third initial ring; the inner side of the first-type initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner side of the first-type initial ring segment; the inner side of the second-type initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner side of the second-type initial ring segment; the upper part of the inner side of the second-type initial ring segment is provided with a pre-embedded tunneling equipment mounting seat.

[0273] 7. Lining and Bottom Ring Beam Construction. After the cutting edge ring and initial ring are installed, the lining and bottom ring beam are cast in place to enhance the overall rigidity and integrity of the bottom of the shaft. This will enable the shaft to jointly bear the lifting force of the shaft, the water pressure inside and outside the shaft, the working support force of the tunneling machine during construction, and transmit the structural buoyancy during operation.

[0274] 8. Install muck discharge pipes. As the diameter of the shaft increases, the amount of excavated soil gradually increases. To ensure tunneling efficiency, it is necessary to promptly pump out the muck. In addition to the tunneling machine's built-in mud circulation system, a certain number of auxiliary muck discharge pipes should be laid and fixed to the bottom ring beam to ensure timely discharge of muck during tunneling and to prevent the pipes from being disturbed by the main machine's cutting arm. Before the caisson-type shaft tunneling machine begins construction, the concrete cushion layer inside the launching shaft should be broken, and the launching pit should be excavated using an excavator. The height of the bottom of the launching shaft from the ground should be sufficient to provide space for the installation of the main machine.

[0275] 9. Install the tunneling equipment, i.e., the tunneling machine main unit. The tunneling machine main unit mainly consists of the excavation system, the boom rotation drive system, and the main unit support system. After being assembled on the ground, it is hoisted into the shaft and connected to the launching structure. The specific steps are as follows:

[0276] (1) The main unit is assembled on the ground and the tunneling equipment is installed.

[0277] (2) The assembled main unit is hoisted into the starting shaft and connected to the tunneling equipment mounting base. When hoisting the main unit, the direction of the main unit support arm should be adjusted so that the main unit is assembled in a position that facilitates pipeline connection; the tunneling arm needs to be in a downward vertical state to prevent interference with the bottom ring beam structure; during hoisting, attention should be paid to the uniform force on each hoisting point to ensure stable hoisting.

[0278] 10. Install supporting equipment. After the main unit is installed, install the main unit lifting system and pipeline extension system in the ground according to the pre-embedded positions of the pre-embedded parts, ensuring accurate installation positions; and arrange other supporting equipment such as mud-water separation station, main control room, and hydraulic pump station on the ground; and connect the electrical system cables.

[0279] 11. Equipment commissioning. This is divided into pre-commissioning preparation and commissioning.

[0280] (1) Preparations before commissioning mainly include: checking the hydraulic pipeline and joint tightness; confirming that the main unit support pin cylinder is in place; checking the electrical system cable connection; verifying the status of the hydraulic system gate valve; checking the cooling water, hydraulic oil, and gear oil levels; cleaning and replenishing the oil.

[0281] (2) Equipment commissioning mainly involves powering on the equipment in the order of high voltage, power, and control, checking the voltage and the status of the high voltage cabinet; checking the pipelines and valve groups, and then starting the pump station in sequence; verifying whether the interlocking and safety functions meet the requirements; and then commissioning the tunneling arm, cutterhead, slewing device, main engine recovery, and shaft sinking in sequence.

[0282] II. Tunneling Stage; After completing the site preparation and equipment assembly procedures before tunneling, the shaft excavation begins using the non-drainage method. The specific construction method is as follows:

[0283] 1. Mud Circulation. To meet environmental protection requirements, mud circulation is used to "recycle" waste mud. Before shaft excavation, mud preparation is necessary. Through a process logic of graded treatment, precise control, and dynamic adaptation, the specific gravity of the underwater construction mud is ensured to be between 1.03-1.1 g / cm³, and the performance of the thixotropic mud meets the construction requirements. The specific adjustment steps are as follows:

[0284] (1) Screening to remove solid impurities and purify the mud matrix;

[0285] Excavated soil undergoes three-stage screening to obtain primary recycled mud: a "staged cyclone separation" method replaces the traditional screening + centrifugation process, utilizing the centrifugal force gradient of the cyclone separator to achieve precise classification and removal of impurities. The first-stage cyclone focuses on large-diameter obstructive impurities (affecting pipeline flow), the second-stage cyclone targets medium-diameter particles (interfering with mud viscosity), and the third-stage cyclone removes fine-diameter particles (affecting lubrication layer formation), progressively improving mud purity and laying the foundation for subsequent composition adjustments.

