Mechanical sinking well assembly type shaft segment assembling method and segment structure

Abstract

The application discloses a mechanical sinking well assembly type vertical shaft segment assembling method and a segment structure, and belongs to the technical field of segment assembling methods for vertical shafts.The method comprises the following steps: S1, prefabricating maintenance and reinforcement segment blocks, support shoe ring segment blocks and standard ring segment blocks, and synchronously arranging embedded steel plates M1, embedded steel plates M2, embedded support shoe steel plates and annular bolt embedded parts; S2, welding and pouring a steel sharp corner ring on a construction site, synchronously arranging a steel strand anchoring end joint box, welding a No.1 annular reinforcing steel plate and a No.2 annular reinforcing steel plate, and pressing a rubber mucus stopping plate between the two steel plates; S3, sequentially arranging shear pins and long bolts on shear pin holes and long bolt holes on the upper surface of the steel sharp corner ring, and spacing the shear pins and the long bolts, with the long bolts being higher than the steel sharp corner ring; S4, assembling a bottom reinforcement ring; and S5, assembling an upper standard ring.The method can overcome problems such as a complicated assembling method process, difficulty in guaranteeing precision, low efficiency and easy safety hazards.

Description

Technical Field

[0001] The present invention relates to the technical field of vertical shaft engineering, and in particular to a mechanical caisson assembled vertical shaft segment assembly method and a segment structure. Background Art

[0002] As urban underground space development and municipal engineering construction continue to advance, demand for vertical shafts, critical pathways connecting the underground and the surface, is growing. Traditional shaft construction techniques, such as diaphragm walls and pile foundations, are increasingly limited by site and environmental protection requirements.

[0003] Caisson construction, a common vertical shaft construction technique, relies on the shaft's own gravity, or additional external force to overcome shaft wall friction, or simultaneously utilizes measures such as air curtains and thixotropic slurry jackets to sink the shaft to the designed elevation. Caisson construction is simple and requires a small construction site, but as a dynamic foundation project, problems such as deflection, sudden subsidence, stagnant subsidence, and over-sinking often arise during construction. Furthermore, excavation within the caisson shaft is often carried out manually or mechanically, and the shaft sinking process can easily cause significant and uncontrollable disturbance and damage to the surrounding soil. Minimizing the impact of shaft excavation on buildings has become a major challenge in urban deep shaft construction.

[0004] With the development of mechanized construction technology, the mechanical caisson method has gradually become popular. The mechanical caisson method is a new method of sinking vertical shaft excavation that uses a mechanical arm to perform swing excavation of the stratum underwater and assemble prefabricated segments at the same time. The mechanical caisson method uses mechanical excavation and prefabricated segments for assembly, which can effectively solve the shortcomings of traditional caissons such as large sinking resistance, uncontrolled posture, and large environmental disturbance, greatly improving construction efficiency. However, the current structural design of prefabricated vertical shaft segments for mechanical caissons mostly refers to traditional full-ring caisson segments or shield-assembled segments. The existing prefabricated segment designs of similar underground projects contain many special functional blocks, the connection form is not easy to operate, and there is a conflict between traditional caisson sinking assistance measures and prefabricated segment assembly. Specifically, traditional caissons utilize an integral annular segment structure with no segmented design. This requires only the prefabrication and sinking of the entire ring, eliminating the technical challenges of aligning and fastening the segments within the ring. While shield segments are segmented, their segmentation (e.g., standard, adjacent, and capping block combinations) and stress characteristics (primarily bearing radial earth pressure) differ fundamentally from mechanical caisson segments (which bear vertical friction, water and soil pressure, and self-superimposed loads). Furthermore, shield segments are arranged horizontally and assembled as a single unit using a shield machine, eliminating the need for segment position adjustment and temporary fixation while suspended at high altitude. However, mechanical caisson segments must be suspended and assembled within a vertical shaft, facing unique challenges such as hoisting stability control, multi-degree-of-freedom fine-tuning, and connection reliability under dynamic loads.

[0005] In addition, the existing assembly method also has a cumbersome process, complex operation, involves a large number of fine operations, resulting in low assembly construction efficiency, and in actual operation, affected by human factors, construction environment and tool equipment precision and other factors, the assembly precision is difficult to be stably guaranteed, and error accumulation is prone to occur, and a series of safety hazards are caused under complex working conditions, so that the existing mechanical sinking well assembly type shaft segment structure and assembly method are difficult to meet the needs of today's complex and variable mechanized construction engineering.

[0006] Therefore, based on the construction characteristics and process of the mechanical sinking well method, the mechanical sinking well assembly type shaft segment assembly method and segment structure are provided to solve the above technical problems. SUMMARY

[0007] The main purpose of the present application is to provide a mechanical sinking well assembly type shaft segment assembly method and segment structure, which can overcome the problems of the existing mechanical sinking well assembly type shaft segment structure connection form, the conflict between the traditional sinking well sinking aid and the assembly type shaft segment assembly, the cumbersome assembly method process, the difficulty in ensuring the precision, the low efficiency and the easy occurrence of safety hazards.

[0008] The present application solves the above technical problems by adopting the following technical solutions:

[0009] A mechanical sinking well assembly type shaft segment assembly method, comprising:

[0010] S1. Preparing segment blocks: preparing maintenance and reinforcement segment blocks, support shoe ring blocks and standard ring segment blocks, synchronously setting embedded steel plates M1, embedded steel plates M2, embedded support shoe steel plates and ring bolt embedded parts;

[0011] S2. Welding and pouring steel blade angle ring concrete on site: welding and pouring steel blade angle ring on the construction site, synchronously installing steel strand anchor end connector boxes, welding No. 1 ring-shaped reinforcing steel plate and No. 2 ring-shaped reinforcing steel plate, and pressing rubber mastic plate between the two steel plates;

[0012] S3. Installing steel blade angle ring shear pin and long bolt: installing shear pin and long bolt in shear pin hole and long bolt hole on the upper surface of the steel blade angle ring in sequence, and spacing between the two, and the long bolt is higher than the specified height of the steel blade angle ring (about one ring segment height higher);

[0013] S4. Assembling the bottom reinforcing ring;

[0014] S5. Assembling the upper standard ring.

[0015] Preferably, the specific operation process of the S4 step comprises:

[0016] S41. Placing and installing shear pin, longitudinal long bolt, gasket and connecting nut on the assembled segment;

[0017] S42. Pre-assemble segments on the ground and install elastic rubber gaskets: Use a hoist to ensure that the arc length of the upper edge of the A1, A2, and A3 segments is shorter than the arc length of the lower edge, and that the arc length of the upper edge of the B1, B2, and B3 segments is longer than the arc length of the lower edge.

