A method for sealing leakage of underground engineering hole

Abstract

The application discloses a kind of underground engineering hole leakage plugging method, hole partition net and grouting pipe, method includes steps: S1: the hole of leakage is divided into multiple sub-holes;S2: grouting is formed to water-stop curtain to hole interior.The application can quickly plug hole leakage.

Description

Technical Field

[0001] This invention belongs to the field of underground engineering leakage control, and more specifically, relates to a method for sealing leakage in underground engineering cavities, a cavity separation net, and a grouting pipe. Background Technology

[0002] In underground engineering construction, such as cast-in-place concrete structures, precast masonry reinforcement in shield tunneling, and solid masonry structures, water leakage at the joints of concrete walls is a common problem. According to Article 4.2.12, Paragraph 2 of the "Technical Specification for Leakage Control in Underground Engineering" (JGJ / T 212-2010), leakage control measures should be determined based on the amount of leakage. When the leakage is small, it is usually considered as crack leakage and treated using crack sealing methods. However, when the leakage is large, the water pressure is high, and there is a possibility of water inrush, sand inrush, mud inrush, or other hazards that could endanger structural safety, it cannot be considered crack leakage, and crack sealing methods are not feasible. In such cases, on-site emergency repairs are necessary. Typically, the leaking area within the underground engineering should first be backfilled with soil or sandbags, and then a quick-setting cement-water glass grouting material should be injected onto the outside of the pit joint to form a water-stop curtain.

[0003] When a dangerous situation occurs on-site, a rapid response is required, and shortening the rescue time is crucial to eliminating the hazard. However, it takes considerable time to mobilize qualified basic treatment agencies, at least 12 hours, for them to arrive. Furthermore, the location of the curtain grouting for water stoppage on the outside remains uncertain, leading to a prolonged time to form the water-stopping curtain and severely impacting the rescue progress. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a method for rapidly sealing leaks in underground engineering cavities, a cavity partition mesh, and a grouting pipe.

[0005] The present invention adopts the following technical solution.

[0006] A method for sealing leakage in underground engineering cavities includes the following steps:

[0007] S1: Divide the leaking hole into multiple sub-holes;

[0008] S2: Grout is injected into the hole to form a water-stopping curtain.

[0009] Furthermore, in step S1, a perforated mesh is used to divide the leaking hole into multiple sub-holes. The perforated mesh includes multiple radial support rods and multiple connecting lines. One end of the multiple radial support rods is connected to each other, and each connecting line is connected to multiple radial support rods. The connection point of each connecting line and multiple radial support rods is located on the same circumference.

[0010] Furthermore, in step S2, the depth of grout injection into the hole is not less than L, where L = Kvt gK is an empirical coefficient; v is the flow velocity of fluid seeping through the hole; t g is the initial setting time of the sealing material; L is the distance between the grouting point and the hole.

[0011] Furthermore, before dividing the leaking hole into multiple sub-holes, the steps include: determining the size of the leaking hole, and if the diameter or width of the hole is greater than 100 mm, then performing steps S1-S2.

[0012] Furthermore, in step S2, the grouting materials include: polyurethane grouting materials, acrylate grouting materials, epoxy resin grouting materials, and cement-based grouting materials.

[0013] Furthermore, in step S2, grout is injected into the hole through a grouting pipe, the grouting pipe comprising: a pipe body, one end of which is provided with an air hole for introducing gas, and the other end of which is provided with a grouting hole, the pipe body also being provided with an openable injection hole for injecting grout; and a grouting piston, which is slidably disposed in the pipe body.

[0014] A spring, located in the tube and connected to the grouting piston, is used to drive the grouting piston to reset.

[0015] Injecting grout into the cavity to form a water-stop curtain includes:

[0016] S21: Insert the grouting pipe into the leaking hole;

[0017] S22: Air port connected to high-pressure air source;

[0018] S23: Inject grout into the pipe body through the injection hole, and then close the injection hole;

[0019] S24: Gas is injected through a high-pressure gas source. The gas pushes the grouting piston to move and squeezes the grout out of the grouting hole. Then the gas is also discharged through the grouting hole. After the gas pressure decreases, the grouting piston is pulled back to its original position by a spring.