[0286] Impurity monitoring: The particle size distribution of the primary recycled sludge is monitored in real time by an online particle size analyzer to ensure that the content of particles with a diameter greater than 0.075mm is ≤3%. Otherwise, the sludge is returned to the centrifuge for reprocessing until the purification requirements are met.

[0287] (2) Adjust the mud composition, target and regulate performance, and adapt to two types of mud;

[0288] Composition adjustment involves precisely regulating the physical and mechanical properties of circulating mud and thixotropic mud by adding modifiers, based on their different functional requirements. This is achieved through two main control pathways:

[0289] Circulating mud: This is the mud inside the wellbore during underwater construction, formed by a mixture of groundwater and excavated soil. After being pumped out of the wellbore and subjected to three-stage screening, it is adjusted to meet the specific gravity requirements before being reinjected into the wellbore. It needs to be adapted to carry the excavated soil, possessing sufficient viscosity to suspend the excavated soil and sufficient fluidity to reduce pipeline resistance. Specific adjustment methods are as follows:

[0290] ① Adding bentonite to the primary recycled mud increases the colloid content of the mud (≥95%) and enhances the suspension capacity of the slag and soil.

[0291] ② Add carboxymethyl cellulose as a thickener to adjust the slurry viscosity to 20-25s, ensuring that the slag does not settle during transportation;

[0292] ③ Add clean water or concentrated mud to control the mud's specific gravity, ensuring both slag-carrying capacity and avoiding excessive specific gravity that would increase circulation energy consumption.

[0293] Thixotropic mud: It needs to be suitable for both lubrication and water retention, forming a stable lubricating layer between the wellbore outer wall and the formation to reduce sinking resistance. Simultaneously, it must possess good water retention to prevent rapid water loss and lubrication layer failure. Specific operating methods are as follows:

[0294] ① Add an appropriate amount of high-purity bentonite to the primary recycled mud to increase the static yield value of the mud and ensure that the lubrication layer is not squeezed out under soil pressure.

[0295] ② Add an appropriate amount of water-retaining agent, such as polyacrylamide, to prolong the evaporation time of the mud moisture and ensure the effective duration of the lubrication layer;

[0296] ③ If necessary, add an appropriate amount of sealing agent (such as sawdust) to enhance the seepage resistance of the mud when encountering high-porosity formations. At this time, it is necessary to increase the mud viscosity and static yield value to match the formation characteristics.

[0297] (3) Stir and homogenize to ensure uniform performance and avoid stratification and segregation;

[0298] The modified mud needs to be homogenized by stirring to ensure that the modifier and primary recycled mud are fully mixed and to avoid performance fluctuations. A twin-shaft screw mixer is used for stirring to ensure that all components of the mud are mixed evenly and without clumping or sedimentation. During the stirring process, the mud properties are monitored in real time by an online viscometer and hydrometer. Qualified circulating mud is temporarily stored in a circulating mud tank, and thixotropic mud is temporarily stored in a thixotropic mud tank. A low-speed mixer is installed in the tank for continuous stirring to prevent stratification and segregation during settling.

[0299] (4) Quality verification to ensure the effectiveness of reuse;

[0300] The treated mud must undergo rigorous testing to meet specific reference parameters for reuse before it can be put into use.

[0301] The circulating mud must meet the following requirements: suitable viscosity, specific gravity and sand content, and the soil settling rate must meet the requirements after trial transport test;

[0302] Thixotropic mud must meet the following requirements: suitable viscosity, static yield value and filtration loss, and frictional resistance reduction rate.

[0303] 2. Equipment load test run. Analyze and adjust construction parameters such as the depth of the cutting edge and the construction time of a single ring to determine tunneling parameters, such as excavation rate, mode, and muck removal efficiency.

[0304] 3. Formal excavation. A vertical shaft tunneling machine is used to excavate inside the caisson. The excavated soil is discharged through a mud circulation mode and treated. The treated mud is circulated back to the excavation chamber through the slurry inlet pipeline, realizing the green recycling of mud.

