Treatment method for relatively concentrated water gushing of underground engineering

Abstract

The invention discloses a method for treating relatively concentrated gushing water in underground engineering, which comprises the following specific steps of: draining water in the underground engineering to expose a water outlet point; cleaning an underground engineering base; finishing a water outlet and detecting the extension direction of a water outlet channel; water is collected and guided by adopting a pipeline; the water guide pipeline is lengthened; the underground space is submerged; the tail end of the aqueduct is lifted out of water; and the water guide pipeline is used for grouting and pumping and draining accumulated water in the underground space. The core of the method is that after water guiding and collecting are conducted on a water outlet point through the water guiding pipeline, the underground space is submerged by water discharged from the underground engineering, so that when grouting treatment is conducted through the water guiding pipeline, the grouting pressure can be counteracted to a certain extent by means of water accumulated in the underground space, and the grouting effect is improved. The effect of grouting pressure on the interior of a rock stratum near a water outlet point is relatively reduced, effective diffusion of grout is guaranteed, meanwhile, damage to a base rock stratum can be prevented, and the treatment safety and effect are guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of groundwater treatment methods, and in particular to a method for treating relatively concentrated water gushing in underground projects. Background Art

[0002] When excavating deep foundation pits, tunnels, lanes, shafts, and basements, when encountering water-rich rock layers, if detection and treatment are not timely, sudden water inrush accidents may occur, which may cause direct flooding of underground space, or long-term strong drainage will cause a large amount of power waste and economic losses. For example, in a deep foundation pit under construction on Line 4 of Xuzhou Metro in Jiangsu Province, the water output of the limestone base reaches 1500m 3 / h, with a daily drainage of 36,000m 3 The daily drainage cost reached 36,000 yuan.

[0003] At present, there are generally the following ways to deal with large amounts of water gushing caused by the accidental exposure of water-bearing bodies in underground projects. One is to bury grouting pipes directly in the outlets and channels. After the grouting pipes are solidified, grouting and plugging are performed directly through the grouting pipes. This method is suitable for water discharge from rock formations with low water pressure, regular water outlets, and high rock strength and stability. For working conditions with relatively low rock strength, once the grouting pipes are closed before grouting, as the water pressure at the water outlet rises, the grouting pipes may be directly loosened or even pulled out, and the rock formation may be damaged, resulting in new water outlets. The second is a method for plugging high-pressure and high-flow water inrush in mines, as described in a Chinese patent application with application number 2019108697755. The method disclosed in the law is to construct drainage holes on the water outlet channel first, and then grouting and plugging the water outlet when the water is drained. This method requires a clear grasp of the grouting channel to achieve; third, if the Chinese patent static water cement grouting pad construction method with application number 2010106164844; the Chinese patent inclined well underwater grouting pad construction method with application number 2015104209843 is disclosed, the underground project is flooded, and a certain thickness of concrete water stop pad is poured underwater. After the grouting pad is fully solidified, the accumulated water is pumped out, and then grouting and water stopping operations are performed on the grouting pad. This method is mainly suitable for underground projects with small bases. And the cast grouting pad often needs to be thicker. After the grouting pad achieves the effect, the water outlet needs to be plugged in the later stage. Summary of the invention

[0004] In view of the above-mentioned technical deficiencies, the purpose of the present invention is to provide a method for controlling relatively concentrated water gushing in underground projects, which fully considers the characteristics of water outlet points, geological and hydrogeological conditions, and is mainly suitable for the control of water gushing points in underground projects with relatively concentrated water outlet points, weak rock strata, large underground project base, and relatively shallow burial. It has the characteristics of simple principle, safety, reliability, and easy operation.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for treating relatively concentrated water inrush in underground engineering, comprising the following steps:

[0007] S1. Drainage of underground projects to expose water outlets: Use the drainage system to continuously pump out the accumulated water and gushing water in underground projects to fully expose the water outlets at the base;

[0008] S2. Cleaning the base of underground engineering: During the continuous pumping of accumulated water and gushing water to the base, personnel and machinery enter the base of underground engineering to clean the water outlets, clear the surrounding gravel and debris, and fully expose all water outlets, so that the location, water volume, water outlet form and outlet shape of all water outlets can be observed;

[0009] S3. Adjustment of the water outlet and detection of the extension direction of the water outlet channel: Use a pneumatic pick, hammer, or steel chisel to properly adjust the water outlet, and use a steel bar or wooden stick to detect the extension direction of the water outlet channel from the water outlet inward;

[0010] S4. Use pipes to collect and guide water: embed a water-guiding pipe with a certain depth and certain deformability and strength for guiding and accumulating water from the water outlet. The outer diameter of the water-guiding pipe should match the water outlet as much as possible. Then, the gap between the water-guiding pipe and the water outlet should be effectively filled to ensure that the gap does not leak. The water is completely concentrated in the water-guiding pipe and flows out. This step needs to complete the water-guiding treatment of all water outlets.