[0020] S25: Repeat steps S23-S24 until the sealing is complete;

[0021] S26: Reduce the pressure of the gas injected from the high-pressure gas source, pull out the grouting pipe, and continue grouting through the grouting hole while pulling out the grouting pipe until the grouting pipe is completely pulled out.

[0022] Furthermore, after step S21, the procedure includes the step of backfilling the leaking area with soil or sandbags within the underground works; after step S25, the procedure includes the step of gradually removing the soil or sandbags backfilled at the leaking area.

[0023] This invention also provides a cavity separator mesh for use in sealing leaks in underground engineering cavities, comprising:

[0024] The umbrella-shaped partition net includes: multiple radial support rods and multiple connecting lines. The multiple radial support rods are connected at one end, and each connecting line is connected to multiple radial support rods. The connection points of each connecting line and multiple radial support rods are located on the same circumference. The radial support rods are made of steel, and the circumferential connecting lines are made of high-density polyethylene.

[0025] The driving mechanism includes: a shaft, a support ring, and multiple support rods; multiple radial support rods are rotatably connected to the shaft, the support ring is slidably sleeved on the shaft, and the multiple support rods are rotatably connected to the support ring and a corresponding radial support rod, respectively. The support ring slides along the shaft and can drive the multiple radial support rods to open or close through the multiple support rods; the driving mechanism also includes a holding spring and a pressing lock. The holding spring is sleeved on the shaft and fixed to the top end of the shaft and the support ring, so as to elastically drive the support ring to move away from the top end of the shaft; the pressing lock is fixed to the bottom end of the shaft to resist the movement of the support ring away from the top end of the shaft.

[0026] The present invention also provides a grouting pipe for use in a method of sealing leaks in underground engineering cavities, comprising:

[0027] The pipe body has an air hole at one end for introducing gas and a grouting hole at the other end. The pipe body also has an openable grouting hole for injecting grout.

[0028] The grouting piston is slidably disposed in the pipe body;

[0029] A spring, located in the tube and connected to the grouting piston, is used to drive the grouting piston to reset.

[0030] After gas is introduced into the vent, it pushes the grouting piston to move so that the grout inside the pipe is sprayed out from the grouting hole.

[0031] Beneficial effects

[0032] Compared with existing emergency rescue technologies, this invention has the following characteristics:

[0033] 1) Existing emergency rescue techniques use geological drilling rigs and require a series of procedures such as drilling holes and grouting, which necessitates a long preparation time, with the geological drilling rig typically taking at least 12 hours to arrive on site. In contrast, this invention involves construction directly near the leaking hole, and the high-pressure equipment used can be easily found on-site, such as nitrogen cylinders, oxygen cylinders, and acetylene cylinders, resulting in a much shorter preparation time.

[0034] 2) When a geological drilling rig completes a series of processes such as drilling and grouting, it requires a construction space to accommodate the rig and drill rod. However, this invention allows for construction directly near the leaking hole, requiring only the storage space for high-pressure equipment, resulting in a significantly smaller construction space.

[0035] 3) When geological drilling rigs perform a series of processes such as drilling and grouting, they may encounter difficulties such as quicksand causing borehole collapse and soft soil causing borehole shrinkage. Therefore, they need to be equipped with experienced technicians and three workers. However, this invention can be carried out directly near the leaking hole without the need for professional personnel. The on-site technical management personnel can direct and organize the workers to complete the construction directly.

[0036] 4) When geological drilling rigs drill and grout underground, they may encounter problems such as quicksand collapse and hole shrinkage in soft soil. There may also be pressurized water and gas pipelines near the surface, thus posing significant construction risks. This invention requires less technical skill from the workers involved, and the emergency equipment can be easily found on-site, greatly facilitating the organization of underground engineering emergency response personnel, saving time, improving the timeliness of emergency response, and correspondingly reducing the affected area of ​​seepage from the boreholes and significantly decreasing the risk of damage from seepage. Attached Figure Description

[0037] Figure 1 This is a front view of the perforated mesh according to an embodiment of the present invention.

[0038] Figure 2 for Figure 1 The side view of the perforated mesh shown.

[0039] Figure 3 for Figure 1 The perforated mesh shown is a side view in its retracted state.