[0305] (1) Excavation and support mode. Different excavation methods are used depending on the different shaft excavation equipment. The depth of a single excavation is usually 100-200mm. At the same time, the excavation mode is switched according to the different geological characteristics: For geology with good self-stabilizing ability, the alternating excavation mode is adopted. After the cutting arm of the tunnel boring machine completes one ring segment stroke (2m), the shaft hoisting system automatically sinks the shaft to the depth of that stroke. Excavation and support are carried out alternately (alternating excavation mode); For soft geology, the synchronous excavation mode is adopted. After the cutting arm of the tunnel boring machine completes one conventional cycle trajectory excavation (0.15m deep), the shaft hoisting system automatically sinks the shaft to a depth of 0.15m. Excavation and support are carried out synchronously; For extremely unstable strata, the advanced support mode is adopted. For example, in soft soil strata, in order to prevent ground subsidence, the cutting edge ring is first slid below the working face by the propulsion cylinder so that the cutting edge is inserted into the original soil. After the tunnel boring machine's cutting arm completes one cycle trajectory excavation in the steel cutting edge, the shaft hoisting system automatically sinks the shaft.

[0306] (2) Excavation method. The excavation system adopts a differentiated excavation method for different strata: for soft soil strata, the cutting device adopts excavation parameters of high speed and small feed to reduce strata disturbance; for hard interlayers or dense strata, the excavation parameters of low speed and large feed are adopted to improve cutting efficiency, and the cutting trajectory is controlled by the drive system to advance in a circular zone during the excavation process.

[0307] (3) Excavation and muck removal. The caisson-type vertical shaft excavator uses a mud circulation mode to pump out the muck. The appropriate mud level is determined based on the surrounding groundwater level. Generally, the hydraulic pressure inside the shaft is 1m higher than the groundwater level. At the same time, the amount of muck pumped in the auxiliary muck removal pipeline is dynamically adjusted according to the amount of muck to meet the requirements for muck discharge and maintain the density of the mud inside the shaft.

[0308] 4. Thixotropic grouting behind the tunnel lining. Based on geological conditions, grouting holes are pre-set on the tunnel lining segments, and thixotropic grout is injected between the tunnel lining segments and the external soil to reduce settling resistance and provide grout wall protection.

[0309] 5. Shaft sinking. After excavation, the caisson can be gradually sunk. When the sinking reaches the height of one segment, the vertical shaft segments hoisted from the top are used to complete the support, and this process is repeated in sequence.

[0310] Theoretically, the controlled-sinking method can construct shafts of any depth. However, in practice, as the shaft depth increases, the frictional resistance of the shaft wall rises sharply, making sinking difficult. Furthermore, as the depth of the caisson gradually increases, its self-weight also increases, and the maximum suspension force required in each excavation cycle gradually increases as well. When the suspension force cannot meet the increased demands of the shaft's self-weight, the theoretical maximum depth for the controlled-sinking method is reached. Therefore, the traditional controlled-sinking method is difficult to implement for constructing ultra-deep shafts. Thus, to construct ultra-deep shafts, a composite sinking process is necessary.

[0311] Furthermore, stress-strain monitoring can be employed, installed on the suspension steel strands or hydraulic cylinders of the wellbore hoisting system, to monitor tension in real time and ensure safe descent. Geometric attitude monitoring, such as inclinometers, tiltmeters, and measuring robots, can be used to monitor the verticality, planar position, and elevation of the wellbore in real time to prevent deviation. Earth pressure monitoring can be used, for example, by installing earth pressure cells in an array at the well wall and cutting edge to monitor reaction forces.

[0312] During the caisson's sinking process, it is subjected to the following forces: its own weight (downward vertically, including the caisson walls, machinery, etc.), upward buoyancy (during non-drainage excavation), frictional resistance behind the walls (approximately upward vertically) in the opposite direction to the caisson's movement, and cutting edge resistance (approximately upward vertically). To reduce frictional resistance, grouting behind the walls can be used to ensure the smooth sinking of the caisson.

[0313] Assuming the shaft sinks at a constant speed and is in a state of force equilibrium:

[0314]

[0315] Self-weight, which can be calculated from the number of rings and the weight of the equipment construction;

[0316] The lifting (suspension) force is measured through each wellbore lifting system and must be less than the lifting force limit value.

[0317] Sinking force is obtained through various hydraulic jacking systems;

[0318] : Well wall friction resistance, well wall surface friction monitoring points are set up in the precast segment structure, one monitoring layer is set up for every 4 rings of segments, and 5 segments are set up in each layer to monitor the well wall surface friction.

[0319] Buoyancy is calculated based on the sinking depth, liquid level, and mud mix ratio.

