High-efficiency split-starting method for ultra-large diameter shield in extreme space

Abstract

The present invention provides an efficient split start method for an ultra-large diameter shield in an extreme space, which relates to the technical field of shield construction, including measuring and obtaining the shield length Ls1, the length of the downhole trolley Ls2, and calculating the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section, and then excavating the shield start space according to the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section, wherein the shield start space includes the working shaft and the dark excavation section perpendicular to the side wall of the working shaft. The efficient split start method for an ultra-large diameter shield in an extreme space of the present invention provides a design method for the minimum longitudinal length of the structure under the split start condition of a 14m-class ultra-large diameter shield, effectively reducing the amount of open excavation work in a station or a working shaft, reducing the cost of engineering construction, and by intensively arranging the necessary equipment for split start on the downhole trolley and adopting continuous excavation construction, the efficient split start of a 14m-class ultra-large diameter shield is achieved, reducing construction risks and saving construction period.

Description

Technical Field

[0001] The invention relates to the technical field of shield construction, in particular to a high-efficiency split starting method for an ultra-large diameter shield in an extreme space. Background Art

[0002] 14m-class (shield excavation diameter ≥ 14m) super-large diameter shield tunnels have become the first choice for the construction of urban highway tunnels, railway tunnels and highway-railway combined tunnels due to their advantages of comprehensive and efficient use of underground space resources. The total length of the 14m-class super-large diameter shield is generally greater than 100m, and the length of the structural space that meets its overall starting cannot be less than the total length of the shield. At present, due to the limited starting space, more and more shield engineering projects use secondary and multiple split starting technologies. Although the split starting technology saves the shield starting space, it also brings about adverse effects such as prolonged shield starting process and increased risks. How to shorten the space required for shield starting to a minimum to reduce the structural civil engineering cost, and ensure the excavation efficiency and safety of the 14m-class super-large diameter shield split start in the extreme space is a key issue that needs to be solved in super-large diameter shield construction.

[0003] Regarding the research on the split-launching technology of shield, the existing technical literature ("Split-launching technology of large-diameter slurry shield", Li Huaihong, Building Construction, Vol. 33, No. 12, December 2011) discloses the arrangement method of the main equipment of the 11.58m diameter slurry shield on the shaft structure plate, the trolley in the shaft and the ground trolley. However, the starting shaft is equipped with the shield main machine, connecting beam and trolley at the same time, and the longitudinal length is not the minimum length for split-launching, and the shaft structure can be further optimized.

[0004] The prior Chinese patent (authorization announcement number: CN113982608B, invention patent name: Ultra-deep narrow vertical shaft shield split start construction method) proposed a split start method for a shield machine with an excavation diameter of 8.64m in a narrow vertical shaft. The P2.1 mud pump, synchronous grouting system, shield tail grease system, main engine room and cables are arranged on the left and right structural platforms in the vertical shaft. In the three steps of its split start, the position of the rear supporting system needs to be repeatedly adjusted, and the rear supporting trailer needs to be assembled and debugged multiple times underground and above the well. Although this patent solves the problem of split start of the shield machine in a narrow vertical shaft, it also brings about the problem of discontinuity of shield construction under multiple split starts, resulting in low construction efficiency and high risk.

[0005] The prior Chinese patent (authorization announcement number: CN109184706B, invention patent name: A method for split-starting of a large-diameter shield machine) proposed a method in which the shield hydraulic system, grouting system, control cabinet, etc. are arranged on a multi-section trolley underground, and other components are placed on a ground trolley, and the shield is started twice. This patent focuses on the arrangement method of the split-starting shield components on the trolleys above and below the well, but lacks the split-starting limit space and the efficient split-starting method of the shield.