[0018] S43. Assemble A1, A2, and A3;

[0019] S44. Assemble B1, B2, and B3. After assembly, the clockwise order is A1, B1, A2, B2, A3, and B3.

[0020] S45. Install the annular diagonal bolts;

[0021] S46. Welding embedded steel plate M1 and embedded steel plate M2;

[0022] S47. Seal the bolt holes with quick-drying cement: After the installation of the annular oblique bolts, the reinforced segments are connected into a ring. The bolt holes are sealed with quick-drying cement. After the strength is reached, the caisson segments are sunk to ensure that they do not fall off during the sinking process.

[0023] Preferably, the specific operation process of step S5 includes:

[0024] S51. Place and install shear pins, longitudinal full-length bolts, washers, and connecting nuts on the assembled segments;

[0025] S52. Pre-assemble pipe segments on the ground and install elastic rubber gaskets: Use a hoist to ensure that the arc length of the upper edge of the A1, A2, and A3 pipe segments is less than the arc length of the lower edge, and the arc length of the upper edge of the B1, B2, and B3 pipe segments is greater than the arc length of the lower edge.

[0026] S53. Assemble A1, A2, and A3;

[0027] S54. Assemble B1, B2, and B3. After assembly, the clockwise order is A1, B1, A2, B2, A3, and B3.

[0028] S55. Install the annular diagonal bolts;

[0029] S56. Seal the bolt holes with quick-drying cement: After the annular oblique bolts are installed, the standard annular segments are connected into a ring. The bolt holes are sealed with quick-drying cement. After the strength is reached, the caisson segments are sunk to ensure that they do not fall off during the sinking process.

[0030] Preferably, in the steps S4 and S5, the A1, A2, and A3 segments are assembled first, and then the B1, B2, and B3 segments are assembled. When assembling the B1, B2, and B3 segments, the positioning-locking auxiliary structure is installed.

[0031] The positioning-locking auxiliary structure includes a first positioning buckle, a second positioning buckle, a locking steel cable and a locking motor;

[0032] The positioning clip 1 is set on the lower edge of the outer wall of the B1, B2, and B3 pipe segments to be installed, and the positioning clip 2 is set on the upper edge of the outer wall of the assembled pipe segments. Each B1, B2, and B3 pipe segment block is installed with 2 to 4 positioning clips 1. The number of positioning clips 1 and positioning clips 2 is the same, and the center connection line is parallel to the axis of the pipe segment structure.

[0033] The positioning clip 2 is used to install the locking motor, one end of the locking steel cable is fixed to the positioning clip 1, and the other end is fixed to the locking motor; the locking motor pulls the locking steel cable to make the positioning clip 1 of the B1, B2, and B3 pipe segment blocks to be installed approach the positioning clip 2, thereby realizing traction during the lifting process, ensuring that the shear pins and longitudinal full-length bolts on the upper edge of the assembled pipe segments pass through the B1, B2, and B3 pipe segment blocks to be installed; after the B1, B2, and B3 pipe segment blocks reach the predetermined position, the locking motor applies a fixed locking force F or adopts displacement control and sets a fixed locking force F protection value to ensure axial locking with the lower pipe segment block, thereby facilitating further fixation of the longitudinal full-length bolts.

[0034] Preferably, the fixed locking force F applied by the locking motor is estimated using the following formula:

[0035]

[0036] Where, F k is the segment locking resistance, ρ is the average density of reinforced concrete of the segment; H is the segment ring width; R is the outer radius of the segment; r is the inner radius of the segment; μ is the friction resistance of the circumferential contact surface between the segments; S' is the contact area of ​​the lateral slopes of adjacent segments.

[0037] A segment structure for an assembled caisson shaft, assembled and combined based on any of the above-mentioned mechanical caisson assembled shaft segment assembly methods, including a steel blade angle ring, a bottom reinforcement ring, and an upper standard ring; the segment structure has a total of N rings, numbered 0, 1, 2, ..., N from bottom to top; the steel blade angle ring, the bottom reinforcement ring, and the upper standard ring are bolted together in sequence from bottom to top; the steel blade angle ring is located at the bottom of the segment structure as ring 0 and is bolted to the bottom reinforcement ring numbered 1

[0038] Preferably, the steel blade angle ring is a wedge-shaped structure that is wide at the top and narrow at the bottom, and includes six steel blade foot blocks T1, T2, T3, T4, T5 and T6; the central angle of the steel blade foot blocks is 36°-72°, and each block can adopt the same structural central angle size or a symmetrical special-shaped structure;

[0039] The steel blade angle ring body is reinforced concrete with Q235B steel plate, a No. 1 annular reinforcing steel plate with a height of 300-450 mm and a thickness of 30 mm is installed at the bottom of the outer arc surface, a No. 2 annular reinforcing steel plate with a height of 200 mm and a thickness of 15 mm is installed above the No. 1 annular reinforcing steel plate, the outer arc surfaces of the two steel plates are flush, and the No. 2 annular reinforcing steel plate is overlaid with an L-shaped rubber mastic stop plate between the steel blade foot and the split outer plate;

[0040] An anchor end connector box of a steel strand is installed at the center of the steel blade foot split block, and the position can be adjusted by the construction unit on site; a shear pin hole is arranged every 20° central angle of the steel blade angle ring, and a long bolt hole is arranged between every two holes, which are all conical countersunk hole structures.

[0041] Preferably, the bottom reinforcing ring is n rings in total, numbered 1, 2, …, n from bottom to top.

[0042] The bottom reinforcing ring is composed of six identical reinforcing segment blocks A1, B1, A2, B2, A3, and B3 in a clockwise direction, and the front projection is an isosceles trapezoid, each segment block is flipped by 180° to be the form of the adjacent segment block.

[0043] The central angle of the reinforcing segment block is 60°, the ring width H is 1000-1500 mm, the ring surface has no wedge amount, the lining circular ring is assembled with a staggered joint angle of 20°; 36 same size conical countersunk holes are arranged on the whole ring surface, 18 of which are shear pin holes, and 18 of which are M27 longitudinal through bolt holes, which are arranged alternately; 12 M27 ring bolts are arranged on each ring, and the hand hole is located on the outer arc surface of the segment block; the bottom reinforcing ring is a reinforced concrete structure with a concrete strength grade greater than C40 and a permeability resistance grade P12.