[0040] Figure 4 This is a side view of the grouting pipe according to an embodiment of the present invention.

[0041] Figure 5 for Figure 4 The side view shows the grouting pipe in use.

[0042] Figure 6 for Figure 4 The side view shows another usage state of the grouting pipe.

[0043] Figure 7 This is a schematic diagram of the installation of the perforated mesh according to an embodiment of the present invention.

[0044] Figure 8 This is a schematic diagram of the installation of the grouting pipe according to an embodiment of the present invention.

[0045] Figure 9 This is a schematic diagram of sandbag stacking for leak sealing according to an embodiment of the present invention.

[0046] Figure 10 This is a schematic diagram illustrating the grouting effect according to an embodiment of the present invention.

[0047] In the diagram: 1-Radial support rod; 3-Connecting line; 4-Shaft rod; 5-Support rod; 6-Supporting spring; 7-Supporting ring; 8-Injection hole; 9-Pneumatic impact chamber; 10-Spring; 11-Injection piston; 12-Slurry chamber; 13-Injection hole; 14-Press lock. Detailed Implementation

[0048] The present invention will now be further described with reference to specific embodiments and accompanying drawings.

[0049] Please see Figure 1-10 This invention provides a method for sealing leaks in underground engineering cavities, comprising the following steps:

[0050] S1: Divide the leaking hole into multiple sub-holes;

[0051] S2: Grout is injected into the hole to form a water-stopping curtain.

[0052] This invention provides a method for sealing leaking holes in underground engineering, applicable to conditions with large leakage volumes and clearly visible leaking holes. Dividing the leaking hole into multiple sub-holes essentially does not change the leakage flow rate; this minimizes the pressure and difficulty of installing the separating mesh. The grouting target of the hole curtain is to form a large-particle water-stopping curtain on the outside of the leaking hole, thereby reducing the leakage volume.

[0053] Furthermore, in step S1, a perforated mesh is used to divide the leaking hole into multiple sub-holes. The perforated mesh includes multiple radial support rods 1 and multiple connecting lines 3. The multiple radial support rods 1 are connected at one end, and each connecting line 3 is connected to multiple radial support rods 1 respectively. The connection point of each connecting line 3 and multiple radial support rods 1 is located on the same circumference.

[0054] Radial support rod 1 and circumferential connecting line 3 together form a grid. The length and width of the grid shall not exceed 100mm. Radial support rod 1 should be made of umbrella-grade steel wire; circumferential connecting line 3 and grid nodes can be made and fixed using high-density polyethylene (HDPE); the length of radial support rod 1 should be greater than the hole size.

[0055] Furthermore, in step S2, the depth of grout injection into the hole is not less than L, where L = Kvt g ,:K is an empirical coefficient, usually taken as 10; v is the flow velocity of fluid seeping through the hole, m / s; t g , is the initial setting time of the sealing material, in seconds; L is the distance between the grouting point and the hole, in meters.

[0056] Furthermore, before dividing the leaking hole into multiple sub-holes, the steps include: determining the size of the leaking hole, and if the diameter or width of the hole is greater than 100 mm, then performing steps S1-S2.

[0057] Furthermore, in step S2, the grouting materials include: polyurethane grouting materials, acrylate grouting materials, epoxy resin grouting materials, and cement-based grouting materials.

[0058] Furthermore, in step S2, grout is injected into the hole through a grouting pipe, the grouting pipe comprising: a pipe body, one end of which is provided with an air hole for introducing gas, and the other end of which is provided with a grouting hole, the pipe body also being provided with an openable injection hole for injecting grout; and a grouting piston, which is slidably disposed in the pipe body.

[0059] A spring, located in the tube and connected to the grouting piston, is used to drive the grouting piston to reset.

[0060] Injecting grout into the cavity to form a water-stop curtain includes:

[0061] S21: Insert the grouting pipe into the leaking hole;

[0062] S22: Air port connected to high-pressure air source;

[0063] S23: Inject grout into the pipe body through the injection hole, and then close the injection hole;

[0064] S24: Gas is injected through a high-pressure gas source. The gas pushes the grouting piston to move and squeezes the grout out of the grouting hole. Then the gas is also discharged through the grouting hole. After the gas pressure decreases, the grouting piston is pulled back to its original position by a spring.