[0011] S5. Connecting water pipes: Connecting water pipes, the length of which is greater than the buried depth of the underground engineering base and greater than the height of the water level of the water source, and connecting the tail ends of all water pipes to the suspension ropes;

[0012] S6. Flooding the underground space: Stop draining the underground project and use the water from the underground project to gradually flood the underground space until the water level is completely stable;

[0013] S7, lifting the tail section of the water pipe out of the water: using the suspension rope to lift the water pipe out of the water;

[0014] S8. Grouting using the water conduit: The water conduit is connected to the grouting pipeline for grouting, and the slurry enters the water conduit channel through the water conduit, thereby blocking the water outlet and the water conduit channel;

[0015] S9. Pumping out water from underground spaces: After the slurry has fully solidified, pump out all the water from underground spaces, cut off the water pipes, and complete the sealing of water gushing points in underground projects.

[0016] Preferably, in step S1, the actual drainage capacity of the drainage system must be greater than the water flow of the underground project, and the head must be greater than the burial depth of the underground project.

[0017] Preferably, in step S2, when the water outlet is corrected, it is corrected to a relatively regular shape, such as an approximately circular or elliptical shape, as much as possible.

[0018] Preferably, in steps S4-S7, the water conduit is always in an open state.

[0019] Preferably, in step S4, cotton yarn or woven bags stained with flocculation slurry are used to effectively fill the gap between the water conduit and the water outlet.

[0020] Preferably, in step S4, the flocculation slurry is cement-water glass two-liquid slurry or two-component urea-formaldehyde resin slurry.

[0021] Preferably, in step S8, ordinary cement slurry is preferably used for grouting. If the grouting amount is too large, water glass can be appropriately added to replace the slurry with cement-water glass double liquid slurry, or directly replace the slurry with chemical slurry.

[0022] The beneficial effects of the present invention are:

[0023] The core of the present invention is to use water pipes to guide and collect water at the water outlet point, and then use the water outlet of the underground project itself to flood the underground space. In this way, when using the water pipes for grouting treatment, the water accumulation in the underground space itself can be used to offset the grouting pressure to a certain extent, and the effect of the grouting pressure on the rock formation near the water outlet point can be relatively reduced. While ensuring the effective diffusion of the slurry, the damage to the basement rock formation can be prevented to ensure the safety and effectiveness of the treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic diagram of a water point exposed after drainage of an underground project provided by an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of connecting water pipes provided in an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of grouting a water guide pipeline provided by an embodiment of the present invention;

[0028] Figure 4 A schematic diagram of the underground space after water is pumped out according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] 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.

[0030] This embodiment provides a method for treating relatively concentrated water inrush in underground projects. The specific steps are as follows: ① Drain the underground project and expose the water outlet point. Figure 1 →② Cleaning the base of underground engineering →③ Repairing the water outlet and detecting the extension direction of the water outlet channel →④ Using pipes to collect and guide water →⑤ Connecting the water guide pipe (see the installation of the water guide pipe for details) Figure 2 )→⑥Flood the underground space→⑦The tail end of the water pipe is raised to the surface→⑧Use the water pipe for grouting (see Figure 3 ) → ⑨ Pump out water from underground space (see Figure 4 ).

[0031] Take the shield machine receiving and sending foundation pit at the intersection of Metro Line 4 in a certain city as an example. The depth is 30m, the length and width are both 40m, the upper 10m is a loose layer, and the lower 20m is a limestone layer. The limestone layer is highly water-rich and has developed cracks. When the foundation pit is constructed to a depth of 30m, the base rock structure is poor, and three main water gushing points are exposed. They are all wide cracks, approximately elliptical, with a total water gushing flow of 1500m 3 / h, with a daily drainage of 36,000m 3 The daily drainage cost reached 36,000 yuan.

[0032] First, on the basis of pumping out the water gushing and accumulating in the foundation pit, personnel and machinery entered the base, surveyed the water outlet, and corrected the water outlet. The correction was mainly done with a pneumatic pick, and the outlet was corrected into an approximate circle. Steel bars were inserted into the water outlet to explore the extension direction of the water outlet channel. It was found that the extension directions of the water outlet channels were different, but overall they were relatively regular and the channels were unobstructed.

[0033] A thick-walled corrugated pipe that basically matches the diameter of the water outlet is used as the water guide pipe. Corrugated pipes of corresponding diameters of 2.1m, 1.5m, and 1.4m are placed at the three water outlets respectively. The gap between the corrugated pipe and the water outlet is densely filled with discarded cement woven bags soaked in cement-water glass double liquid slurry, and the filling depth exceeds 1.0m. Then the length of the connected corrugated pipe reaches 40m, and the tail of the corrugated pipe is connected to the ground with a steel wire rope.