[0044] Preferably, rectangular embedded steel plates M1 and M2 are embedded in the inner surface of the reinforcing segment block; the embedded steel plate M1 is located on the upper and lower edges of the segment block, and there are three blocks on the upper and lower edges and coaxial correspondence, the upper edge of the three blocks on the upper edge and the lower edge of the three blocks on the lower edge are flush with the upper and lower edges of the segment block; the middle one of the three embedded steel plates M1 on the upper and lower edges is located in the middle of the segment block, and the centers of the other two blocks are located at an included angle of 20° with the center of the segment block and the center of the caisson structure.

[0045] The embedded steel plate M1 has a ring length of 1000 mm, a vertical height of 200 mm, and a thickness of 20 mm, and is implanted into the segment block concrete through anchor reinforcement; the embedded steel plate M2 is arranged along the inner edge of the segment block, and three blocks (a total of six blocks) are embedded at equal intervals on each of the two inclined edges, one edge is flush with the inclined edge, and the other edge is perpendicular to the inclined edge; the embedded steel plate M2 has a length of 200 mm, a width of 200 mm, and a thickness of 20 mm, and is implanted into the segment block concrete through anchor reinforcement.

[0046] Preferably, the second and third rings of the bottom reinforcement ring serve as support shoe rings; the 6 reinforcement segments of the support shoe ring are pre-embedded with support shoe steel plates at intervals, and each ring has a total of 3 support shoe ring blocks with pre-embedded support shoe steel plates, which are used to suspend a mechanical caisson boring machine; the support shoe steel plates are pre-embedded in the middle of the inner edge of the support shoe ring block, and 4 pieces are pre-embedded in a rectangular shape; the support shoe steel plates are rectangular steel plates with a length of 500-600mm, a width of 500-600mm, and a thickness of 30mm, and are implanted into the block concrete through anchor bars + anchor plates.

[0047] Preferably, the upper standard ring is composed of 6 identical standard ring segment blocks A1, B1, A2, B2, A3, and B3 in a clockwise direction, and the front projection is an isosceles trapezoid. Each block is flipped 180° to form an adjacent block; the central angle of each standard ring segment block is 60°, the ring width H is 1000-1500mm, the ring surface has no wedge-shaped amount, the lining rings are staggered and the staggered angle is 20°; the entire ring surface is provided with 36 tapered countersunk holes of the same size, 18 of which are shear pin holes and 18 are M27 longitudinal full-length bolt holes, and the two are arranged at intervals; each ring is provided with 12 M27 circumferential bolts, and the hand hole is located on the outer arc surface of the segment; the upper standard ring is a reinforced concrete structure with a concrete strength grade greater than C40 and a water-resistance grade of P12.

[0048] Preferably, the shear pin is made of a steel-plastic composite material, consisting of an inner steel core and an outer ABS wrapping; the inner steel core is a hollow steel tube with an inner diameter of 50-60mm, a thickness of 5mm, and a length of 200-250mm; the outer surface of the outer ABS wrapping is threaded, and is in the shape of a drum with small ends and a small middle; the longitudinal full-length bolt is used for longitudinal connection of the bottom reinforcement ring or the upper standard ring, and is a solid steel bar with external threads at the upper and lower ends, with a length h slightly smaller than the ring width H (Hh=10-20mm), connected by a nut and a washer The segments are connected by two M27 annular oblique bolts, which are connected into a ring through annular bolt embedded parts embedded in the segments, with a total of 12 bolts per ring. One end of the annular oblique bolt has an external thread and the other end has a nut. The annular bolt embedded parts are ABS with internal threads. The two are processed in a matching manner, and the fitting clearance is precision grade. The longitudinal full-length bolts, washers, connecting nuts, annular bolt embedded parts and annular oblique bolts are all anti-corrosive with zinc-based chromate coating with a thickness of not less than 4.6μm.

[0049] Preferably, when the reinforced segment blocks, support shoe ring blocks and standard ring segment blocks are cast, two segment hoisting holes are reserved on the upper and lower sides; I-shaped hoisting rods are embedded in the hoisting holes, and the bearing capacity of each hoisting hole is not less than 10t; elastic rubber sealing pads are pre-installed in the blocks for waterproofing between the blocks.

[0050] Preferably, the shear pins are composed of an inner steel core and an outer ABS sheath made of a thermoplastic plastic material, and are used to perform positioning during the assembly of adjacent segments while meeting specified shear resistance requirements, wherein:

[0051] The inner steel core is a hollow steel tube, the outer surface of the outer ABS is provided with a thread, and the thickness along the thread of the outer ABS gradually decreases along the two ends.

[0052] The present invention provides a method for assembling segments of a prefabricated caisson shaft and a segment structure. Compared with the prior art, the present invention has the following advantages:

[0053] 1. By optimizing the segment connection components, the present invention can overcome the problems of complicated assembly process, difficulty in ensuring accuracy, low efficiency and easy safety hazards, and provide important technical support for subsequent mechanical caisson construction.

[0054] 2. The present invention provides a wedge-shaped structure that is wide at the top and narrow at the bottom on the steel blade angle ring, which can effectively reduce the soil resistance when the caisson is sinking, making it easier to break through the soil and sink. At the same time, No. 1 and No. 2 annular reinforcing steel plates are provided on the outer arc surface and covered with L-shaped rubber stop plates, which can enhance the structural strength and waterproof performance of the steel blade angle ring, thereby ensuring the stability and sealing of the caisson during the sinking process, and ultimately improving the safety and reliability of the caisson construction.

[0055] 3. The present invention designs the bottom reinforcement ring and the upper standard ring into an isosceles trapezoidal structure composed of the same blocks, and adopts a staggered assembly method with a staggered angle of 20°, which can enhance the overall stiffness and stability of the segment ring and reduce stress concentration; at the same time, shear pin holes, long bolt holes and annular bolts are provided to achieve reliable connection between the segment blocks, thereby improving the bearing capacity and anti-seepage performance of the segment structure, and ultimately ensuring the structural safety and normal use of the caisson shaft.

[0056] 4. The present invention installs a positioning-locking auxiliary structure, including a positioning clip, a locking steel cable and a locking motor, when assembling the B1, B2 and B3 pipe segment blocks. It can accurately position the pipe segment blocks by pulling the positioning clips during the lifting process, thereby solving the problem that the dead weight of the elastic rubber sealing gasket cannot fall to the expected point; the locking force applied by the locking motor can ensure the axial locking of the pipe segment blocks, which is convenient for subsequent bolt fixation, thereby improving the accuracy and efficiency of pipe segment assembly, reducing error accumulation, and ultimately avoiding safety hazards caused by assembly problems, ensuring construction quality and safety.

