CN213016346U - Processing structure for reinforcing failure of shield receiving end in high-pressure water-rich sand layer - Google Patents

Abstract

The utility model provides a shield constructs in rich water sand bed of high pressure and receives end reinforcement inefficacy's processing structure. The processing structure is constructed before the shield machine reaches the continuous wall close to the tunnel portal and the tunnel portal continuous wall is broken, and specifically comprises an AB type double-component polyurethane grouting pipe, a WSS deep hole grouting pipe and a plurality of pressure relief holes, wherein the AB type double-component polyurethane grouting pipe is pre-embedded above the shield machine; the AB type double-component polyurethane grouting pipe is embedded after a hole is drilled on the ground above the soil bin of the shield machine at the receiving end to a position close to the soil bin of the shield machine; the WSS deep hole grouting pipe is drilled on the ground above the shield body of the shield machine at the receiving end to the position close to the shield body. The utility model discloses a structure can block the groundwater around the receiving end entrance to a cave fast, has avoided coordinating again and has consolidated, wait for the time limit for a project delay scheduling problem that reinforcement intensity leads to, shortens construction period widely.

Description

Processing structure for reinforcing failure of shield receiving end in high-pressure water-rich sand layer

Technical Field

The utility model belongs to shield structure construction field specifically is a shield constructs in high pressure rich water sand bed and receives end reinforcement inefficacy's processing structure.

Background

With the high-speed development of modern city construction, the trend that the large-area exploitation of underground space relieves the urban volume and traffic pressure is inevitable is, and the shield method is the best underground traffic construction method at present due to the fact that construction is rapid and the influence on the ground is small. In the shield subway construction, a shield machine enters an excavated tunnel from a receiving hole and then performs tunneling construction, after the construction of a tunnel in a certain section is completed, the surrounding soil body is kept stable, meanwhile, the shield machine enters a shield receiving hole along a designed route, and after the shield machine receives the surrounding soil body, the shield process of the stage is completed. In the shield construction, the normal tunneling process of the shield is relatively safe, the risk points of the normal tunneling process are mainly concentrated in the receiving and receiving stages of the shield, and the shield receiving and receiving belong to key nodes in the shield construction process.

The shield construction process is carried out in an underground soil layer, and the reinforcing quality of the shield receiving part is poor, so that water and sand gushing at a tunnel portal are easy to occur, and the normal receiving of the shield is directly influenced. At present, in foreign countries, if the cement base end cannot be reinforced due to geological conditions or ground conditions, a horizontal freezing reinforcement method is often adopted, but the shield still has a great risk of reaching and receiving due to the length limitation of a reinforcement body and the excessive abundance of underground water. The existing tunnel portal sealing mechanism mainly comprises an annular curtain cloth rubber plate, an annular pressing plate and a hinge plate, wherein the annular curtain cloth rubber plate is fixed on the outdoor annular outer side wall of a receiving tunnel portal of an excavated tunnel, the inner diameter of the annular curtain cloth rubber plate is smaller than the diameter of the tunnel portal, the annular pressing plate is buckled and pressed on the outer ring of the annular curtain cloth rubber plate, and the hinge plate is uniformly distributed on the outer side surface of the annular pressing plate along the circular arc of the outer circle. However, in the actual use process of the conventional sealing device of the cord fabric, the ring plate and the folding plate, the water gushing at the hole opening cannot be completely sealed because the cord fabric rubber and the shield shell cannot be completely and tightly sealed, and the slurry leakage phenomenon is inevitable even if the grouting is carried out at the hole door; when the water burst is large or the time is long, a major safety accident is easily caused. Particularly, in a high-water-pressure water-rich sandy stratum, if water gushing and sand gushing occur during shield receiving, disastrous results can be caused, and particularly under the conditions of unsatisfactory end reinforcing effect and underground water development, the shield receiving difficulty degree and risk are multiplied geometrically. Therefore, when the end reinforcement is not ideal and even fails, how to ensure the safe receiving of the shield machine is a difficult problem which needs to be solved urgently.

Disclosure of Invention

The utility model discloses problem to prior art exists provides a shield constructs among high pressure rich water sand bed and receives end reinforcement inefficacy's processing structure, and this structure can block the groundwater around the receiving end portal fast, has avoided coordinating again to consolidate, has waited for the time limit for a project delay scheduling problem that the reinforcement intensity leads to, shortens construction period widely.