[0006] Based on the prior art including the above, the present invention provides a method for efficient split starting of an ultra-large diameter shield machine in an extreme space. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides an efficient split starting method for an ultra-large diameter shield in an extreme space, which solves the problem that the split starting is implemented in the main structure of the station or in the open-cut section plus the shield starting shaft. The length of the starting space depends on the design length of the station or the open-cut section, which is not the minimum space required for the split starting. Multiple split starting will lead to discontinuity in the shield construction, and the excavation efficiency and safety need to be improved.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: an efficient split starting method for a super-large diameter shield machine in an extreme space, wherein the shield machine used for the efficient split starting includes: a shield body, a downhole trolley, a connecting bridge, and a ground trolley;

[0009] The efficient split-initiation method specifically includes the following steps:

[0010] S1, measure and obtain the shield length Ls1, the length of the trolley Ls2, and calculate the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section by formula ①;

[0011] ①;

[0012] Among them, La in formula ① is the longitudinal length of the structure; La1 is the longitudinal length of the working shaft; La2 is the longitudinal length of the dark excavation section, Ls is the length of the underground shield, Ls1 is the length of the shield body; Ls2 is the length of the trolley going down to the well;

[0013] S2, excavating a shield starting space according to the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section, wherein the shield starting space includes the working shaft and the dark excavation section perpendicular to the side wall of the working shaft;

[0014] S3. The split-body excavation starts in the following order: assembling the shield down into the well, pushing the shield into the dark excavation section, hoisting the trolley down into the well, starting the split-body excavation, hoisting the connecting bridge and the ground trolley down into the well, and normal excavation.

[0015] Preferably, the trolley for going down the well is designed according to three layers: upper, middle and lower, and each layer of the trolley for going down the well is divided into left and right sides;

[0016] The upper layer on the left side is arranged with: the first frequency conversion cabinet, the first transformer, and the first fan;

[0017] The left middle layer is arranged: hydraulic system hydraulic oil tank, foam system, synchronous B fluid tank;

[0018] The lower level on the left is arranged with: hydraulic system pump station and bentonite system;

[0019] The upper layer on the right side is arranged with: the second frequency conversion cabinet, the second transformer, and the second fan;

[0020] The middle level on the right is arranged as follows: shield operation room and grease injection system;

[0021] The lower layer on the right side is arranged with: synchronous grouting system, synchronous A liquid tank, cooling water system and continuous belt.

[0022] Preferably, a compressed air system and a continuous belt conveyor are arranged on the connecting bridge; and a segment hoisting machine, a box culvert assembly machine, and a high-voltage cable storage device are arranged on the ground trolley.

[0023] Preferably, after the excavation length of the split initial excavation is greater than the length of the shield machine, the connecting bridge and the ground trolley are hoisted down into the well.

[0024] Preferably, the shield body includes a blade disc, a front middle shield, and a shield tail.

[0025] Preferably, before the shield is assembled in the well, a starting base is installed at the inner bottom of the working well, and two sets of auxiliary jacks are used to push the shield into the dark excavation section.

[0026] Preferably, before the trolley is hoisted down the well, the starting reaction frame is first hoisted and installed in place. The trolley is divided into a lower frame, a middle frame and an upper frame, and the equipment on the lower frame, the middle frame and the upper frame are arranged in the factory. The hoisting of the trolley down the well includes: first hoisting the lower frame down the well, then hoisting the middle frame and the upper frame down the well in turn for assembly, and connecting the equipment on the lower frame, the middle frame and the upper frame with the shield body. After the shield is debugged, the split starting excavation is carried out.

[0027] The present invention provides an efficient split starting method for ultra-large diameter shield in extreme space, which has the following beneficial effects:

[0028] 1. The efficient split starting method of the ultra-large diameter shield in extreme space of the present invention provides a design method for the minimum longitudinal length of the structure under the condition of split starting of the 14m-class ultra-large diameter shield, which effectively reduces the amount of open excavation engineering in the station or working shaft and reduces the cost of engineering construction. In addition, by intensively arranging the equipment necessary for split starting on the shaft trolley and adopting continuous excavation construction, the efficient split starting of the 14m-class ultra-large diameter shield is achieved, which reduces the construction risk and saves the construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of a shield machine used in the efficient split-starting method for ultra-large diameter shield tunneling in extreme space proposed by the present invention;

[0030] Figure 2 It is a schematic longitudinal section diagram of the limit space of the shield starting method of the limit space ultra-large diameter shield proposed by the present invention;

[0031] Figure 3 It is a schematic diagram of the assembly of the shield body downhole in the efficient split launching method of the ultra-large diameter shield in the extreme space proposed by the present invention;

[0032] Figure 4 It is a schematic diagram of the shield body being pushed into the dark excavation section in the efficient split starting method of the ultra-large diameter shield machine in the extreme space proposed by the present invention;