[0057] 5. The present invention adopts a mechanical caisson method combined with an assembled pipe segment structure, which can effectively solve the problems of large sinking resistance, uncontrolled posture, and large environmental disturbance in traditional caissons; by optimizing the pipe segment connection components and assembly methods, it can simplify the assembly process, reduce the difficulty of fine operations, and improve the efficiency of assembly construction. At the same time, the auxiliary structure is used to ensure the assembly accuracy and avoid errors caused by human factors and environmental factors, thereby overcoming the problems of complicated assembly processes, difficult to ensure accuracy, and low efficiency in the existing technology, and ultimately providing reliable technical support for mechanical caisson construction, and promoting the mechanization and efficiency of shaft engineering construction.

[0058] 5. Based on the designed segment structure, this application can quickly estimate the locking force required to fix the segment block, so as to facilitate the regulation of the motor to achieve rapid locking. At the same time, it can also quickly calculate the descent height during the segment assembly and descent process under its own weight, facilitating the actual segment assembly operation in caisson construction to improve construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0060] Figure 1 It is a schematic diagram of the overall process of the present invention;

[0061] Figure 2 This is a schematic cross-sectional view of the ring assembly structure of the present invention;

[0062] Figure 3 This is a schematic cross-sectional view of the steel blade angle ring structure of the present invention;

[0063] Figure 4 This is a schematic cross-sectional view of the annular reinforced steel plate connection structure of the present invention;

[0064] Figure 5 This is a schematic diagram of the distribution of shear pin holes on the steel blade angle ring of the present invention;

[0065] Figure 6 It is a side plan view of the steel blade angle ring connection structure of the present invention;

[0066] Figure 7 This is a schematic diagram of the installation distribution of the embedded steel plate structure of the present invention;

[0067] Figure 8 Schematic side section of the shear pin structure of the present invention;

[0068] Figure 9 It is a schematic diagram of the side section installation layout of the longitudinal through-length bolt structure of the present invention;

[0069] Figure 10A plan view of the annular bolt structure of the present application;

[0070] Figure 11 A side cross-sectional view of the annular bolt embedded structure of the present application;

[0071] Figure 12 A plan view of the elastic rubber sealing gasket structure of the present application;

[0072] Figure 13 A pipe segment construction and assembly operation schematic view of the present application. DETAILED DESCRIPTION

[0073] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The embodiments in the present application and the features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0074] In the embodiments, refer to Figures 1 to 13 .

[0075] As Figure 1 shown, in order to overcome the problems of the existing mechanical method sinking well assembly type shaft segment structure connection form inconvenience, traditional sinking well sinking assisting measures conflict with assembly type shaft segment assembly, assembly method process is complicated, precision is difficult to guarantee, efficiency is low and safety hidden danger is easy to cause and other problems, the present application provides a construction assembly method of mechanical method sinking well assembly type shaft segment structure, comprising the following steps:

[0076] S1. Precast segment block: precast maintenance and reinforcement segment block, support boot ring block and standard ring segment block, simultaneously set embedded steel plate M1, embedded steel plate M2, support boot steel plate, annular bolt embedded part and I-shaped hoisting rod.

[0077] S2. Weld steel blade angle ring on site: weld steel blade angle ring block (T1-T6) on site, pour concrete and simultaneously install steel strand anchoring end connector box, weld No. 1 annular reinforcing steel plate (300-450mm x 30mm) and No. 2 annular reinforcing steel plate (200mm x 15mm), the outer arc surfaces of the two are flush and cover L-shaped rubber stop plate.

[0078] S3. Install connecting piece: install shear pin and long bolt on the upper surface of the steel blade angle ring to the conical countersunk hole.

[0079] S4. Assemble bottom reinforcing ring:

[0080] Rings 1 to 4 are assembled with through-holes (to ensure mechanical caisson excavation equipment and stable caisson structure), and the remaining rings are assembled with 20° staggered joints. During hoisting, the upper arc length of the A-type segments (A1 / A2 / A3) should be less than the lower arc length, and the upper arc length of the B-type segments (B1 / B2 / B3) should be greater than the lower arc length.

[0081] First assemble the A-type segments, then use the positioning-locking auxiliary structure (including positioning clips, locking cables and motors) to pull the B-type segments into place accurately;

[0082] The 2nd to 3rd rings are used as gripper rings, and the embedded gripper steel plates need to be aligned up and down;

[0083] After tightening the annular oblique bolts, the bolt holes are sealed with quick-drying cement.

[0084] After the bottom reinforcement ring is assembled into a ring, the embedded steel plate M1 at the lower edge of the inner surface of the newly assembled bottom reinforcement ring is welded to the embedded steel plate M1 at the upper edge of the inner surface of the bottom reinforcement ring below, and the embedded steel plates M2 are welded between the segments of the bottom reinforcement ring in the same ring.

[0085] The 2nd and 3rd rings are for installing the mechanical caisson excavation equipment. To ensure the excavation of the mechanical caisson excavation equipment and the stability of the caisson structure, the 1st, 2nd, 3rd and 4th pipe segments are assembled without any seams, and the remaining rings are assembled with a 20° staggered seam.

[0086] S5. Assemble the upper standard ring: The process is the same as step (4), but there is no need to weld the embedded steel plate.

[0087] In addition, in a specific embodiment, a shield receiving shaft is a circular shaft with a diameter of 15m and a depth of 50m. The geology is interbedded with silty clay and sand and gravel. The settlement is controlled at ±50mm and the joint leakage rate is ≤0.1%. After technological innovation, the mechanical caisson construction method of this application is adopted, and the steel blade angle ring is designed to be wedge-shaped blocks (T1-T6, 60° central angle), with No. 1 (30mm) and No. 2 (15mm) annular reinforcement steel plates, and L-shaped rubber stop plates are clamped; the bottom reinforcement ring (rings 1-9) is made of C50 / P12 concrete, with a ring width of 1500mm, and 36 tapered holes to achieve the spaced arrangement of shear pins and M27 bolts; the 3rd and 4th rings are support shoe rings; the bottom reinforcement ring and the upper standard ring are both pre-assembled on the ground, A / B type pipe segment arc length control, 20° staggered assembly (1 to 4 through-seam assembly) and quick-drying cement sealing, which reduces on-site errors and maintenance time compared with traditional processes; the B type pipe segment is equipped with a positioning-locking system with an 80kN locking force.