In order to achieve the technical purpose, the technical scheme provided by the utility model is that the shield receiving end reinforcement failure processing structure in the high-pressure water-rich sand layer is constructed before the shield machine reaches the continuous wall close to the tunnel portal and the continuous wall of the tunnel portal is broken, and the processing structure specifically comprises an AB type double-component polyurethane grouting pipe, a WSS deep hole grouting pipe and a plurality of pressure relief holes arranged on the side wall of the tunnel portal, wherein the AB type double-component polyurethane grouting pipe is pre-embedded above the shield machine; the AB type double-component polyurethane grouting pipe is embedded after a hole is drilled on the ground above the soil bin of the shield machine at the receiving end to a position close to the soil bin of the shield machine; the WSS deep hole grouting pipe is drilled on the ground above the shield body of the shield machine at the receiving end to the position close to the shield body.

The utility model discloses better technical scheme: the AB type double-component polyurethane grouting pipe embedded drilling hole is formed in the position, corresponding to the point positions of 2, 10, 3 and 9, above the soil bin of the shield tunneling machine through a double-pipe drilling machine, the distance from the drilling position to the tunnel portal continuous wall is 2.5-3.5 m, each hole is drilled to the position 8-12 cm away from the soil bin of the shield tunneling machine, two pipelines of the AB type double-component polyurethane grouting pipe are vertically embedded in each drilling hole, and the two pipelines are all embedded to the bottom of the drilling hole.

The utility model discloses better technical scheme: the WSS deep hole grouting pipe embedding drill hole is formed in positions corresponding to 2, 10, 3 and 9 point positions above a soil bin of the shield tunneling machine by a double-pipe drilling machine, the distance from the embedding drill hole to a tunnel portal continuous wall is 1-1.5 m, and each hole is drilled to a position 8-12 cm away from a shield body of the shield tunneling machine; before the WSS deep-hole grouting pipe is adopted to inject the double-slurry, inert slurry is filled in the soil bin of the shield tunneling machine.

The utility model discloses better technical scheme the pressure release hole is equipped with four, arranges the shield respectively in and receives on the lateral wall of 5 position, 6 position, 7 positions, 12 positions of portal.

The utility model discloses better technical scheme: and the ground end of the AB type double-component polyurethane grouting pipe is respectively connected with two gear pumps.

The utility model has the advantages that:

(1) the utility model adopts deep hole conduit grouting before the tunnel portal is broken, firstly adopts the pre-buried pipeline deep hole grouting AB type double-component polyurethane, blocks the water flow channel outside the cutter head soil bin of the shield machine, then fills the soil bin of the shield machine with inert slurry, then drills on the ground above the shield body of the receiving end shield machine, and uses the double-liquid grouting machine to perform double-liquid blocking on the water flow channel around the shield body; the combination of the two types of grouting can not only be used for grouting the slurry for WSS deep hole grouting into the soil bin, but also prevent the shield body from being wrapped by double-slurry, and can achieve a better grouting reinforcement effect;

(2) before the shield receiving, the utility model adopts the rear side to perform vertical grouting, high-performance high-quality polyurethane is injected into radial holes of the shield and the shield tail in the shield machine to block water sources around the shield body, high-performance high-quality polyurethane is injected behind the duct piece, and a water stop hoop is made for double liquid slurry to block the water source behind the shield tail;

(3) a dewatering well and an observation well are arranged in the range of the waterproof curtain at the receiving end, when the shield machine arrives, the dewatering well is used for dewatering the end head all the time, a pressure relief hole is drilled in the side wall of the tunnel door to drain a water source of a gap between the diaphragm wall and a station main body maintenance structure, the water level at the end head is ensured to be below the bottom of the tunnel, so that the soil body collapse caused by the overhigh underground water level in the arrival process is prevented, and a better dewatering effect is achieved.

Drawings

FIG. 1 is a schematic view of the distribution of grout pipes;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a cross-sectional view taken along line B-B of FIG. 1;

fig. 4 is a schematic view of the distribution of the pressure relief holes.

In the figure: the method comprises the following steps of 1-shield tunneling machine, 2-tunnel portal continuous wall, 3-AB type double-component polyurethane grouting pipe, 4-WSS deep hole grouting pipe, 5-pressure relief hole, 6-shield receiving tunnel portal and 7-tunnel portal side wall.