[0033] Figure 5 This is a schematic diagram of the hoisting and lowering of the lowering trolley into the shaft in the efficient split starting method of the ultra-large diameter shield machine in the extreme space proposed by the present invention;

[0034] Figure 6 This is a schematic diagram of the connecting bridge and the ground trolley hoisting down the shaft in the efficient split starting method of the ultra-large diameter shield in the extreme space proposed by the present invention;

[0035] Figure 7 It is a schematic diagram of the intensive arrangement of the equipment on the left side of the downhole trolley of the efficient split starting method of the ultra-large diameter shield machine in the extreme space proposed by the present invention;

[0036] Figure 8 This is a schematic diagram of the intensive arrangement of equipment on the right side of the shaft trolley for the efficient split starting method of the ultra-large diameter shield machine in extreme space proposed by the present invention.

[0037] Among them, 10, working shaft; 11, dark excavation section; 12, shield section; 20, shield body; 201, cutter head; 202, front middle shield; 203, shield tail; 204, starting base; 21, downhole trolley; 211, lower frame; 212, middle frame; 213, upper frame; 22, connecting bridge; 23, ground trolley; 30, first frequency conversion cabinet; 31, first transformer; 32, first fan; 33, hydraulic system hydraulic Oil tank; 34. Foam system; 35. Synchronous B liquid tank; 36. Hydraulic system pump station; 37. Bentonite system; 40. Second frequency converter cabinet; 41. Second transformer; 42. Second fan; 43. Shield operation room; 44. Grease injection system; 45. Synchronous grouting system; 46. Synchronous A liquid tank; 47. Cooling water system; 48. Continuous belt; 51. Auxiliary jack; 61. Starting reaction frame; 71. Segment. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Embodiment 1:

[0040] In the embodiment of the present invention, Figure 1 The shield machine used in the high-efficiency split start shown in the figure includes: a shield body 20, a downhole trolley 21, a connecting bridge 22, and a ground trolley 23. The shield body 20, the downhole trolley 21, the connecting bridge 22, and the ground trolley 23 are assembled and spliced ​​linearly to form the shield machine.

[0041] The efficient split starting method of the ultra-large diameter shield machine in extreme space specifically includes the following steps:

[0042] The shield length Ls1 and the length of the trolley Ls2 (which represents the longitudinal length of the longest equipment among the trolley 21, the connecting bridge 22 and the ground trolley 23) are measured and obtained, and the longitudinal length La1 of the working shaft and the longitudinal length La2 of the underground excavation section are calculated by formula ①.

[0043] ①;

[0044] Among them, La in formula ① is the longitudinal length of the structure; La1 is the longitudinal length of the working shaft; La2 is the longitudinal length of the dark excavation section, Ls is the length of the underground shield, Ls1 is the length of the shield body; Ls2 is the length of the trolley going down to the shaft. The minimum value of La that satisfies formula ① is the longitudinal length of the limit space structure. According to the longitudinal length La of the structure, the excavation can only have the limit space of the working shaft 10.

[0045] In order to further reduce the workload of excavating the shield starting space, the shield starting space can be excavated according to the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section. The specific design of the shield starting space is as follows: Figure 2 As shown, it includes a working shaft 10 and a dark excavation section 11 perpendicular to the side wall of the working shaft 10. The longitudinal length of the working shaft 10 is La1, and the longitudinal length of the dark excavation section 11 is La2. During the actual excavation process, the depth and width of the working shaft 10 are selected according to the design requirements, and it must meet the requirements of the shield body 20, the descent trolley 21, the connecting bridge 22, and the ground trolley 23 for going down into the shaft. The dark excavation section 11 is cylindrical in shape, and its diameter must meet the requirements of the longitudinal passage of the shield body 20, the descent trolley 21, the connecting bridge 22, and the ground trolley 23.

[0046] Compared with the structure of only excavating a vertical shaft, the longitudinal length of the working shaft 10 excavated in this embodiment is further reduced, achieving the purpose of extreme space, effectively reducing the open excavation volume of the station or the working shaft, and reducing the construction cost.

[0047] The specific steps of the split start include: assembling the shield downhole, pushing the shield into the dark excavation section, hoisting the trolley downhole, starting the split excavation, hoisting the connecting bridge and the ground trolley downhole, and starting the split excavation in the order of normal excavation.

