Treatment method for head water seepage of anti-floating anchor rod for crossing weak confined water stratum

Abstract

The invention provides a treatment method for head water seepage of an anti-floating anchor rod for penetrating through a weak confined water stratum. The method comprises the following steps: arranging a drainage ditch and a sump for drainage according to the seepage flow of the anti-floating anchor; positioning the periphery of the anti-floating anchor according to the length of the anti-floating anchor, and then drilling, grouting and lowering a grouting floral tube; the rubber fastening rings are sleeved on the floral tube at intervals so as to isolate water and increase friction force; and after the grouting pipe is lifted up, grouting is conducted on all the holes, and a seepage isolation body wrapping the anti-floating anchor rod body is formed. According to the anti-floating anchor rod, the problem that underground weak confined water seeps on the head of the anchor rod along a gap between the anchor rod body and a surrounding soil body after the anti-floating anchor rod is constructed can be effectively solved, underground water is isolated, and extra pulling resistance is provided; the defects that when the water leakage amount of underground water is slightly large, an anti-floating anchor rod water stop steel plate cannot stop water completely and effectively, and the pulling resistance of the anchor rod is slightly insufficient are overcome, normal construction of a cushion layer and water prevention in the later period and safety of a raft plate are guaranteed, and the treatment method is efficient, low in cost and high in maneuverability.

Description

Technical Field

[0001] The invention relates to an anti-floating anchor rod project in the field of construction projects in weakly confined water areas, and in particular to a method for treating water seepage at the head of an anti-floating anchor rod used for penetrating weakly confined water strata. Background Art

[0002] The soil in nature is an inhomogeneous bulk material with many pores in it, and groundwater is stored in these pores. When the aquifer is covered by a weakly permeable layer, the groundwater in the aquifer has a certain pressure-bearing capacity. If the overlying weakly permeable layer has through cracks due to construction or other reasons, the groundwater in the aquifer will seep upward through the cracks to the ground.

[0003] When constructing anti-floating anchors, mechanical drilling and vibration may cause tiny and through cracks in the weakly permeable layer, or because the anti-floating anchor filling is not dense, groundwater may seep out of the ground through the through cracks or the contact points between the anti-floating anchor body and the soil, causing water accumulation on the ground and making it impossible to complete the next construction process. At the same time, the action of water flow reduces the pull-out resistance of the anti-floating anchor, which has an adverse effect on the quality of the project.

[0004] At present, the common treatment method for water seepage at the head of the anti-floating anchor is to bury a water-stopping steel plate in the raft to prevent water from seeping out of the raft, or to use chemical solvents such as water glass for blocking. Among them, the method of using a water-stopping steel plate only solves the water seepage of the raft, but cannot meet the working surface requirements of the cushion construction that will be carried out immediately after the anti-floating anchor construction is completed; and the water glass method is more expensive and has a greater pollution to the geological environment. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly pressurized water strata. This method can not only solve the problem of water seepage at the head of the anti-floating anchor rod, but also strengthen the pull-out resistance of the anti-floating anchor rod.

[0006] In order to solve the above technical problems, the present invention provides a method for treating water seepage at the head of an anti-floating anchor rod for penetrating a weakly confined water formation, and the specific steps are as follows:

[0007] S1. After the construction of the anti-floating anchor rod is completed, inspect and observe whether there is water seepage or slight water leakage at the pile head of the constructed anti-floating anchor rod, and keep a record of the anti-floating anchor rods that are seeping or leaking;

[0008] S2. Dig drainage ditches and water collection pits around the anti-floating anchors where water seepage and bubbling occurs, and direct the seepage water through the drainage ditches into the water collection pits for pumping and drainage;

[0009] S3. With the center of the anti-floating anchor as the center, 3 to 5 holes with a diameter of 40 to 60 mm are arranged on the circumference of a circular area with a radius of 40 to 50 cm, and the depth of the holes is not less than 0.5 m of the length of the anti-floating anchor;

[0010] S4. In the drilled holes constructed in step S3, grouting flower tubes with a diameter of 25 to 32 mm are respectively lowered to the bottom of the holes, each grouting flower tube protrudes 0.4 to 0.6 m from the ground, and a rubber fastening ring is sleeved on the flower tube every 3 to 5 m. The outer surface of the rubber fastening ring is provided with threads and barbs. Before grouting, the grouting flower tube is slightly lifted up so that the threads and barbs of the rubber fastening ring are close to the hole wall, and then cement slurry with a water-cement ratio of 1:0.5 to 1:1 is injected into the hole until the grouting emerges and lasts for 1 to 2 minutes;