Detailed Description

The present invention will be further explained with reference to the drawings and examples. Fig. 1 to 4 are drawings of the embodiment, which are drawn in a simplified manner and are only used for the purpose of clearly and concisely illustrating the embodiment of the present invention. The following detailed description of the embodiments of the present invention is presented in the drawings and is not intended to limit the scope of the invention as claimed. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "inner", "outer", "left", "right", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, or orientations or positional relationships that are conventionally placed when the products of the present invention are used, or orientations or positional relationships that are conventionally understood by those skilled in the art, and are merely for convenience of description of the present invention and simplifying the description, but do not indicate or imply that the device or element that is referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

The embodiment provides a processing structure for reinforcing failure of a shield receiving end in a high-pressure water-rich sand layer, as shown in fig. 1 to 4, the processing structure is constructed before a shield machine 1 reaches a continuous wall 2 close to a tunnel portal and the continuous wall 2 of the tunnel portal is broken, and the processing structure specifically comprises an AB type two-component polyurethane grouting pipe 3, a WSS deep hole grouting pipe 4 and a plurality of pressure relief holes 5, wherein the AB type two-component polyurethane grouting pipe 3 is pre-embedded above the shield machine 1; the AB type double-component polyurethane grouting pipe 3 is a grouting pipe which is buried after a hole is drilled on the ground above the soil bin of the shield machine 1 at the receiving end to a position close to the soil bin of the shield machine; the WSS deep hole grouting pipe 4 is drilled on the ground above the shield body of the receiving end shield machine 1 to a position close to the shield body. The AB type double-component polyurethane grouting pipe 3 is buried in the borehole and is drilled at the positions corresponding to the point positions of 2, 10, 3 and 9 points above the soil bin of the shield machine 1 by a double-pipe drilling machine, the distance from the drilling position to the tunnel portal continuous wall 2 is 2.5-3.5 m, each hole is drilled to the position 8-12 cm away from the soil bin of the shield machine, two pipelines of the AB type double-component polyurethane grouting pipe 3 are vertically buried in each drilled hole, and the two pipelines are buried to the bottom of the drilled hole. The WSS deep hole grouting pipe 4 is buried and drilled by a double-pipe drilling machine, holes are drilled at positions corresponding to the point positions of 2, 10, 3 and 9 above a soil bin of the shield tunneling machine 1, the distance from the buried drill holes to the tunnel portal continuous wall 2 is 1-1.5 m, and each hole is drilled to the position of 8-12 cm of a shield body of the shield tunneling machine; before the WSS deep-hole grouting pipe 4 is adopted to inject the double-slurry, inert slurry is filled in the soil bin of the shield tunneling machine. Four pressure relief holes 5 are arranged on the side walls of the shield receiving tunnel portal 6, which are respectively located at the 5-point position, the 6-point position, the 7-point position and the 12-point position. The ground end of the AB type double-component polyurethane grouting pipe 3 is respectively connected with two gear pumps.

The utility model is further explained below with reference to the following examples: the embodiment aims at a subway construction project, a shield receiving end of the construction project is diving and I bearing water, and the main stratum is silt and sand inclusion silt. Design and adoption of foundation reinforcement

The triaxial stirring stake is consolidated, and 250mm of overlap joint between the stake, and the reinforcement equipment ability satisfies the requirement of consolidating the degree of depth and consolidating the quality. The space of 300mm between the mixing pile and the underground wall is adopted

Reinforcing the triple-pipe high-pressure jet grouting piles, overlapping 300mm piles, and using the cement at 300 kg/m; 2 waterproof curtains are adopted at the joint of the waterproof curtain and the enclosure structure