[0320] Resistance at the cutting edge is monitored by setting up inclined pressure monitoring points below the side of the steel cutting edge.

[0321] In areas with deep soft soil, the possibility of sudden sinking of ultra-large caissons is greater when the burial depth is shallow than when the burial depth is deep. In particular, the process of segment assembly can easily cause the center of gravity to deviate, resulting in uneven sinking.

[0322] When the caisson is shallowly buried, and the suspension force is sufficient to meet the self-weight requirements, the fully controlled lifting and sinking method is used for caisson construction, with zero resistance at the cutting edge. The steps are as follows: the tunnel boring machine excavates, the suspension equipment lowers the shaft, and after circulating to the height of one ring of segments, the segments are assembled, and the construction of the next ring begins.

[0323] In the construction of deep shafts, as the shaft sinks deeper, its weight gradually increases, potentially leading to insufficient lifting capacity of the suspension system to fully support the shaft's weight. Furthermore, the process of removing mud and soil during the sinking of deeper shafts can cause soil disturbance, weakening the vertical soil resistance and increasing the risk of sudden sinking. Additionally, the shaft wall may experience additional lateral pressure due to soil loosening, leading to structural deformation or damage. To safely control the sinking process, a combination of controlled sinking and self-weight sinking methods can be used, fully utilizing the support reaction force at the cutting edge (i.e., the soil's support reaction force on the cutting edge during sinking, obtained from the resistance measured at the cutting edge) to balance part of the shaft's weight. The specific steps are as follows:

[0324] (1) A certain length of steel strand (10-15cm) of the controllable release lifting system (corresponding to the single-layer excavation volume of the tunneling machine) is used to sink the caisson under its own weight, and the cutting edge cuts into the soil. The release length can be dynamically adjusted with reference to the soil pressure value at the cutting edge, and the release amount should be minimized in soft soil layers; it can be appropriately increased in hard rock. For a given safe cutting edge soil pressure threshold... If monitoring the earth pressure at the cutting edge Greater than If the monitored values ​​do not fluctuate significantly, then continue releasing the steel strands at the current rate. A sharp drop or close to If the release is interrupted, or the emergency brake is activated, the tunneling machine can pause excavation at that location and take adjustment measures (such as increasing the frictional resistance behind the shaft wall).

[0325] (2) Repeat the above steps until the caisson can no longer sink on its own (at this point, the sum of the reaction force at the cutting edge and the frictional resistance of the well wall is close to the weight of the well) or the sinking amount reaches the width of 1 ring segment.

[0326] (3) Use a shaft excavator to excavate the soil below the cutting edge to reduce the support reaction force and make the caisson have the conditions to continue sinking.

[0327] When excavating with a tunnel boring machine, soil should be evenly removed along the bottom cross-section of the shaft, prioritizing the excavation of the central area. The soil ridges on the inner side of the cutting edge should be preserved as temporary support, and finally the soil ridges should be symmetrically removed. This is to prevent sudden settlement and tilting.

[0328] (4) Assemble one ring of segments at the top of the well to increase the length of the well. Before assembly, it should be confirmed that the well is in a completely stable state.

[0329] (5) Repeat the above process of “release → sinking by its own weight → excavation → assembly” until the caisson reaches the designed depth.

[0330] In the construction of ultra-deep vertical shafts, the suspension force provided by the shaft hoisting system is completely insufficient to meet the self-weight requirements of the shaft, necessitating the use of the reaction force at the cutting edge to ensure the safety of the shaft. In this case, a combined process of suspension hoisting, self-weight sinking, and pressure sinking is employed, with the specific steps as follows:

[0331] (1) The wellbore is lifted by the lifting system, and the lifting force, the reaction force at the cutting edge, the frictional resistance of the well wall, the buoyancy of the wellbore and its own weight reach a stable equilibrium.

[0332] (2) The tunneling machine removes a very small amount of soil in the central area of ​​the shaft bottom, strictly preserving the soil embankment below the cutting edge, and slightly reducing the support reaction force at the cutting edge. The hoisting system also starts to release the steel strands in a controlled and slow manner at the same time.

[0333] (3) During this linkage process, monitor the changes in the reaction force of the cutting foot support and the lifting force in real time to ensure that the sinking is stable and controllable. At the same time, the frictional resistance behind the wall can be appropriately increased to reduce the risk of sudden sinking.