[0034] After stopping the drainage of the foundation pit for about 50 hours, the water level in the foundation pit was basically stable, and the depth of the water reached 25m. The end of the bellows was lifted out of the water using a steel wire rope connected to the tail of the bellows and fixed at the edge of the foundation pit. The grouting pump was connected to the bellows pipeline, and grouting was performed on each bellows one by one (see Figure 3, grouting in the water pipe), initially inject single-liquid cement slurry, the grouting volume minus the volume of slurry in the corrugated pipe, the cement slurry consumption at a single water point reaches 15m 3 , then add about 5% of the volume of water glass to the cement slurry, but the water point has grouting up to 10m 3 After that, grouting is stopped, and it is predicted that the length of the water outlet channel blocked by the slurry exceeds 20m;

[0035] See also Figure 4 48 hours after the grouting was completed, when the slurry was fully solidified, the accumulated water in the foundation pit was drained and no water was found at the bottom of the well. The water-conducting bellows were cut off, and the treatment of multiple relatively concentrated water gushings at the bottom of the foundation pit was completed.

[0036] The present invention uses a water pipe to guide and collect water at the water outlet point, and then uses the water outlet of the underground project itself to flood the underground space. In this way, when using the water pipe for grouting treatment, the water accumulation in the underground space itself can offset the grouting pressure to a certain extent, and relatively reduce the effect of the grouting pressure on the rock formation near the water outlet point. While ensuring the effective diffusion of the slurry, the damage to the basement rock formation can be prevented, so as to ensure the safety and effect of the treatment.

[0037] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for treating relatively concentrated water inrush in underground engineering, characterized in that: The following steps are involved: S1. Drainage of underground projects to expose water outlets: Use the drainage system to continuously pump out the accumulated water and gushing water in underground projects to fully expose the water outlets at the base; S2. Cleaning the base of underground projects: After the accumulated water and gushing water are continuously pumped to the base, the water outlet points of the base of underground projects are cleaned, and all water outlet points are completely exposed, so that the location, water volume, water outlet form and shape of all water outlet points can be observed; S3. Water outlet trimming and water outlet channel extension direction detection: Make appropriate corrections to the water outlet and detect the extension direction of the water outlet channel from the water outlet inward; S4. Use pipes to collect and guide water: insert a water-guiding pipe of a certain depth for guiding and accumulating water from the water outlet, and try to match the outer diameter of the water-guiding pipe with the water outlet. Then, effectively fill the gap between the water-guiding pipe and the water outlet to ensure that the gap does not leak. The water is completely concentrated in the water-guiding pipe and flows out. This step needs to complete the water-guiding treatment of all water outlets; S5. Connecting water pipes: Connecting water pipes, the length of which is greater than the buried depth of the underground engineering base and greater than the height of the water level of the water source, and connecting the tail ends of all water pipes to the suspension ropes; S6. Flooding the underground space: Stop draining the underground project and use the water from the underground project to gradually flood the underground space until the water level is completely stable; S7, lifting the tail section of the water pipe out of the water: using the suspension rope to lift the water pipe out of the water; S8. Grouting using the water conduit: The water conduit is connected to the grouting pipeline for grouting, and the slurry enters the water conduit channel through the water conduit, thereby blocking the water outlet and the water conduit channel; S9. Pumping out water from underground spaces: After the slurry has fully solidified, pump out all the water from underground spaces, cut off the water pipes, and complete the sealing of water gushing points in underground projects.

2. A method for treating relatively concentrated water inrush in underground engineering as claimed in claim 1, characterized in that: In step S1, the actual drainage capacity of the drainage system must be greater than the water flow of the underground project, and the head must be greater than the burial depth of the underground project.

3. A method for treating relatively concentrated water inrush in underground engineering as claimed in claim 1, characterized in that: In step S2, when the water outlet is corrected, it is corrected to a relatively regular shape as much as possible, such as an approximately circular or elliptical shape.

4. A method for treating relatively concentrated water inrush in underground engineering as claimed in claim 1, characterized in that: In steps S4-S7, the water conduit is always in an open state.

5. A method for treating relatively concentrated water inrush in underground engineering as claimed in claim 1, characterized in that: In step S4, cotton yarn or woven bags stained with flocculation slurry are used to effectively fill the gap between the water conduit and the water outlet.

6. A method for treating relatively concentrated water inrush in underground engineering as claimed in claim 5, characterized in that: In step S4, the flocculation slurry is cement-water glass two-liquid slurry or two-component urea-formaldehyde resin slurry.

7. A method for treating relatively concentrated water inrush in underground engineering as claimed in claim 1, characterized in that: In step S8, ordinary cement slurry is preferably used for grouting. If the grouting amount is too large, water glass can be appropriately added to replace the cement-water glass double liquid slurry, or directly replace the chemical slurry.

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