The triple-pipe rotary jet pile is reinforced, the cement mixing amount is 250kg/m, and a precipitation well is arranged in the reinforced area for precipitation. Before the shield machine arrives between the Zhonghai region and the sea disc region, the core sample for the first cavity door coring is incomplete. And (4) after the hole door core sample is reinforced again by adopting methods such as high-pressure rotary spraying, hole door horizontal grouting and the like, the hole door core sample is qualified. However, when the cutter head of the shield machine reaches the receiving end diaphragm wall, a large amount of water gushes in the tunnel portal breaking period, and when the tunnel portal is broken in the middle sea area, the pressure of the soil bin is maintained at about 1bar for a long time, and the situation in the bin portal cannot be observed by opening the bin portal. Taking corresponding measure to carry out the drainage back to the soil storehouse and opening the storehouse and observe the interior water level of storehouse and change, the discovery is under the condition that all precipitation wells carried out precipitation operation, and soil storehouse water level 1h is internal can from bottom 5, 7 position rises to 2, 10 positions, also is similar condition when the inter-sea-disc shield constructs the receipt, takes place this type of phenomenon through the analysis because the shield constructs the end and consolidates the inefficacy, however, under the condition that the end reinforcing effect is not good and the end does not possess the increase precipitation well, for guaranteeing that two shield constructs quick-witted safe receipts, adopted the utility model discloses a and the processing structure handles the back, and the recombination portal sealing device receives, and its specific work progress is as follows:

(1) injecting AB type double-component polyurethane into the deep hole of the embedded pipeline: before the tunnel portal is broken, as shown in fig. 1 and 2, a grouting drilling machine is used for drilling holes at positions corresponding to point positions 2, 10, 3 and 9 above a soil bin of the shield tunneling machine on the ground 3m away from a ground connecting wall, and each hole is drilled to be 10cm away from a cutter head of the shield tunneling machine; after drilling, injecting the polyurethane of the component A by using a 1.1t gear pump and injecting the polyurethane of the component B by using a 5 t gear pump on the ground, and plugging a water flow channel outside a cutter head of the shield tunneling machine; two pipes for injecting AB type double-component polyurethane need to be pre-buried to the bottom of a drill hole, a check valve is respectively arranged on the ground of the two pipes, the two pipes are connected to the bottom of the underground drill hole in a junction pipeline, the length of the junction pipeline is 30cm, the AB type double-component polyurethane is prevented from being blocked by overlong injection of the AB type double-component polyurethane in the junction pipeline, the mixing ratio of the double-component polyurethane A to the double-component polyurethane B is 1:5, and the reaction time is 1 min.

(2) WSS deep hole grouting: before a tunnel portal is broken, filling inert slurry in a soil bin of the shield machine, then drilling holes at positions corresponding to point positions 2, 10, 3 and 9 above a shield body of the shield machine by a grouting drilling machine on the ground 1.2m away from a ground connecting wall as shown in a graph 1 and a graph 3, and drilling each hole to 10cm away from the shield body of the shield machine; before the hole door is broken, two slurry suction pipes of the double-fluid grouting pump are respectively placed into cement slurry and a water glass barrel, the cement slurry and the water glass barrel enter a hole through a double-fluid faucet at the upper part of a power head of a drilling machine, a double-channel main shaft, a double-layer drill rod, a hole bottom mixer and a drill bit, and double-fluid slurry is mixed at the hole bottom mixer; the initial setting time of the grout is less than 20s, and at the moment, the double-grout can form a sealing strip near the drill bit to prevent the grout from flowing back to the ground.

(3) High-performance and high-quality polyurethane is injected into radial holes of a shield and a shield tail in the shield machine before a tunnel portal is broken, so that the source of water in a soil bin is reduced, and the aim of controlling water flow and partial fracture water between a shield body and surrounding rocks is fulfilled; high-performance high-quality polyurethane is injected into radial holes of a shield and a shield tail in a shield machine, people are arranged to observe the water flow condition in a bin in soil, and high-performance high-quality polyurethane is injected into the radial holes corresponding to the convection water to block water sources around the shield body.

(4) 6 dewatering wells and 2 observation wells are arranged in the range of the waterproof curtain at the receiving end, and the ends are subjected to dewatering by using the dewatering wells all the time when the shield machine arrives; meanwhile, in order to ensure that the water level of the end head is below the bottom of the tunnel and prevent soil body collapse caused by overhigh underground water level in the process of arrival, pressure relief holes are formed in the side walls of the tunnel portal to drain water sources of the underground diaphragm wall and the gap of the station main body maintenance structure, and as the underground water pressure is high, pressure relief holes are formed in the side walls of the tunnel portal 5 and 7 and the side walls of the tunnel portal 6 and 12 to achieve a better precipitation effect, as shown in fig. 4.