[0334] (4) Repeat steps 1-3 until the height of one ring is reached, and then assemble the next ring segment.

[0335] (5) If the small amount of excavation and release of the steel strands in step 2 fail to sink the well casing, the jacking system should be started to apply downward pressure while maintaining suspension. However, care should be taken to prevent the well casing from sinking instead of being compressed between the casings. In this case, the sinking must be stopped immediately. At the same time, the back wall grouting can be optimized to reduce frictional resistance; check whether the soil below the cutting edge has been effectively excavated; assess the geological conditions and consider whether to switch the excavation mode.

[0336] The shaft is lowered according to the excavation depth, and standard rings, reinforcing rings, and connecting rings are installed at the top of the shaft. Each segment is hoisted into place, and the rings are staggered and connected by bolts. Segments within the same ring are also connected by bolts.

[0337] The reinforcing ring consists of precast sections and cast-in-place concrete sections. The precast sections are hoisted and aligned with the upper part of the lower connecting ring, then assembled together and secured with bolts, with each ring stacked alternately. The reinforcing ring segments are connected by bolts. The precast sections are formed into a single unit by binding reinforcing steel bars and pouring the upper concrete. The specific construction process is as follows:

[0338] (1) Hoisting the reinforced ring segments.

[0339] (2) The reinforcing ring segments are bolted to the connecting rings, and the reinforcing ring segments are transversely connected.

[0340] (3) Tie the reinforcing bars at the lower ring beam so that the reinforcing bars wrap around the lower ring beam.

[0341] (4) Support the formwork vertically upward along the reinforced lower ring beam.

[0342] (5) Pour early-strength concrete.

[0343] (6) Hoist the connecting ring and connect it to the reinforcing ring.

[0344] Based on the specific structural form of the reinforcing ring described above, installing the reinforcing ring on top of the standard ring involves the following steps:

[0345] (1) The prefabricated connecting ring segments are hoisted one by one above the standard ring segments and stacked in a staggered manner with the standard ring segments to form a connecting ring;

[0346] (2) The prefabricated reinforcing ring segments are hoisted and installed one by one above the connecting ring, and stacked in a staggered manner with the connecting ring segments to form a reinforcing outer ring; the inner side of the reinforcing outer ring extends inward to form a reinforcing lower ring beam; the reinforcing lower ring beam is provided with vertical embedded steel bars, and the top of the embedded steel bars passes through the upper surface of the reinforcing lower ring beam.

[0347] (3) A reinforced upper ring beam is cast in place above the reinforced lower ring beam. The reinforced upper ring beam is fastened to the reinforced lower ring beam by pre-embedded steel bars. The reinforced upper ring beam and the reinforced lower ring beam form the reinforced inner ring in the reinforced ring.

[0348] (4) Hoist and install the connecting ring segment above the reinforcing ring segment, and stack the connecting ring segment and the reinforcing ring segment in a staggered manner.

[0349] During the tunneling process, the construction system uses surveying technology, computer technology, and mechatronics to guide the construction of the caisson-type vertical shaft tunneling machine. The three-dimensional measurement system mainly includes a dual-axis tilt sensor, an inclinometer, and a total station.

[0350] Specifically, a dual-axis tilt sensor is installed on the tunneling machine to monitor its attitude and obtain the shaft tilt angle to determine if the shaft is tilting. An inclinometer is installed on the shaft to monitor its horizontal displacement. At the same time, a total station is used to measure the height of various points on the upper part of the shaft, the distance between the outer arc surface of the shaft and the ground ring beam structure, and the verticality of the upper tunnel segments. The data obtained from the tilt sensor, inclinometer, and total station are used to analyze the tunneling attitude and shaft attitude. When the equipment attitude deviates from the set value, the lifting force of the shaft hoisting system is adjusted, and directional excavation is carried out to ensure that the vertical accuracy of the shaft is within the specified range.