[0088] Practice has shown that assembling traditional full-ring caisson segments or shield assembly segments can result in problems such as single-ring assembly time ≥12 hours, joint errors exceeding 15mm, and inclinations reaching 1.2%. Using the assembly process proposed in this application reduces single-ring assembly time to 5.5 hours (a 54% improvement), reducing labor by 50%; joint errors ≤3mm (an 80%-88% improvement), inclination 0.3% (a 70%-75% improvement), flatness 4mm / 2m (a 67% improvement), and bolt stress fluctuations reduced by 62.5%. This significantly improves efficiency and precision, optimizes structural stress and economy, and provides a standardized and efficient solution for urban vertical shaft construction with complex geology.

[0089] On the other hand, the present invention also provides a mechanical caisson assembled shaft segment structure, such as Figure 3 As shown, the assembly method based on the above embodiment realizes the structural assembly combination, and the specific structure includes:

[0090] (1) Steel blade angle ring (0 ring): The vertical section is a wedge-shaped structure with a wide top and a narrow bottom. It is composed of 6 steel blade foot blocks (T1, T2, T3, T4, T5 and T6) to form a wedge-shaped ring. The central angle of the steel blade foot blocks is 36° to 72°. It can be of the same configuration (i.e., T1, T2, T3, T4, T5 and T6 are the same, with a central angle of 60°) or symmetrical heterogeneous configuration (T1 = T4, T2 = T5, T3 = T6). The main body is reinforced concrete with Q235B steel plates, and a No. 1 ring reinforcement steel plate is set at the bottom of the outer arc surface. (The height is 300-450mm and the thickness is 30mm), and a No. 2 annular reinforcing steel plate (the height is 200mm and the thickness is 15mm) is provided on the upper part. The outer arc surfaces of the No. 1 annular reinforcing steel plate and the No. 2 annular reinforcing steel plate are flush, and a rubber slurry stop plate is pressed between the No. 2 annular reinforcing steel plate and the main structure of the steel blade angle ring to isolate the mud inside the mechanical caisson assembled vertical shaft segment from the thixotropic mud behind the wall. The vertical section of the rubber slurry stop plate is L-shaped, one side is pressed by the No. 2 annular reinforcing steel plate, and the other side is parallel to the outer normal of the steel blade angle ring.

[0091] Furthermore, a steel strand anchor end joint box is installed at the center position of each steel blade foot block (referring to the angle bisector of the center of the steel blade foot block) for connecting to the lifting system to ensure the stability of the lifting of the entire mechanical caisson assembled shaft segment structure. The steel strand anchor end joint box is located in the middle of the steel blade foot block, and the specific position can be adjusted by the construction unit according to the on-site conditions.

[0092] For further reference, Figure 4 The steel blade angle ring has a tapered countersunk hole structure at every 10° central angle on its annular surface (serving as shear pin holes and long bolt holes, the shear pin holes and the long bolt holes are arranged at intervals, and the shear pin holes and the long bolt holes can also be used for each other). It is set to a cone shape to facilitate installation and positioning, which can improve the accuracy and efficiency of subsequent segment assembly.

[0093] In a specific embodiment, the positions of the shear pin holes and long bolt holes in the first ring of pipe segments connected to the steel blade foot ring can also be adjusted. At this time, the shear pin holes and long bolt hole embedded parts need to be placed before the concrete is poured inside the steel blade foot ring.

[0094] It can be further explained here that when the symmetrical isomerization (T1=T4, T2=T5, T3=T6) is adopted, T1, T2, T4, and T5 are 72°, and T3 and T6 are 36°, and they are arranged symmetrically at intervals.

[0095] (2) Bottom reinforcement ring (a total of n rings, n = 5 to 10 rings, numbered from bottom to top as 1, 2, ..., n): Reference Figure 6 , consists of 6 identical reinforced pipe segment blocks (A1 / B1 / A2 / B2 / A3 / B3), which are A1, B1, A2, B2, A3, B3 in clockwise direction. The front is an isosceles trapezoid. Each reinforced pipe segment block is flipped 180° to become the form of the adjacent reinforced pipe segment block (for example, A1 is flipped 180° to become the form of B1).

[0096] Furthermore, the central angle of each reinforced segment block (the central angle of the middle part of the reinforced segment block in the vertical direction) is α=60°, the ring width H of the bottom reinforcement ring is 1000~1500mm, no wedge is set on the ring surface, and the lining ring is assembled with staggered joints, and the staggered angle is 20°.

[0097] Furthermore, the entire annular surface is provided with 36 tapered countersunk holes of the same size, of which 18 shear pin holes are used to place shear pins, and 18 long bolt holes are used to place M27 longitudinal full-length bolts. The shear pins and longitudinal full-length bolts are arranged at intervals.

[0098] Furthermore, each bottom reinforcement ring is provided with 12 M27 circumferential bolts (the hand holes are located on the outer arc surface of the segment).

[0099] In addition, it should be noted that during specific use, the bottom reinforcement ring is a reinforced concrete structure with a concrete strength grade greater than C40 and a water-resistance grade of P12.

[0100] Further, in a specific embodiment, referring to Figure 7 Embedded parts on the inner surface of the bottom reinforcement ring (embedded steel plates M1 and M2 are embedded on the inner surface):

[0101] (a) Three embedded steel plates M1 (1000mm×200mm×20mm) are embedded at the upper and lower edges of the inner surface of each reinforced segment block. The embedded steel plates M1 at the upper and lower edges are coaxially distributed. The upper edges of the three embedded steel plates M1 at the upper edge are flush with the upper edge of the reinforced segment block, and the lower edges of the three embedded steel plates M1 at the lower edge are flush with the lower edge of the reinforced segment block. The middle one of the three embedded steel plates M1 at the upper and lower edges is arranged in the middle of the reinforced segment block. The central angle between the centers of the remaining two embedded steel plates M1, the center of the reinforced segment block, and the center of the caisson structure is 20°. The embedded steel plates M1 have a circumferential length of 1000mm along the reinforced segment block, a vertical height of 200mm, and a thickness of 20mm. Anchor bars are used to embed them into the concrete of the reinforced segment block.

[0102] (b) Three embedded steel plates M2 (200mm×200mm×20mm) are arranged at equal distances on the two oblique sides of the inner surface of each reinforced segment block, that is, a total of six embedded steel plates M2 are arranged on the inner surface of each reinforced segment block. One side of the embedded steel plate M2 is flush with the oblique side of the reinforced segment block, and the other side is perpendicular to the oblique side. The embedded steel plate M2 is 200mm long, 200mm wide and 20mm thick, and is embedded in the concrete of the reinforced segment block with anchor bars.