(5) Before the shield machine arrives at a portal reinforcement body, portal breaking is carried out in advance, 9 observation holes are formed in a Chinese character 'mi' shape on a portal before the portal breaking, whether a water seepage phenomenon exists or not is observed, technical indexes such as self-stability and the like are achieved, all indexes meet the requirements of construction specifications, and then portal chiseling is carried out; the designed thickness of the diaphragm wall of the tunnel portal to be broken is 80cm, in order to prevent the instability of soil bodies after the tunnel portal is completely broken from endangering the safety of stations and tunnels, the thickness of 50cm is firstly broken in the process of breaking the tunnel portal, and the rest 30cm is broken after the tunnel portal is broken, so that the exposure time of the tunnel face of the tunnel portal is shortened.

(6) And finally, welding a water stop steel plate in the tunnel portal steel ring to seal the tunnel portal: specifically, 2 arc-shaped elastic steel plates with the thickness of 5mm and the height of 18cm are adopted, two complete circles are welded in the steel ring of the tunnel door at an interval of 10cm, the arc-shaped steel plates are slotted at an interval of 10cm, and the depth of the slot is 10 cm. And a high-density sponge strip of 180mm multiplied by 100mm is filled between the two circles of arc-shaped steel plates.

Practice proves that the method of the utility model is innovative and applied, and ensures that the shield is smoothly, safely and efficiently received.

To sum up, for the utility model discloses an embodiment of listing, nevertheless the utility model discloses not only be limited to above-mentioned embodiment, as long as reach with any same or similar means the technical effect of the utility model, all should belong to the scope of the protection of the utility model.

Claims (5)

1. The utility model provides a shield constructs in rich water sand bed of high pressure and receives end reinforcement processing structure that became invalid which characterized in that: the processing structure is constructed before the shield machine (1) reaches the continuous wall (2) close to the tunnel portal and the continuous wall (2) is broken, and specifically comprises an AB type two-component polyurethane grouting pipe (3) pre-embedded above the shield machine (1), a WSS deep hole grouting pipe (4) and a plurality of pressure relief holes (5) formed in the side wall of the tunnel portal; the AB type double-component polyurethane grouting pipe (3) is a grouting pipe which is buried after a hole is drilled on the ground above the soil bin of the shield machine (1) at the receiving end to a position close to the soil bin of the shield machine; the WSS deep hole grouting pipe (4) is drilled on the ground above the shield body of the receiving end shield machine (1) to the position close to the shield body; the plurality of pressure relief holes (5) are distributed on a tunnel portal side wall (7) around the shield receiving tunnel portal (6).

2. The structure of claim 1 for treating reinforcement failure of the shield receiving end in the high-pressure water-rich sand layer is characterized in that: the AB type double-component polyurethane grouting pipe (3) is buried and drilled, a double-pipe drilling machine is used for drilling at positions corresponding to point positions of 2, 10, 3 and 9 positions above a soil bin of a shield machine (1), the distance from the drilling position to a tunnel portal continuous wall (2) is 2.5-3.5 m, each hole is drilled to a position 8-12 cm away from the soil bin of the shield machine, two pipelines of the AB type double-component polyurethane grouting pipe (3) are vertically buried in each drilling hole, and the two pipelines are buried to the bottom of the drilling hole.

3. The structure of claim 1 for treating reinforcement failure of the shield receiving end in the high-pressure water-rich sand layer is characterized in that: the WSS deep hole grouting pipe (4) is buried and drilled by adopting a double-pipe drilling machine to drill holes at positions corresponding to point positions of 2, 10, 3 and 9 above a soil bin of the shield machine (1), the distance from the buried drill hole to a tunnel portal continuous wall (2) is 1-1.5 m, and each hole is drilled to a position of 8-12 cm of a shield body of the shield machine; before the WSS deep-hole grouting pipe (4) is adopted to inject the double-slurry, inert slurry is filled in the soil bin of the shield tunneling machine.

4. The structure of claim 1 for treating reinforcement failure of the shield receiving end in the high-pressure water-rich sand layer is characterized in that: four pressure relief holes (5) are arranged and are respectively arranged on the side walls of the shield receiving tunnel portal (6) at the 5-point position, the 6-point position, the 7-point position and the 12-point position.

5. The structure for treating the reinforcement failure of the shield receiving end in the high-pressure water-rich sand layer according to claim 2, characterized in that: the ground end of the AB type double-component polyurethane grouting pipe (3) is respectively connected with two gear pumps.

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