Reinforcing structure for large-span underground excavation station to pass through fault fracture zone

Abstract

The utility model provides a reinforcing structure for a large-span underground excavation station to pass through a fault fracture zone, which comprises an earth surface grouting reinforcing body and an in-hole grouting reinforcing body which are arranged in a crossed mode, and the in-hole grouting reinforcing body comprises a peripheral grouting stopping rock disc and an internal reinforcing body. The peripheral grouting stopping rock disc comprises a base plate and side walls connected to the two sides of the base plate, the ground surface grouting reinforcing body is fixedly connected to the side walls, a through hole is formed in the ground surface grouting reinforcing body, and the internal reinforcing body is connected to the ground surface grouting reinforcing body and covers the through hole. A supporting space used for wrapping the underground excavation station is formed among the peripheral grouting stopping rock disc, the earth surface grouting reinforcing body and the internal reinforcing body. The overall structure is simple, construction safety is guaranteed when the station passes through the fault fracture zone, and construction risks are reduced. And the ground surface grouting reinforcing bodies and the in-hole grouting reinforcing bodies are arranged in an intersecting mode, and the reinforcing reliability is good.

Description

Technical Field

[0001] The utility model relates to the technical field of construction engineering, and in particular to a structure for reinforcing a large-span underground excavation station passing through a fault fracture zone. Background Art

[0002] For the reinforcement technology of water-rich fault zones, relevant experts and scholars have conducted a lot of research over the years and have achieved some research results, especially in the fields of railway tunnels, mines and tunnels, but there are few examples of research on grouting technology for urban large-span subway stations crossing water-rich fault fracture zones. Water-rich fault zones are characterized by loose and broken surrounding rocks, poor stability, and abundant groundwater.

[0003] The surrounding structures of large-span subway station tunnels are complex, often with huge traffic flow, numerous municipal pipelines and a large number of buildings. Construction in such strata is prone to water seepage, water gushing and mud bursting, and excessive surface settlement, which seriously threatens the safety of surrounding buildings and structures and affects the construction progress. Therefore, a reliable reinforcement must be proposed for large-span underground excavation stations crossing fault fracture zones. Utility Model Content

[0004] Based on this, in order to solve the technical problems existing in the existing large-span dark-excavated stations, the utility model provides a structure for reinforcing a large-span dark-excavated station passing through a fault fracture zone, and its specific technical solution is as follows:

[0005] A structure for reinforcing a large-span underground excavation station passing through a fault fracture zone, comprising a surface grouting reinforcement body and an in-hole grouting reinforcement body arranged in an intersecting manner, the in-hole grouting reinforcement body comprising an outer grouting-stopping rock plate and an internal reinforcement body, the outer grouting-stopping rock plate comprising a bottom plate and side walls connected to both sides of the bottom plate, the surface grouting reinforcement body being fixedly connected to the side walls, the surface grouting reinforcement body being provided with a through hole, the internal reinforcement body being connected to the surface grouting reinforcement body and covering the through hole, a supporting space for wrapping the underground excavation station is formed between the outer grouting-stopping rock plate, the surface grouting reinforcement body and the internal reinforcement body.

[0006] Furthermore, the surface grouting reinforcement body is vertically spaced with a plurality of surface grouting holes for passing the vertical sleeve valve pipe;

[0007] A left guide hole and a right guide hole are symmetrically arranged on the surface grouting reinforcement body, and a plurality of first in-hole grouting holes are arranged at intervals on the outer grouting stopping rock plate, one end of the first in-hole grouting hole is located on the outer surface of the outer grouting stopping rock plate, and the other end of the first in-hole grouting hole is respectively located in the left guide hole and the right guide hole;

[0008] A plurality of second in-hole grouting holes are arranged at intervals in the internal reinforcement body.

[0009] Furthermore, the diameter of the surface grouting hole is 80mm-100mm.

[0010] Furthermore, the vertical sleeve valve pipe and the grouting holes in the first hole are filled with a first grouting material, and the grouting holes in the second hole are filled with a second grouting material.