[0351] When the wellbore tilts, a lifting force is applied to the tilted side, and a downward pressure is applied to the deviated side, gradually leveling the wellbore and restoring it to its vertical position. Specifically:

[0352] 6. Shaft Correction. During the sinking process, the shaft's attitude is monitored through tunneling guidance and ground surveying. If the shaft tilts during sinking, correction can be achieved by combining the shaft hoisting system, the jack-assisted sinking system, and the tunneling machine's over-excavation. The specific implementation method is as follows:

[0353] Lifting force is provided on the inclined side, while jacks are used to press down on the corresponding side, gradually achieving leveling and correction during the overall sinking process. Furthermore, during excavation, the circumferential over-excavation on the offset side can be reduced, or even changed from over-excavation to under-excavation, increasing the over-excavation on the opposite side and using the lateral pressure of the soil to push the shaft towards the center. The shaft's posture can also be adjusted by grouting the wall thickness. After the shaft sinks to the design elevation, the grouting pressure at different locations can be adjusted, using the reaction force of the grouting pressure to correct the shaft's deviation.

[0354] If the shaft deviates horizontally, several pads can be placed along the circumference between the ring beam and the shaft wall. The posture of the shaft can be judged by the degree of compression between the pads and the shaft wall, and the degree of tilt of the shaft can also be limited.

[0355] In addition, wellbore deviation can be corrected by controlling the amount of pre-drilling. This method assumes that:

[0356] ① Applicable to horizontal curve correction during vertical shaft excavation;

[0357] ② Assume the strata are not compressible;

[0358] ③ Overall, the correction is performed at a small angle (the correction angle θ is relatively small). );

[0359] During the correction process, the well casing is first suspended using the well casing hoisting system, and then the soil below the well casing is over-excavated. The over-excavation depth is consistent with the height of the main unit. Furthermore, at the well casing deviation measurement, the soil is sequentially over-excavated downwards, with the lowest over-excavation reaching a horizontal distance Hθ. The overall over-excavation is controlled by two mechanisms as follows: Figure 18 and Figure 19 As shown.

[0360] In the diagram, θ represents the verticality deviation angle of the tunneling machine, H represents the height of the tunneling machine, and R represents the excavation radius. The shape after over-excavation can be approximated as a circle with a diameter of 2R + Hθ.

[0361] Over-excavation formula: .

[0362] By controlling the over-excavation in advance to ensure that the new sinking direction returns to vertical, the upper soil is simultaneously corrected to vertical by using a suspension and compaction system.

[0363] III. Bottom Sealing Stage; The bottom sealing stage generally consists of the following steps:

[0364] 1. Bottom Reinforcement. After the shaft is excavated and sunk to the designed depth, the soil outside the shaft is excavated using the extension and retraction arm of the tunnel boring machine, approaching the tension pile. At the same time, concrete pipes are laid, which need to be inserted into the soil outside the shaft and as close as possible to the tension pile. Anti-segregation concrete is injected into the soil through the pipes, and the concrete diffuses around the tension pile to form a unified structure.

[0365] 2. Tunneling machine recovery. After the main unit has fully circulated and discharged the rock debris from the mud chamber, the connection between the support arm and the tunneling equipment mounting base is loosened. The main unit is then simultaneously lifted to the wellhead using the main unit lifting system and pipeline extension system. Finally, a crawler crane is used to move the main unit to the ground tooling.

[0366] 3. Backfilling with mud. Pure cement grout is used to replace the mud behind the shaft wall from bottom to top. Grouting is stopped once cement grout overflows from the wellhead behind the shaft wall. To ensure the compactness of the grout, preliminary backfilling and replacement and secondary grouting can be carried out.

[0367] 4. Slurry Pumping. Install a slurry pump in the shaft and suspend the pump body underwater. Pump slurry according to the amount of concrete poured in, preventing the slurry level in the shaft from rising and overflowing. Clean water is discharged directly to the on-site sedimentation tank, while slurry is discharged into the filter press storage tank. After the bottom sealing is completed, wait for the concrete to reach the initial setting strength requirement, and then drain the remaining slurry from the shaft. Shaft construction is complete.

[0368] 5. Drive in anchor bolts. Through the anchor bolt holes pre-drilled on the reinforcing ring, drive the anchor bolts through the holes from the inside of the well casing into the bottom soil, and then reinforce the strata outside the well casing by grouting through the grouting holes inside the anchor bolts.

[0369] 6. Foundation Slab Construction. The mud in the vertical shaft is pumped out and the bottom is cleaned. After the mud is pumped out, a waterproof layer is laid at the bottom of the vertical shaft, and concrete is poured on top of the waterproof layer to form the foundation slab.