[0011] S5. After the treatment in step S4 is completed, observe whether the anti-floating anchor rod is leaking after the treatment. If there is no more water seepage, the water seepage treatment of the head of the anti-floating anchor rod is completed, and the water seepage treatment of the head of the next anti-floating anchor rod can be carried out; if there is still water seepage, repeat steps S3 and S4, arrange the drilling holes again and continue grouting until the water seepage completely disappears, and the drilling holes arranged again are arranged at intervals with the drilling holes arranged previously;

[0012] S6. After all the processing is completed, pour the base plate concrete, and during the pouring, cast the grouting pipe and the base plate as one.

[0013] A better technical solution of the present invention: the drainage ditch in the S2 step is excavated to a depth of 3 to 5 cm, and the sump is dug into a cube with a side length of 20 cm to 30 cm; the drainage ditch is excavated from the anchor rod seepage position, and a slope of 3% to 4% is set to drain the seepage water to the sump, and the water is pumped out after the sump is full.

[0014] A better technical solution of the present invention: in the step S3, 3 to 5 boreholes are evenly distributed along the circumference of a circular area with a radius of 40 to 50 cm and the center of the anti-floating anchor as the center, the diameter of each borehole is 50 mm, and the center of the borehole is 40 cm away from the center of the anti-floating anchor.

[0015] A better technical solution of the present invention: the diameter of the grouting flower tube in the S4 step is 32 mm; the length of the rubber fastening ring is 25 to 35 cm, the thread distribution length is 18 cm to 23 cm, and the root length is 8 to 12 cm; the thread on the outside of the rubber fastening ring is serrated, the top and side surfaces of the thread are flat, and the bottom surface is an inclined surface and is inclined upward; the barbs on the outside of the rubber fastening ring are integrated with the topmost layer of thread, and the barbs protrude upward.

[0016] A preferred technical solution of the present invention: the slurry in step S4 is pure cement slurry; the water-cement ratio of the cement slurry is 1:0.5; if it is found that the grouting hole is not full after the grouting is completed, secondary grouting should be performed until the grouting hole is completely filled.

[0017] A better technical solution of the present invention is as follows: in the S3 step, three grouting holes are provided, and the angle between the three grouting holes is 120°; in the S5 step, if the anti-floating anchor rod is still leaking, three new grouting holes are arranged between the original three grouting holes, and the angle between the six grouting holes is 60°, and grouting is continued through the three newly added grouting holes until the water seepage disappears completely.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0019] (1) The present invention can eliminate the influence of water seepage by drainage and grouting before the construction of the building raft, which not only provides a good working surface for subsequent construction, but also adds additional water-stopping protection for the water-stopping steel plate in the raft;

[0020] (2) The present invention uses a grouting pipe to pressurize cement slurry into soil cracks and the interface between the anti-floating anchor rod and the soil layer, thereby closing the groundwater infiltration channel and completely eliminating the possibility of water seepage problems;

[0021] (3) The present invention arranges rubber fastening rings in sections on the grouting flower pipe, and isolates groundwater in sections by lifting and grouting during the construction process, further preventing the occurrence of water seepage problems; at the same time, the grouting pipe and the base plate are cast as one, and the friction with the surrounding pipe wall is increased by the threads and protrusions on the rubber fastening ring, which indirectly improves the pull-out resistance of the treated anti-floating anchor rod and improves the safety of the project.

[0022] The present invention provides a relatively detailed set of implementation steps and methods for treating water seepage at the head of an anti-floating anchor rod passing through a weakly pressurized water stratum, which not only solves the problem of water seepage at the head of the anti-floating anchor rod, but also can reinforce the pull-out resistance of the anti-floating anchor rod. This treatment method is low in cost and convenient in construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a side view schematic diagram of the arrangement of the grouting pipe in the present invention;

[0024] Figure 2 It is a plan view of the arrangement of the grouting pipe, drainage ditch and sump in the embodiment of the present invention;

[0025] Figure 3 is a front view of the rubber fastening ring of the present invention;

[0026] Figure 4 is a top view of the rubber fastening ring of the present invention;

[0027] Figure 5 This is a schematic diagram of the effect after grouting.