[0011] Furthermore, a pressure-isolating expansion mold bag is provided above the surface grouting.

[0012] Furthermore, the lowermost end of the vertical sleeve valve pipe is 0.8-m-1.2m lower than the arch of the underground excavation station, and the horizontal spacing of the surface grouting holes is the diffusion radius of the first grouting material flowing out of the vertical sleeve valve pipe.

[0013] Furthermore, the grouting holes in the first hole and the grouting holes in the second hole are both arranged in at least 4 rows.

[0014] Furthermore, the end of the grouting hole in the second hole is located 3m outside the outer contour of the underground station.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The overall structure is streamlined, and the surface grouting reinforcement body reinforces the broken body of the station tunnel arch, so that the arch top sand layer is consolidated into a whole through slurry, creating conditions for grouting in the tunnel, avoiding the collapse of the grouting hole in the tunnel, saving costs, and avoiding repeated grouting. The outer grouting stop rock plate reinforces the surrounding rock within 3m outside the station to achieve the effect of grouting and water blocking, thereby improving the reinforcement effect and reliability of the internal surrounding rock. The grouting reinforcement body in the tunnel has high stability, thereby ensuring construction safety when the station passes through the fault fracture zone and reducing construction risks. The surface grouting reinforcement body and the grouting reinforcement body in the tunnel are intersected, and the reinforcement reliability is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention can be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily drawn to scale, but the emphasis is placed on illustrating the principles of the embodiments. In different views, the same reference numerals designate corresponding parts.

[0018] Figure 1 It is a schematic diagram of the cross-sectional structure of a structure used for reinforcing a large-span underground excavation station passing through a fault fracture zone in an embodiment of the utility model.

[0019] Figure 2 It is a schematic diagram of the longitudinal section structure of a structure used for reinforcing a large-span underground excavation station passing through a fault fracture zone in an embodiment of the utility model.

[0020] Description of reference numerals:

[0021] 1. Pressure-isolating expansion mold bag; 2. Surface grouting hole; 3. Surface grouting reinforcement body; 4. Grouting hole in the first hole; 5. Grouting hole in the second hole; 6. Internal reinforcement body; 7. Underground excavation station; 8. External grouting rock plate; 9. Left pilot tunnel; 10. Right pilot tunnel. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with its embodiments. It should be understood that the specific implementation methods described here are only used to explain the utility model and do not limit the protection scope of the utility model.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0024] A structure for reinforcing a large-span underground tunnel station passing through a fault fracture zone, comprising a surface grouting reinforcement body 3 and an in-tunnel grouting reinforcement body arranged in an intersecting manner, the in-tunnel grouting reinforcement body comprising an outer grouting-stopping rock plate 8 and an internal reinforcement body 6, the outer grouting-stopping rock plate 8 comprising a base plate and side walls connected to both sides of the base plate, the surface grouting reinforcement body 3 being fixedly connected to the side walls, the surface grouting reinforcement body 3 being provided with a through hole, the internal reinforcement body 6 being connected to the surface grouting reinforcement body 3 and covering the through hole, a supporting space for wrapping the underground tunnel station 7 is formed between the outer grouting-stopping rock plate 8, the surface grouting reinforcement body 3 and the internal reinforcement body 6.

[0025] As a preferred embodiment of the utility model, it may also have the following additional technical features: a plurality of surface grouting holes 2 for passing vertical sleeve valve pipes are vertically spaced on the surface grouting reinforcement body 3;

[0026] The surface grouting reinforcement body 3 is symmetrically provided with a left guide hole 9 and a right guide hole 10, and the outer grouting stop rock plate 8 is provided with a plurality of first in-hole grouting holes 4 at intervals, one end of the first in-hole grouting holes 4 is located on the outer surface of the outer grouting stop rock plate 8, and the other end of the first in-hole grouting holes 4 is respectively located in the left guide hole 9 and the right guide hole 10;

[0027] The internal reinforcement body 6 is provided with a plurality of second in-hole grouting holes 5 at intervals.