[0065] S25: Repeat steps S23-S24 until the sealing is complete, until there is no leakage in the pressure relief hole;

[0066] S26: Reduce the pressure of the gas injected from the high-pressure gas source, pull out the grouting pipe, and continue grouting in the grouting hole while pulling out the grouting pipe until the grouting pipe is completely pulled out, until the hole no longer leaks.

[0067] like Figure 8 Because the upper part of the seepage area is prone to leakage due to collapse, while the lower soil material is less likely to leak out but can be piled up; thus gradually achieving the effect of sealing the leak.

[0068] Furthermore, after step S21, the procedure includes the step of backfilling the leaking area with soil or sandbags within the underground works; after step S25, the procedure includes the step of gradually removing the soil or sandbags backfilled at the leaking area.

[0069] The purpose is to apply back pressure to the leakage point by backfilling with soil or sandbags, thereby quickly reducing the leakage.

[0070] The grouting pipe forms an angle α with the axial direction of the hole. The angle α should be as small as possible to reduce leakage of the grout.

[0071] This invention also provides a cavity separator mesh for use in sealing leaks in underground engineering cavities, comprising:

[0072] The umbrella-shaped partition net includes: multiple radial support rods 1 and multiple connecting lines 3. The multiple radial support rods 1 are connected at one end, and each connecting line 3 is connected to multiple radial support rods 1 respectively. The connection point of each connecting line 3 and multiple radial support rods 1 is located on the same circumference. The radial support rods 1 are made of steel. The circumferential connecting lines 3 are made of high-density polyethylene.

[0073] The driving mechanism includes: a shaft 4, a support ring 7, and multiple support rods 5; multiple radial support rods 1 are rotatably connected to the shaft 4, the support ring 7 is slidably sleeved on the shaft 4, and multiple support rods 5 are rotatably connected to the support ring 7 and a corresponding radial support rod 1, respectively. The support ring 7 can slide along the shaft 4 and drive the multiple radial support rods 1 to open or close through the multiple support rods 5.

[0074] Furthermore,

[0075] The driving mechanism further includes a supporting spring 6 and a pressing lock 14. The supporting spring 6 is sleeved on the shaft 4 and fixed to the top end of the shaft 4 and the support ring 7, so as to elastically drive the support ring 7 to move away from the top end of the shaft 4. The pressing lock 14 is fixed to the bottom end of the shaft to resist the movement of the support ring away from the top end of the shaft. Please refer to [link to relevant documentation]. Figure 7 Preferably, the shaft 4 has a detachable structure for easy installation. Specifically, the main body of the shaft 4 can be detached from its top. The top of the shaft 4 is connected to an umbrella-shaped partition net.

[0076] The present invention also provides a grouting pipe for use in a method of sealing leaks in underground engineering cavities, comprising:

[0077] The pipe body has an air hole at one end for introducing gas and a grouting hole 13 at the other end. The pipe body also has an openable grouting hole 8 for injecting grout.

[0078] The grouting piston 11 is slidably disposed in the pipe body;

[0079] A spring 10 is disposed in the tube and connected to the grouting piston 11 for driving the grouting piston 11 to reset;

[0080] After gas is introduced into the vent, it pushes the grouting piston to move so that the grout in the pipe is sprayed out from the grouting hole 13.

[0081] The grouting piston divides the pipe body into a pneumatic impact chamber 9 and a grout chamber 12. After gas is introduced into the pneumatic impact chamber 9 through the air hole, it pushes the grouting piston 11 to move, causing the grout in the grout chamber 12 to be squeezed out through the grouting hole 13. Then, gas is also squeezed out through the grouting hole 13, reducing the gas pressure received by the grouting piston 11. The spring 10 can then pull the grouting piston 11 back to its original position.

[0082] Please refer to Table 1, which contains sample data for the grouting fluid material.

[0083] Under standard test conditions, weigh (20±0.1) g of the sample into a 250 ml beaker using a balance, add 100 ml of water, record the time of water addition, and then quickly stir until homogeneous (about 10 s) before allowing it to stand, resulting in a white emulsion. The viscosity change is then continuously monitored using a glass rod. When the glass rod leaves the liquid surface and a string-like phenomenon occurs, the sample is considered to have gelled. The gelation time t is the time from the start of mixing the sample with water until the gel-like phenomenon occurs when the glass rod leaves the liquid surface. a .