[0103] Furthermore, in a specific embodiment, the second and third rings of the bottom reinforcement ring are used as gripper rings, which are used to install the main machine of the mechanical caisson equipment, wherein the six reinforcement pipe segment blocks of the gripper ring are pre-embedded with gripper steel plates at intervals (all A1, A2 and A3 blocks are installed or all B1, B2 and B3 are installed), and each ring of the gripper ring has a total of three gripper ring blocks with pre-embedded gripper steel plates, wherein the gripper ring blocks are used to suspend the mechanical caisson boring machine by installing gripper steel plates, and the gripper steel plates are pre-embedded and installed in the middle of the inner edge of the gripper ring blocks, and four pieces are pre-embedded and installed in a rectangular manner, that is, the second to third rings are gripper rings, and four gripper steel plates (500-600mm×500-600mm×30mm) are pre-embedded in the middle of the inner edge.

[0104] Furthermore, the shoe steel plate is a rectangular steel plate with a length of 500-600 mm, a width of 500-600 mm, and a thickness of 30 mm. Anchor bars + anchor plates are used to embed into the concrete of the reinforced pipe segments.

[0105] (3) Upper standard ring: It is composed of 6 identical standard ring segments (A1 / B1 / A2 / B2 / A3 / B3), which are A1, B1, A2, B2, A3, and B3 in clockwise order. The front projection presents an isosceles trapezoid, that is, the structural parameters are the same as those of the bottom reinforcement ring. Each standard ring segment is flipped 180° to form the adjacent standard ring segment, but there is no embedded steel plate M1 / M2 and support shoe steel plate.

[0106] Specifically, refer to Figure 5 In terms of specific structure, the central angle of each standard ring segment (the central angle of the middle part of the reinforced segment segment in the vertical direction) is α=60°, the ring width H of the upper standard ring is 1000~1500mm, no wedge is set on the ring surface, the lining ring is assembled with staggered joints, and the staggered joint angle is 20°. The entire ring surface of the upper standard ring is equipped with 36 tapered countersunk holes of the same size, of which 18 shear pin holes are used to place shear pins, and 18 long bolt holes are used to place M27 longitudinal full-length bolts. The shear pins and longitudinal full-length bolts are arranged at intervals.

[0107] In addition, in a specific embodiment, each upper standard ring is also provided with 12 M27 annular bolts (the hand holes are located on the outer arc surface of the pipe segment). At this time, the upper standard ring is a reinforced concrete structure, the concrete strength grade is greater than C40, and the water-resistance grade is P12.

[0108] (4) Connection system: including shear pins, longitudinal full-length bolts, annular oblique bolts, etc., of which:

[0109] (a) Shear pin: Reference Figure 8 , is a steel-plastic composite structure (steel core + ABS shell), consisting of an internal steel core and an outer layer of ABS (thermoplastic) with a threaded surface;

[0110] Specifically, the internal steel core of the structure is a hollow steel tube with an inner diameter of 50-60mm, a thickness of 5mm, and a length of 200-250mm. The outer surface of the structure is wrapped with ABS and processed with threads, forming a drum shape with small ends and a middle part. In actual use, after the shear pins are inserted into this type of structure, on the one hand, it can play the role of positioning the subsequent pipe segments, and on the other hand, it can also play the role of connecting the upper and lower adjacent pipe segments and resisting shear.

[0111] (b) Longitudinal full-length bolt: Reference Figure 9 , used for longitudinal connection of the bottom reinforcement ring (upper standard ring), its structure is a solid steel bar with external threads at the upper and lower ends. The length h of the longitudinal full-length bolt is slightly smaller than the ring width H of the bottom reinforcement ring (upper standard ring), meeting the length condition: h = H-(10~20mm);

[0112] And in the specific implementation process, the full-length connection is achieved by connecting nuts and washers.

[0113] (c) Annular oblique bolts: Reference Figure 10 and Figure 11 , using M27 specifications, precisely matched with the embedded ABS sleeve (that is, the segment blocks of the same ring segment are connected to the adjacent segment blocks by two M27 annular oblique bolts);

[0114] Specifically, the circumferential inclined bolts are connected to form a ring through the circumferential bolt embedded parts embedded in the reinforced pipe piece blocks (standard ring pipe piece blocks), and the circumferential inclined bolts are 12 in total per ring.

[0115] At this time, the circumferential inclined bolts have external threads at one end and nuts at the other end, the circumferential bolt embedded parts are ABS with internal threads, and the circumferential bolt and the circumferential bolt embedded part need to be processed in pairs, with a precise gap, and the bolt is processed with a sleeve.

[0116] All metal connecting parts (longitudinal through bolts, washers, connecting nuts, circumferential bolt embedded parts, and circumferential inclined bolts) are coated with a zinc-based chromate anticorrosive coating (thickness ≥ 4.6 μm).

[0117] (5) General structure: each pipe piece block (reinforced pipe piece block, support shoe ring block, and standard ring pipe piece block) has two lifting holes (bearing capacity ≥ 10 t) reserved on the upper and lower surfaces during pouring, with an I-shaped lifting rod embedded inside; the blocks are connected by elastic rubber sealing pads as shown in Figure 12 for waterproofing between the pipe piece blocks.

[0118] In further embodiments, with reference to Figure 2 , the mechanical sinking well assembly type vertical shaft pipe piece structure has N rings, numbered 0, 1, 2,..., N from bottom to top, and the steel blade angle ring, the bottom reinforcement ring, and the upper standard ring sequentially fasten and connect the prefabricated pipe pieces by bolts, so that the pipe pieces form a stable whole vertical shaft structure; each pipe piece block is installed with two embedded grouting holes, which are used to inject thixotropic mud behind the pipe piece during excavation and to replace mud grouting after excavation is completed; at this time, the steel blade angle ring (0 ring) is located at the lowermost part of the mechanical sinking well assembly type vertical shaft pipe piece structure and is connected to the bottom reinforcement ring (number 1) by bolts.

[0119] Further, based on the above pipe piece assembly method and assembly structure, the assembly of the bottom reinforcement ring (including the support shoe ring) includes the following steps:

[0120] L11, installing shear pins, longitudinal through bolts, washers, and connecting nuts on the assembled pipe pieces;

[0121] L12, ground pre-assembled pipe piece assembly, installing elastic rubber sealing pads: on-site, through the lifting machine, ensure that the upper arc length of A1, A2, and A3 pipe piece blocks is less than the lower arc length, and the upper arc length of B1, B2, and B3 pipe piece blocks is greater than the lower arc length;

[0122] L13, assembling A1, A2, and A3;

[0123] L14, assembling B1, B2, and B3;

[0124] L15, install the annular oblique bolts;

[0125] L16, welding embedded steel plate M1 and embedded steel plate M2;

[0126] L17, quick-drying cement to seal the bolt holes: After the installation of the annular oblique bolts is completed, the reinforced segments are connected into a ring in blocks, and the bolt holes are sealed with quick-drying cement. The caisson segments can be sunk only after reaching a certain strength, and ensure that the caisson segments do not fall off during the sinking process.