[0028] The vertical sleeve valve pipes are arranged in a plum blossom shape with a plane spacing of 1.2m×1.2m.

[0029] As a preferred embodiment of the utility model, it may also have the following additional technical features: the diameter of the surface grouting hole 2 is 80mm-100mm. Preferably, the vertical sleeve valve pipe in the surface grouting hole 2 adopts a PVC pipe with a diameter of 50mm. The diameters of the first hole grouting hole 4 and the second hole grouting hole 5 are both 130mm.

[0030] As a preferred embodiment of the utility model, it may also have the following additional technical features: the vertical sleeve valve pipe and the grouting hole 4 in the first hole are filled with a first grouting material, and the grouting hole 5 in the second hole is filled with a second grouting material.

[0031] As a preferred embodiment of the utility model, it may also have the following additional technical features: a pressure-isolating expansion mold bag 1 is arranged above the surface grouting. Through the above arrangement, the slurry is prevented from flowing upward.

[0032] As a preferred embodiment of the utility model, it may also have the following additional technical features: the lowermost end of the vertical sleeve valve pipe is 0.8-m-1.2m lower than the arch of the underground excavation station 7, and the horizontal spacing of the surface grouting holes 2 is the diffusion radius of the first grouting material flowing out of the vertical sleeve valve pipe.

[0033] As a preferred embodiment of the present utility model, it may also have the following additional technical features: the first hole grouting holes 4 and the second hole grouting holes 5 are both arranged in at least 4 rows.

[0034] As a preferred embodiment of the present utility model, it may also have the following additional technical features: the end of the grouting hole 5 in the second hole is located 3m outside the outer contour of the underground excavation station 7.

[0035] As a preferred embodiment of the utility model, it may also have the following additional technical features: the first grouting material is a mixture of cement-water glass and sulphoaluminate cement slurry. In the cement-water glass double slurry: the water-cement ratio is 0.8-1:1, the volume ratio of cement slurry to water glass is 1-3:1, and the concentration of water glass is 15 degrees Baume-20 degrees Baume. The water-cement ratio of sulphoaluminate cement slurry is 0.8-1.2:1.

[0036] As a preferred embodiment of the utility model, it may also have the following additional technical features: the second grouting material is a mixture of cement slurry and ultrafine cement slurry. The second grouting material is ultrafine cement slurry, and its water-cement ratio is 0.8-1.2:1.

[0037] Specific construction process:

[0038] The technical solution of the utility model is explained by taking a large-span underground excavation station in a certain city that needs to cross a tensile fault zone that is connected to the sea as an example. Figure 1 As shown: it includes the surface grouting reinforcement body 3 and the in-hole grouting reinforcement body.

[0039] The surface grouting reinforcement body 3 is composed of the first grouting material filled in the surface grouting hole 2 and the reinforcement part formed by the first grouting material after diffusion and the surrounding parts of the surface grouting hole 2. The horizontal distance from the surface vertical grouting hole to the outer contour of the arch of the underground excavation station 7 is 3m. The lower end of the surface grouting hole 2 is 0.8m-1.2m lower than the lower end of the arch of the underground excavation station 7. The distance between the two surface grouting holes 2 is the diffusion radius of the first grouting material, which is 1.2m in this embodiment. The surface grouting reinforcement body 3 forms a reinforcement body in the arch sand layer of the underground excavation station 7. An isolation expansion mold bag is set in the upper section of the surface grouting hole 2 to prevent the slurry from flowing up. The first grouting material is cement-water glass double liquid slurry + sulphoaluminate cement slurry. In the cement-water glass double liquid slurry, the water-cement ratio is 0.8-1:1, the volume ratio of cement slurry to water glass is 1-3:1, and the concentration of water glass is 15-20 degrees Baume. The water-cement ratio of the above-mentioned sulphoaluminate cement slurry is 0.8-1.2: 1. The vertical sleeve valve pipe adopts a PVC pipe with a diameter of 50 mm and a drilling hole diameter of 80-100 mm.