[0370] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0371] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0372] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0373] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0374] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A large shaft, characterized in that include: The wellbore consists of multiple ring segments spliced ​​together; from bottom to top, the cutting edge ring, the starting structure, and the standard ring are arranged sequentially. Multiple standard rings are sequentially arranged along the depth direction of the shaft; The top ring beam is ring-shaped and is set on the outer side of the top of the well shaft. The top ring beam includes a main body and an anti-pull-out section. The anti-pull-out section is located outside the main body of the top ring, extends radially outward to the top of the anti-pull-out pile, and is connected to the anti-pull-out pile. The top ring beam is embedded with a pre-embedded fixing seat for connecting with the main hoisting system and the well shaft hoisting system. The tension piles are installed below the top ring beam and on the outside of the shaft along the depth direction of the shaft. The bottom end of the tension pile is lower than the bottom end of the shaft and is cast into one piece with the bottom end of the shaft. The top end of the tension pile is fixedly connected to the top ring beam. The horizontal distance between the tension pile and the outer side of the shaft is less than or equal to the diameter of the tension pile. The lower part of the well shaft is provided with a bottom sealing structure; the bottom end of the bottom sealing structure is lower than the bottom end of the well shaft. The bottom sealing structure is formed by excavating into the strata below the well shaft and expanding outward to near the anti-uplift pile, and then injecting concrete into the excavated area; the bottom sealing structure is formed by pouring concrete and is integrated with the bottom of the well shaft; the bottom sealing structure extends radially outward and is integrated with the anti-uplift pile. The well shaft also includes a reinforcing ring, which consists of an outer reinforcing ring and an inner reinforcing ring. The outer reinforcing ring is located between two standard rings, and the inner reinforcing ring protrudes radially from the inner side of the outer reinforcing ring. The inner side of the outer reinforcing ring extends inward to form a lower reinforcing ring beam. The outer reinforcing ring and the lower reinforcing ring beam are precast components integrally formed. The lower reinforcing ring beam is equipped with embedded reinforcing bars, the top of which protrudes from the upper surface of the lower reinforcing ring beam. A reinforced upper ring beam is formed by casting concrete above the lower reinforcing ring beam, and the upper reinforcing ring beam is fastened to the lower reinforcing ring beam by embedded reinforcing bars. The upper and lower reinforcing ring beams form the inner reinforcing ring within the reinforcing ring.

2. Large shaft according to claim 1, characterized in that The initial structure includes: The initial ring is a ring-shaped structure with an inner and outer surface; the initial ring is located above the cutting edge ring. The liner is a ring-shaped structure with an inner side and an outer side. The outer side of the liner contacts and is fixedly connected to the inner side of the initial ring. The bottom ring beam is a ring-shaped structure that protrudes radially onto the inner side of the lining.

3. The large vertical shaft according to claim 2, characterized in that, The inner wall of the initial ring is provided with a tunneling equipment mounting seat for installing tunneling equipment, and the top of the liner is lower than the tunneling equipment mounting seat; the top of the bottom sealing structure extends above the bottom ring beam to be integrated with the launching structure.

4. The large vertical shaft according to claim 2, characterized in that, The height of the lining along the vertical shaft direction is greater than the thickness of the lining along the radial direction.

5. The large vertical shaft according to claim 4, characterized in that, The radial thickness of the bottom ring beam is greater than the radial thickness of the inner lining.

6. The large vertical shaft according to claim 1, characterized in that, The top surface of the tensile strength section is flush with the main body of the top ring, while the bottom surface of the tensile strength section is higher than the bottom surface of the main body of the top ring.

7. The large vertical shaft according to claim 6, characterized in that, The tension piles are divided into two groups, with each group's tension piles arranged in a ring. One group of tension piles is located outside the other group's tension piles; each tension pile in both groups is fixedly connected to the top ring beam.

8. The large vertical shaft according to claim 7, characterized in that, A set of tension piles located on the inner side is set below the inner end of the tension section of the top ring beam, and a set of tension piles located on the outer side is set below the outer end of the tension section of the top ring beam.

9. The large vertical shaft according to claim 2, characterized in that, The initial ring is provided with pre-embedded steel bars extending radially, which protrude from the inner side of the initial ring; the inner lining is formed on the inner side of the initial ring by cast-in-place concrete; the bottom ring beam is formed on the inner side of the inner lining by cast-in-place concrete.

10. The large vertical shaft according to claim 9, characterized in that, The bottom ring beam includes: the bottom ring beam body and the bottom ring beam connecting part. The bottom ring beam body is ring-shaped and has a preset distance between it and the inner lining. The bottom ring beam connection extends radially and connects the bottom ring beam body and the inner lining; multiple bottom ring beam connections are spaced apart circumferentially.