[0048] like Figure 6 As shown, the pipe segments 71 need to be installed during the initial excavation and normal excavation of the split excavation to ensure the internal stability of the dark excavation section 11 and the shield section 12 to avoid collapse accidents.

[0049] Compared with the traditional shutdown or intermittent split starting method, the above method can ensure the continuity and safety of shield tunneling, thereby achieving the goal of efficient split starting.

[0050] Various auxiliary equipment is also required during the operation of the shield machine. In order to ensure that the auxiliary equipment used by the shield machine can be installed reasonably, more rear-end supporting trolleys are set up when arranging the traditional shield machine's rear-end supporting system. This is mainly because the tunnel space is limited and cannot meet the height of 2 or 3-layer trolleys, resulting in a loose layout of the rear-end supporting trolleys, wasting precious space resources.

[0051] In the specific design, the longitudinal length of the working shaft is 30m, the length of the dark excavation section is 15m, the length of the shield section is 4562m, the length of the shield body is 13.5m, the length of the trolley going down to the shaft is 27m, the length of the connecting bridge is 30m, and the length of the ground trolley is 37m (the ground trolley is divided into two sections, each section is 18.5m).

[0052] In this embodiment, Figure 7 and Figure 8As shown, the trolley 21 is designed according to the upper, middle and lower layers, and each layer of the trolley 21 is divided into left and right sides; the upper layer on the left is arranged with the first frequency conversion cabinet 30, the first transformer 31, and the first fan 32; the middle layer on the left is arranged with the hydraulic system hydraulic oil tank 33, the foam system 34, and the synchronous B liquid tank 35; the lower layer on the left is arranged with the hydraulic system pump station 36 and the bentonite system 37; the upper layer on the right is arranged with the second frequency conversion cabinet 40, the second transformer 41, and the second fan 42; the middle layer on the right is arranged with the shield operation room 43 and the grease injection system 44; the lower layer on the right is arranged with the synchronous grouting system 45, the synchronous A liquid tank 46, the cooling water system 47, and the continuous belt 48; the length of the shield trolley 21 obtained by this is also the shortest, and the 14m-class super-large diameter shield tunnel can meet the height of the 3-layer trolley, and the intensive arrangement of the subsequent supporting systems is gradually feasible. The trolley is designed according to the upper, middle and lower layers, and each layer is divided into left and right sides for equipment arrangement. The power distribution equipment is arranged on the upper level, mainly considering the humidity and safety of the working environment; the middle level considers the convenience of personnel and material access, and is mainly arranged with the operation room, grease injection system, etc.; the lower level is arranged with equipment with high environmental noise, such as motors and pumps, and is as full as possible.

[0053] Some non-essential auxiliary equipment during the shield tunneling process can be installed on the connecting bridge 22 and the ground trolley 23. In one embodiment, a compressed air system and a continuous belt conveyor are arranged on the connecting bridge 22; a segment hoisting machine, a box culvert assembly machine, and a high-voltage cable storage device are arranged on the ground trolley 23.

[0054] In one embodiment, after the excavation length of the split excavation is greater than the length of the shield machine, that is, the total length of the working shaft 10, the dark excavation section 11, and the shield section 12 is greater than the length of the shield machine, the process of hoisting the connecting bridge and the ground trolley into the well is carried out. Only after the excavation length of the split excavation is greater than the length of the shield machine, the space required for hoisting the connecting bridge and the ground trolley into the well is met.

[0055] In one embodiment, if Figure 3 As shown, the shield body 20 includes a cutter head 201 , a front middle shield 202 , and a shield tail 203 . The cutter head 201 , the front middle shield 202 , and the shield tail 203 are assembled in the working well 10 .

[0056] In one embodiment, before the shield is assembled in the well, a starting base 204 is installed on the inner bottom of the working well 10. Figure 4 As shown, two sets of auxiliary jacks 51 are used to push the shield body into the dark excavation section. The starting base 204 is a support track. The shield body 20 slides on the starting base 204 and relies on the two sets of auxiliary jacks 51 to push the shield body into the dark excavation section.