[0040] Construction process of surface grouting reinforcement body 3: Before grouting reinforcement construction, on-site grouting experiments should be carried out to determine the optimal ratio of slurry, grouting pressure and diffusion radius of grouting; determine the horizontal and vertical positions of the surface sleeve valve pipe grouting pipe, lay it out on the surface, and number and mark the hole position; after the drilling rig equipment is ready, adjust the drilling rig angle and direction to ensure that the drill rod is vertical and aligned with the hole position for drilling; after drilling to the specified depth (0.8m-1.2m below the arch of the underground excavation station 7), pull out the drill rod, insert the vertical sleeve valve pipe pre-arranged with the pressure-isolating expansion mold bag 1 for grouting (cement-water glass double liquid slurry + sulphoaluminate cement slurry), and the grouting end standard adopts the "quantity and pressure dual control" end standard: the grouting pressure is gradually increased to the designed final pressure, and the grouting is continued for more than 10 minutes. The slurry volume is less than 1 / 4 of the initial slurry volume, and the slurry velocity is less than 25% of the initial velocity. At the same time, the grouting volume is not less than 80% of the designed grouting volume of a single hole.

[0041] The in-hole grouting reinforcement body includes an outer grouting-stopping rock plate 8 and an inner reinforcement body 6. The outer grouting-stopping rock plate 8 is composed of a first grouting material filled in the first in-hole grouting hole 4 and a reinforcement part formed by the first grouting material and the surrounding parts of the in-hole grouting hole after diffusion. The inner reinforcement body 6 includes a second grouting material filled in the second in-hole grouting hole 5 and a reinforcement part formed by the surrounding parts after diffusion of the second grouting material. The outer grouting-stopping rock plate 8 achieves the functions of grouting and water blocking, and improves the internal surrounding rock reinforcement effect and reliability. The inner reinforcement body 6 has high stability, thereby ensuring construction safety when the underground excavation station 7 passes through the fault fracture zone and reducing construction risks.

[0042] The construction process of the grouting reinforcement body in the hole (the outer grouting-stopping rock plate 8 and the inner reinforcement body 6): After the surface grouting reinforcement body 3 is completed, 7 to 14 days later, ensure that the strength of the surface grouting reinforcement body 3 reaches the requirements, and then carry out the grouting in the hole. The left pilot tunnel 9 and the right pilot tunnel 10 are used to lay out the lines to determine the position of the first grouting hole 4 in the hole, and the numbers and marks are carried out. Set up the scaffolding, lay out the drilling rig working platform, adjust the horizontal angle and orientation of the drilling rig, align the hole position, and drill; after drilling to the designated position, grouting (first grouting material) is carried out. The grouting end standard is the same as the surface sleeve valve pipe grouting. After the outer grouting-stopping rock plate 8 reaches the predetermined strength, the left pilot tunnel 9 and the right pilot tunnel 10 are used to lay out the lines to determine the position of the second grouting hole 5 in the hole, and the numbers and marks are carried out. Adjust the horizontal angle and orientation of the drilling rig, align it with the hole position, and start drilling; after drilling to the designated position, perform grouting (second grouting material), and the grouting end standard is the same as before. The first in-hole grouting holes 4 are constructed from the innermost row, and are constructed row by row outward. At the same time, the first in-hole grouting holes 4 and the second in-hole grouting holes 5 in each row are constructed from both ends to the middle. The reinforcement length of the in-hole grouting reinforcement body is 15m per cycle, and the excavation length is 12m. A 3m grouting section is reserved as the grouting stop rock plate for the next cycle.