[0127] The gripper plates in the gripper rings (2nd and 3rd rings) must be aligned vertically during installation.

[0128] Furthermore, based on the above segment assembly method and assembly structure, the assembly of the upper standard ring includes the following steps:

[0129] L21, place and install shear pins, longitudinal full-length bolts, washers, and connecting nuts on the assembled segments;

[0130] L22, ground pre-assembled segments, installation of elastic rubber gaskets: on-site use of a hoist to ensure that the arc length of the upper edge of the A1, A2, and A3 segments is less than the arc length of the lower edge, and the arc length of the upper edge of the B1, B2, and B3 segments is greater than the arc length of the lower edge;

[0131] L23, assemble A1, A2, A3;

[0132] L24, assemble B1, B2, B3;

[0133] L25, install the annular oblique bolts;

[0134] L26, quick-drying cement to seal the bolt holes: After the installation of the annular oblique bolts is completed, the standard ring segments are connected into a ring in blocks, and the bolt holes are sealed with quick-drying cement. The caisson segments can be sunk only after reaching a certain strength, and it is ensured that the caisson segments do not fall off during the sinking process.

[0135] Furthermore, during the assembly of the bottom reinforcement ring and the upper standard ring, the A1, A2, and A3 segments are assembled first, followed by the B1, B2, and B3 segments, to facilitate the formation of the entire segment ring. However, during the assembly of the B1, B2, and B3 segments, due to the presence of elastic rubber gaskets between the adjacent A1, A2, and A3 segments, the B1, B2, and B3 segments have difficulty falling to the desired position under their own weight. During the assembly of the B1, B2, and B3 segments, a positioning and locking auxiliary structure is installed.

[0136] It can be further explained at this point that the positioning-locking auxiliary structure includes a first positioning buckle, a second positioning buckle, a locking steel cable and a locking motor.

[0137] During use, refer to Figure 13Positioning clip 1 is installed on the lower edge of the outer wall of the B1, B2, and B3 segments to be installed, and positioning clip 2 is installed on the upper edge of the outer wall of the assembled segments. Each B1, B2, and B3 segment block is installed with 2 to 4 positioning clips 1. The number of positioning clips 1 and positioning clips 2 is the same. The center line of positioning clip 1 and positioning clip 2 is parallel to the axis of the mechanical caisson assembled shaft segment structure.

[0138] Among them, the positioning buckle 2 is used to install the locking motor, one end of the locking cable is fixed to the positioning buckle 1, and the other end is fixed to the locking motor;

[0139] Therefore, the locking motor can pull the locking steel cable to make the positioning buckle 1 of the B1, B2, and B3 segment blocks being installed move closer to the positioning buckle 2, thereby achieving the traction of the B1, B2, and B3 segment blocks during the lifting process, and ensuring that the shear pins and longitudinal full-length bolts on the upper edge of the assembled segments accurately pass through the B1, B2, and B3 segment blocks being installed.

[0140] When the B1, B2, and B3 segment blocks reach the predetermined position (i.e., the side of the installed A1, A2, and A3 segment blocks), a fixed locking force F is applied by the locking motor (or displacement control is used to set the fixed locking force F protection value) to ensure the axial locking of the B1, B2, and B3 segment blocks with the segment blocks below, facilitating the further fixing and locking of subsequent longitudinal through-length bolts.

[0141] By controlling the locking motor, a fixed locking speed (such as v = 0.2 ~ 0.5m / min) can be applied, and the fixed locking force F protection value can be set to 1.2F at the same time. k , that is, F<1.2F k This can avoid sudden sinking and damage to the elastic rubber sealing gasket during assembly.

[0142] The fixed locking force F applied by the locking motor is estimated using the following formula:

[0143]

[0144] Where, F k is the segment locking resistance; ρ is the average density of reinforced concrete of the segment; H is the segment ring width (vertical height); R is the outer radius of the segment; r is the inner radius of the segment; μ is the friction resistance of the circumferential contact surface between the segments; S' is the contact area of ​​the lateral slopes of adjacent segments.

[0145] Furthermore, the segment locking resistance can be determined by computer based on the drop height h1 of the B1, B2, and B3 segments after they contact the A1, A2, and A3 segments.F k :

[0146]

[0147] Where h1 is the real-time descent height of the B1, B2, and B3 segments; θ1 is the central angle corresponding to the upper surface of the B1, B2, and B3 segments; and θ2 is the central angle corresponding to the lower surface of the B1, B2, and B3 segments.

[0148] Further calculation, when F k When <0, the descending height h can be obtained by assembling the B1, B2 and B3 segments by their own weight. k for:

[0149]

[0150] In a further embodiment, a shield receiving shaft adopts a circular vertical shaft with a depth of 50m and is constructed by the mechanical caisson method of the present application. The segment ring width H is 1.5m, the segment inner radius is 7m, the segment outer radius is 7.45m, the upper surface of the B1, B2, and B3 segments corresponds to a central angle of 62°, the lower surface corresponds to a central angle of 56°, and the average density of the segment reinforced concrete is 2500kg / m 3 The friction coefficient of the circumferential contact surface is 0.5. According to calculations, the weight of a single segment is about 30.8kN, and the lateral contact area is about 1.33m 2 The friction force is about 15.4kN. The self-weight drop height hk of a single segment is 0.65m based on the balance between its own weight and the work done by friction. During actual assembly, the self-weight drop heights of B1, B2, and B3 are 0.62m, 0.67m, and 0.64m, respectively, and the errors with the calculated results are all within 10%.

[0151] Further calculations show that, based on the principle of balance between the self-weight component and friction of a single segment, the locking resistance Fk of a single segment when descending 1.3m is approximately 28.7kN. This result can guide the force setting of the locking motor when assembling the B1, B2, and B3 segments to ensure stable axial locking of the segments.