[0057] In one embodiment, before the trolley is hoisted down the well, Figure 5As shown, the starting reaction frame 61 is first hoisted and installed in place, the trolley 21 for going down into the well is divided into a lower frame 211, a middle frame 212, and an upper frame 213, and the equipment on the lower frame 211, the middle frame 212, and the upper frame 213 are arranged in the factory. The hoisting and lowering of the trolley for going down into the well includes: first hoisting the lower frame 211 down into the well, and then hoisting the middle frame 212 and the upper frame 213 down into the well for assembly, and connecting the equipment on the lower frame 211, the middle frame 212, and the upper frame 213 with the shield body 20. After the shield debugging is completed, the split starting excavation is carried out.

[0058] The equipment on the lower frame 211, the middle frame 212 and the upper frame 213 are arranged in the factory, and the three integral components of the lower frame 211, the middle frame 212 and the upper frame 213 are convenient for hoisting and going down into the well.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An efficient split starting method for ultra-large diameter shield in extreme space, characterized by: The shield machine for efficient split-body starting use comprises: a shield body (20), a downhole trolley (21), a connecting bridge (22), and a ground trolley (23); the downhole trolley (21) is designed according to three layers: upper, middle, and lower, and each layer of the downhole trolley (21) is divided into left and right sides; The upper layer on the left side is arranged with: a first frequency conversion cabinet (30), a first transformer (31), and a first fan (32); The left middle layer is arranged as follows: hydraulic system hydraulic oil tank (33), foam system (34), synchronous B fluid tank (35); The lower layer on the left side is arranged with: hydraulic system pump station (36), bentonite system (37); The upper layer on the right side is arranged with: a second frequency conversion cabinet (40), a second transformer (41), and a second fan (42); The middle layer on the right side is arranged as follows: the shield operation room (43) and the grease injection system (44); The lower layer on the right side is arranged as follows: synchronous grouting system (45), synchronous A liquid tank (46), cooling water system (47), and continuous belt (48); The efficient split-initiation method specifically includes the following steps: S1, measure and obtain the shield length Ls1, the length of the trolley Ls2, and calculate the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section by formula ①; ①; Among them, La in formula ① is the longitudinal length of the structure; La1 is the longitudinal length of the working shaft; La2 is the longitudinal length of the dark excavation section, Ls is the length of the underground shield, Ls1 is the length of the shield body; Ls2 is the length of the trolley going down to the well; S2, excavating a shield starting space according to the longitudinal length La1 of the working shaft and the longitudinal length La2 of the dark excavation section, wherein the shield starting space includes the working shaft (10) and the dark excavation section (11) perpendicular to the side wall of the working shaft (10); S3. The split-body excavation starts in the following order: assembling the shield down into the well, pushing the shield into the dark excavation section, hoisting the trolley down into the well, starting the split-body excavation, hoisting the connecting bridge and the ground trolley down into the well, and normal excavation.

2. The method for high-efficiency split launching of ultra-large diameter shield in extreme space according to claim 1 is characterized by: A compressed air system and a continuous belt conveyor are arranged on the connecting bridge (22); and a pipe segment hoisting machine, a box culvert assembly machine, and a high-voltage cable storage unit are arranged on the ground trolley (23).

3. The method for high-efficiency split launching of ultra-large diameter shield in extreme space according to claim 1 is characterized by: After the excavation length of the split excavation is greater than the length of the shield machine, the connecting bridge and the ground trolley are hoisted down into the well.

4. The method for high-efficiency split launching of ultra-large diameter shield in extreme space according to claim 1 is characterized by: The shield body (20) comprises a blade disc (201), a front middle shield (202), and a shield tail (203).

5. The method for high-efficiency split launching of ultra-large diameter shield in extreme space according to claim 1 is characterized by: Before the shield is assembled in the well, a starting base (204) is installed on the inner bottom of the working well (10), and two sets of auxiliary jacks (51) are used to push the shield into the dark excavation section.

6. The method for high-efficiency split launching of ultra-large diameter shield in extreme space according to claim 1 is characterized by: Before the trolley is hoisted down into the well, the starting reaction frame (61) is first hoisted and installed in place. The trolley (21) is divided into a lower frame (211), a middle frame (212), and an upper frame (213), and the equipment on the lower frame (211), the middle frame (212), and the upper frame (213) are arranged in the factory. The trolley is hoisted down into the well, including: first hoisting the lower frame (211) down into the well, then hoisting the middle frame (212) and the upper frame (213) down into the well in sequence, and then connecting the equipment on the lower frame (211), the middle frame (212), and the upper frame (213) with the shield body (20). After the shield is debugged, the split excavation is carried out.

Images