[0043] The utility model is a reinforcement body proposed for large-span underground excavation stations crossing fault fracture zones. Surface sleeve valve pipe grouting is used to first form a reinforcement body in the fracture zone of the station arch, creating conditions for later grouting in the tunnel to avoid hole collapse and sand burst. The outer grout-stopping rock plate 8 inside and outside the tunnel reinforces the surrounding rock near the outer contour of the station to achieve the effect of grouting and water blocking. The internal reinforcement body 6 reinforces the internal surrounding rock of the station to avoid collapse during construction. Practice has shown that this reinforcement system not only ensures the safety of surrounding buildings and construction during actual construction, but also ensures the construction progress.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The overall structure is streamlined, and the surface grouting reinforcement body 3 reinforces the broken body of the station tunnel arch, so that the arch top sand layer is consolidated into a whole through slurry, creating conditions for grouting in the tunnel, avoiding the collapse of the grouting hole in the tunnel, saving costs, and avoiding repeated grouting. The outer grouting stop rock plate 8 achieves the effect of grouting and water blocking by reinforcing the surrounding rock within 3m outside the station, thereby improving the reinforcement effect and reliability of the internal surrounding rock. The in-tunnel grouting reinforcement body has high stability, thereby ensuring construction safety when the station passes through the fault fracture zone and reducing construction risks. The surface grouting reinforcement body 3 and the in-tunnel grouting reinforcement body are arranged to intersect, and the reliability of reinforcement is good.

[0046] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A structure for reinforcing a large-span underground excavation station passing through a fault fracture zone, characterized in that: It comprises a surface grouting reinforcement body (3) and an in-hole grouting reinforcement body arranged in an intersecting manner, wherein the in-hole grouting reinforcement body comprises an outer grouting-stopping rock plate (8) and an inner reinforcement body (6), wherein the outer grouting-stopping rock plate (8) comprises a bottom plate and side walls connected to both sides of the bottom plate, wherein the surface grouting reinforcement body (3) is fixedly connected to the side walls, wherein the surface grouting reinforcement body (3) is provided with a through hole, wherein the inner reinforcement body (6) is connected to the surface grouting reinforcement body (3) and covers the through hole, and a supporting space for wrapping a dark excavation station (7) is formed between the outer grouting-stopping rock plate (8), the surface grouting reinforcement body (3) and the inner reinforcement body (6).

2. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 1 is characterized in that: The surface grouting reinforcement body (3) is provided with a plurality of surface grouting holes (2) at vertical intervals for passing vertical sleeve valve pipes; The surface grouting reinforcement body (3) is symmetrically provided with a left guide hole (9) and a right guide hole (10), and the outer grouting-stopping rock plate (8) is provided with a plurality of first in-hole grouting holes (4) at intervals, one end of each of the first in-hole grouting holes (4) is located on the outer surface of the outer grouting-stopping rock plate (8), and the other end of each of the first in-hole grouting holes (4) is located in the left guide hole (9) and the right guide hole (10), respectively; A plurality of second in-hole grouting holes (5) are arranged at intervals in the internal reinforcement body (6).

3. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 2 is characterized in that: The diameter of the surface grouting hole (2) is 80 mm to 100 mm.

4. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 3 is characterized in that: The vertical sleeve valve pipe and the first hole grouting hole (4) are both filled with a first grouting material, and the second hole grouting hole (5) is filled with a second grouting material.

5. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 4 is characterized in that: A pressure-isolating expansion mold bag (1) is arranged above the surface grouting.

6. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 5 is characterized in that: The lowermost end of the vertical sleeve valve pipe is 0.8-m-1.2m lower than the arch of the underground excavation station (7), and the horizontal spacing of the surface grouting holes (2) is the diffusion radius of the first grouting material flowing out of the vertical sleeve valve pipe.

7. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 6 is characterized in that: The first hole grouting holes (4) and the second hole grouting holes (5) are both arranged in at least four rows.

8. The structure for reinforcing a large-span underground excavation station passing through a fault fracture zone according to claim 7 is characterized in that: The end of the grouting hole (5) in the second hole is located 3m outside the outer contour of the underground excavation station (7).

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