11. The large vertical shaft according to claim 2, characterized in that, The initial number of rings is at least two, arranged sequentially along the depth direction of the shaft.

12. The large vertical shaft according to claim 11, characterized in that, The initial ring includes three types of initial ring segments: the first type, the second type, and the third type. Each type of initial ring segment is spliced ​​together accordingly. The inner surface of the first type of initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner surface of the first type of initial ring segment. The inner side of the second type of initial ring segment is provided with a recess extending in the circumferential direction, and the recess is provided with embedded steel bars, which pass through the inner side of the second type of initial ring segment; the upper part of the inner side of the second type of initial ring segment is provided with a tunneling equipment mounting seat for installing tunneling equipment. The inner surface of the third type of initial ring segment is provided with a circumferentially extending recess, and the recess is provided with embedded steel bars, which pass through the inner surface of the third type of initial ring segment.

13. The large vertical shaft according to claim 12, characterized in that, There are three initial rings, arranged sequentially along the depth of the shaft; the initial ring at the top layer consists of alternating splicing of first-type and second-type initial ring segments; The initial ring located in the intermediate layer is composed of third-type initial ring segments spliced ​​together circumferentially. The initial ring at the bottom layer consists of third-type initial ring segments spliced ​​together circumferentially; In the initial ring segment, the lower recess can be aligned and spliced ​​with the upper recess of the third type of initial ring segment.

14. A construction method for constructing a large vertical shaft according to any one of claims 1-13, characterized in that, include: Construct anti-tension piles downwards around the area where the well shaft is to be formed, until the bottom of the anti-tension piles is lower than the bottom of the well shaft. Open excavation of the foundation pit in the area where the well shaft is to be formed; Concrete is poured into the foundation pit to form a top ring beam, which is connected to the anti-uplift piles as one unit; a pre-embedded fixing seat for connecting with the main hoisting system and the shaft hoisting system is embedded in the top ring beam; Excavate downwards within the area enclosed by the annular top beam and construct the shaft; Excavate the strata at the bottom of the well shaft and extend the excavation outwards to near the pull-out piles; Concrete is poured into the lower part of the well to form a bottom sealing structure, which is then integrated with the anti-uplift piles and the bottom of the well.

15. The construction method for a large vertical shaft according to claim 14, characterized in that, The steps for constructing a well shaft include: Install the cutting edge ring within the space formed by excavating downwards within the area enclosed by the annular top beam; An initial ring is installed on top of the cutting edge ring; the initial ring is a ring-shaped structure with an inner side and an outer side. A liner is formed on the inner side of the initial ring; the liner is a ring-shaped structure with an inner side and an outer side, and the outer side of the liner contacts and is fixedly connected to the inner side of the initial ring. A bottom ring beam is formed on the inner side of the liner; the bottom ring beam is a ring structure that protrudes radially on the inner side of the liner. Multiple standard rings are formed sequentially on top of the initial ring.

16. The construction method for a large vertical shaft according to claim 15, characterized in that, The initial ring contains pre-embedded reinforcing bars extending radially, which protrude from the inner side of the initial ring; an inner lining is formed on the inner side of the initial ring, and a bottom ring beam is formed on the inner side of the inner lining, including: A reinforcing cage is tied to the pre-embedded reinforcing bars of the initial ring, and a casting formwork is erected outside the reinforcing cage; the shape and size of the reinforcing cage are set in accordance with the inner lining and the bottom ring beam. The inner lining and bottom ring beam are formed by casting within the casting template.

17. The construction method for a large vertical shaft according to claim 16, characterized in that, The inner wall of the initial ring is provided with a tunneling equipment mounting seat for installing tunneling equipment, and the top of the liner is lower than the tunneling equipment mounting seat; the top of the bottom sealing structure extends above the bottom ring beam to be integrated with the launching structure.

18. The construction method for a large vertical shaft according to claim 15, characterized in that, The height of the lining along the vertical shaft direction is greater than the thickness of the lining along the radial direction; the thickness of the bottom ring beam along the radial direction is greater than the thickness of the lining along the radial direction.

19. The construction method for a large vertical shaft according to claim 14, characterized in that, In the process of constructing tension piles, the horizontal distance between the tension pile and the well shaft to be formed is less than or equal to the diameter of the tension pile.

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