[0084] Under standard test conditions, weigh (15±0.1) g of the sample into a 500 ml beaker, add 150 ml of water, stir quickly and evenly, and then let stand. When the sample and water in the beaker have fully reacted and no water can be poured out, the sample is considered to have completely solidified into a gel. Record the solidification time tb from the addition of water to the complete solidification of the gel.

[0085] Table 1. Effect of TDI content on the performance of waterborne polyurethane sealant

[0086] Operating conditions 1 2 3 4 5 6 <![CDATA[Setting time t a (s)]]> 35 40 54 76 70 66 <![CDATA[Solidification time t b (s)]]> 76 80 105 120 108 91

[0087] When polyurethane grouting material is mixed with water, it expands and foams to form a gel block after 35 to 75 seconds, which can then be used for leak sealing in underground engineering.

[0088] Formula L=Kvt g The usage method is as follows:

[0089] Based on the gel time of polyurethane grouting materials, which is approximately 35–76 seconds as shown in Table 1, and taking gravel leakage as an example, with a permeability coefficient of 0.05 cm / s, the calculation is performed according to the formula.

[0090] L = Kvt g =10*0.05*(35~76)=17.5~38.0(cm)

[0091] Therefore, the sealing depth can be calculated to be 17.5–38.0 cm.

Claims

1. A method for sealing leakage in underground engineering voids, characterized in that, Including the following steps: S1: Divide the leaking hole into multiple sub-holes; S2: Grout is injected into the hole to form a water-stopping curtain; In step S1, a perforated mesh is used to divide the leaking hole into multiple sub-holes. The perforated mesh includes multiple radial support rods and multiple connecting lines. One end of the multiple radial support rods is connected to each other, and each connecting line is connected to multiple radial support rods. The connection point of each connecting line and multiple radial support rods is located on the same circumference. In step S2, the depth of grouting into the hole is not less than L, where L = Kvtg, K is an empirical coefficient; v is the flow velocity of fluid leakage at the hole; tg is the initial setting time of the sealing material; and L is the distance between the grouting point and the hole.

2. The method for sealing leakage in underground engineering cavities according to claim 1, characterized in that, Before dividing the leaking hole into multiple sub-holes, the steps include: determining the size of the leaking hole, and if the diameter or width of the hole is greater than 100 mm, then performing steps S1-S2.

3. The method for sealing leakage in underground engineering cavities according to claim 1, characterized in that, In step S2, the grouting materials include: polyurethane grouting material, acrylate grouting material, epoxy resin grouting material, and cement-based grouting material.

4. The method for sealing leakage in underground engineering cavities according to claim 1, characterized in that, In step S2, grout is injected into the hole through a grouting pipe. The grouting pipe includes a pipe body, one end of which is provided with an air hole for introducing gas, and the other end of which is provided with a grouting hole. The pipe body is also provided with an openable injection hole for injecting grout. The grouting piston is slidably disposed in the pipe body; A spring, located in the tube and connected to the grouting piston, is used to drive the grouting piston to reset. Injecting grout into the cavity to form a water-stop curtain includes: S21: Insert the grouting pipe into the leaking hole; S22: Air port connected to high-pressure air source; S23: Inject grout into the pipe body through the injection hole, and then close the injection hole; S24: Gas is injected through a high-pressure gas source. The gas pushes the grouting piston to move and squeezes the grout out of the grouting hole. Then the gas is also discharged through the grouting hole. After the gas pressure decreases, the grouting piston is pulled back to its original position by a spring. S25: Repeat steps S23-S24 until the sealing is complete; S26: Reduce the pressure of the gas injected from the high-pressure gas source, pull out the grouting pipe, and continue grouting through the grouting hole while pulling out the grouting pipe until the grouting pipe is completely pulled out.

5. The method for sealing leakage in underground engineering cavities according to claim 4, characterized in that, The procedure following step S21 includes the step of backfilling the leaking area with soil or sandbags in the underground works; the procedure following step S25 includes the step of gradually removing the soil or sandbags backfilled at the leaking area.

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