[0152] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0153] In addition, it should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0154] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or schemes in which A and B are satisfied at the same time. In addition, in the embodiments of the present invention, "multiple" refers to more than two. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A method for assembling mechanical caisson assembled shaft segments, characterized in that: include: S1. Prefabricated segment blocks: Prefabricated curing and reinforcement segment blocks, gripper ring blocks, and standard ring segment blocks, with simultaneous installation of embedded steel plates M1, M2, embedded gripper plates, and annular bolt embedded parts; S2. On-site welding and pouring of steel angle ring concrete: The steel angle ring is welded and poured on-site. The strand anchor end joint box is installed simultaneously. Ring reinforcement plates No. 1 and No. 2 are welded, and a rubber grouting plate is placed between the two plates. S3. Install the shear pins and long bolts on the steel blade angle ring: Install the shear pins and long bolts in the shear pin holes and long bolt holes on the top surface of the steel blade angle ring, spacing them apart and ensuring the long bolts are higher than the specified height of the steel blade angle ring. S4. Assemble the bottom reinforcement ring; S5. Assemble the upper standard ring; The specific operation process of the S4 step includes: S41. Place and install shear pins, longitudinal full-length bolts, washers, and connecting nuts on the assembled segments. S42. Pre-assemble segments on the ground and install elastic rubber gaskets: Use a hoist to ensure that the arc length of the upper edge of the A1, A2, and A3 segments is shorter than the arc length of the lower edge, and that the arc length of the upper edge of the B1, B2, and B3 segments is longer than the arc length of the lower edge. S43. Assemble A1, A2, and A3; S44. Assemble B1, B2, and B3. After assembly, the clockwise order is A1, B1, A2, B2, A3, and B3. S45. Install the annular diagonal bolts; S46. Welding embedded steel plate M1 and embedded steel plate M2; S47. Use quick-drying cement to seal the bolt holes and sink the caisson segments after the strength reaches the required level. The specific operation process of step S5 includes: S51. Place and install shear pins, longitudinal full-length bolts, washers, and connecting nuts on the assembled segments; S52. Pre-assemble segments on the ground and install elastic rubber gaskets: Use a hoist to ensure that the arc length of the upper edge of the A1, A2, and A3 segments is shorter than the arc length of the lower edge, and that the arc length of the upper edge of the B1, B2, and B3 segments is longer than the arc length of the lower edge. S53. Assemble A1, A2, and A3; S54. Assemble B1, B2, and B3. After assembly, the clockwise order is A1, B1, A2, B2, A3, and B3. S55. Install the annular diagonal bolts; S56. Use quick-drying cement to seal the bolt holes and sink the caisson segments after the strength reaches the required level. In the steps S4 and S5, the positioning-locking auxiliary structure is installed when assembling the B1, B2, and B3 segments; The positioning-locking auxiliary structure includes a positioning clip 1 installed on the lower edge of the outer wall of the segments to be assembled B1, B2, and B3, a positioning clip 2 installed on the upper edge of the outer wall of the assembled segments, a locking steel cable, and a locking motor; Each B1, B2, and B3 segment is equipped with 2 to 4 first-positioning clips, and the number of second-positioning clips is the same, and the center line is parallel to the shaft axis; The locking motor is provided on the positioning buckle 2, and the two ends of the locking cable are fixed to the positioning buckle 1 and the locking motor respectively; The locking motor pulls the locking cable to move the positioning buckle 1 closer to the positioning buckle 2, ensuring that the shear pins and longitudinal full-length bolts on the upper edge of the assembled segments pass through the segments to be installed; After the segments are in place, the locking motor applies a fixed locking force. F Axial locking is achieved.

2. The method for assembling mechanical caisson assembled vertical shaft segments according to claim 1, characterized in that: The fixed locking force applied by the locking motor F Use the following formula to estimate: Where, F k is the segment locking resistance, ρ is the average density of reinforced concrete of the segment; H is the segment ring width; R is the outer radius of the segment; r is the inner radius of the segment; μ is the friction resistance of the circumferential contact surface between the segments; S' is the contact area of ​​the lateral slopes of adjacent segments.

3. A mechanically assembled vertical shaft segment structure for caisson, assembled based on the assembly method for mechanically assembled vertical shaft segments for caisson according to any one of claims 1-2, characterized in that: It includes a steel edge angle ring, a bottom reinforcement ring and an upper standard ring bolted from bottom to top; The total segment structure N Rings, numbered from bottom to top, are 0 to N ; The steel blade angle ring is ring 0, the bottom reinforcement ring is rings 1 to n, and the upper standard ring is rings n+1 to N.

4. The mechanical caisson assembled vertical shaft segment structure according to claim 3, characterized in that: The steel blade corner ring is composed of 6 steel blade foot blocks, which are numbered T1 to T6; The steel blade foot is divided into blocks with a central angle of 36°-72°, and the main body is reinforced concrete with steel plates wrapped around it; A No. 1 annular reinforcement steel plate is provided at the bottom of the outer arc surface, and a No. 2 annular reinforcement steel plate is provided above it. The outer arc surfaces of the two steel plates are flush, and an L-shaped rubber slurry stop plate is pressed between the No. 2 annular reinforcement steel plate and the outer steel plate of the steel blade foot block; A steel strand anchorage end joint box is provided at the center of each block; Conical countersunk holes are provided on the annular surface of the steel blade corner ring at intervals of 10° from the central angle, which serve alternately as shear pin holes and long bolt holes.

5. The mechanical caisson assembled vertical shaft segment structure according to claim 3, characterized in that: The upper standard ring is composed of 6 identical standard ring segments, numbered A1, B1, A2, B2, A3, B3 in clockwise order; Each piece has a central angle of 60°, a ring width of H=1000-1500mm, and is assembled with staggered joints and a staggered angle of 20°; The annular surface is provided with 36 conical countersunk holes, 18 of which are for installing shear pins and 18 for installing M27 longitudinal full-length bolts, which are arranged at intervals; Each ring is equipped with 12 M27 ring-shaped oblique bolts, and the hand holes are located on the outer arc surface; The pipe segments are made of reinforced concrete of C40 or above with anti-seepage grade P12.

6. The mechanical caisson assembled vertical shaft segment structure according to claim 5, characterized in that: The reinforced pipe segment blocks, support shoe ring blocks and standard ring pipe segment blocks are each provided with two lifting holes on the upper and lower surfaces, and an I-shaped lifting rod with a bearing capacity of ≥10t is embedded in the hole. The assembly surface of each block is pre-installed with an elastic rubber sealing gasket.

7. The mechanical caisson assembled vertical shaft segment structure according to claim 5, characterized in that: The shear pins consist of an inner steel core and an outer ABS sheath made of thermoplastic material, and are used to position adjacent segments during assembly while meeting specified shear resistance requirements, wherein: The inner steel core is a hollow steel tube, the outer surface of the outer ABS is provided with threads, and the thickness along the threads of the outer ABS gradually decreases along the two end directions.

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