[0028] In the figure: 1- anti-floating anchor rod; 2- weakly permeable layer; 3- aquifer; 4- through cracks in the soil; 5- grouting hole; 6- grouting pipe; 7- rubber fastening ring; 8- water seepage at the head of the anti-floating anchor rod; 9- drainage ditch; 10- sump; 11- grouting body. DETAILED DESCRIPTION

[0029] In order to make the purpose and technical solution of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment 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] The equipment used in the embodiment includes a drilling rig, a grouting pump, and a water pump; the drilling rig is used to construct a grouting hole 5, and the grouting pump injects cement slurry into the grouting hole 5 through a grouting pipe 6 to form a columnar consolidation body around the grouting hole 5; when the three grouting holes 5 around the anti-floating anchor 1 are all grouted, a continuous impermeable grouting body 11 can be formed around the anti-floating anchor 1.

[0031] The specific construction steps of the method for treating water seepage at the head of an anti-floating anchor rod passing through a weakly confined water formation in the embodiment are as follows:

[0032] S1. Check whether there are signs of water seepage 8 at the pile heads of the constructed anti-floating anchor rods 1, and keep records of the anti-floating anchor rods 1 that have water seepage 8; specifically, check each one on site against the drawings, and record the anti-floating anchor rods 1 that have water seepage 8 according to the drawing numbers.

[0033] S2. According to the amount of water seepage of the anti-floating anchor 1 to be treated, Figure 3 As shown, dig a drainage ditch 9 and a sump 10, and introduce the seepage water 8 at the head of the anti-floating anchor rod 1 into the sump 10 through the drainage ditch 9. The size and depth of the sump 10 are based on the needs of on-site construction. After the sump 10 is full of water, it is pumped out and drained in time. Since the amount of seepage is generally not large in this case, the diversion drainage ditch can be excavated to a depth of 3 to 5 cm, and the sump can be excavated as a cube with a side length of 20 cm. The main purpose of the drainage ditch 9 and the sump 10 is to pump out the accumulated water on the basement floor to facilitate the construction of the next process; the drainage ditch 9 is excavated from the anchor rod seepage part, and a 3% slope can be set to drain the seepage water to the sump. When the water volume in the sump reaches a certain level, it can be centrally pumped out to the site drainage system.

[0034] S3. With the center of the anti-floating anchor 1 to be treated as the center of the circle, three 50mm diameter holes 5 are evenly arranged on the circumference at a radius of 40cm. The length of the holes 5 should not be less than 0.5m of the length of the anti-floating anchor 1. Figure 1As shown, the included angle of the three grouting holes is 120°.

[0035] S4. In each borehole 5 constructed in step S3, a grouting tube 6 with a diameter of 32 mm is lowered to the bottom of the hole. The grouting tube 6 extends 0.5 m above the ground, which can facilitate the grouting to be slightly lifted up in the later grouting; a rubber fastening ring 7 is put on the grouting tube 6 every 3 to 5 meters, and the grouting tube 6 is slightly lifted up before grouting so that the threads and thorns of the rubber fastening ring 7 are close to the hole wall, which increases the friction and also plays a role of segmented water isolation; then, cement slurry with a water-cement ratio of 1:0.5 is injected into the hole until the slurry emerges and lasts for 1 to 2 minutes; after the slurry is initially set, the borehole 5 that is not filled with cement slurry is grouted for the second time until the slurry completely fills the borehole 5 and a continuous grouting body 11 is formed around the anti-floating anchor rod 1, such as Figure 5 In the embodiment, the inner side of the rubber fastening ring 7 is sleeved on the outer wall of the grouting flower tube, and the specific structure of the rubber fastening ring 7 is as follows: Figure 3 and Figure 4 As shown, the rubber fastening ring 7 is similar to a cylindrical structure, the rubber fastening ring is 30 cm long, the thread distribution length is 20 cm, and the root length is 10 cm; its outer surface is provided with multiple layers of threads and barbs, and the outer side surface is provided with threads and barbs to increase friction, and at the same time can play a water-proof role; the threads on the outside of the rubber fastening ring 7 are serrated, the top and side surfaces of the threads are flat, and the bottom surface is an inclined surface and is inclined upward. This design can increase the upward friction of the rubber fastening ring, as a reinforcement measure for the pull-out resistance of the anti-floating anchor; barbs are provided on the outside of the uppermost thread, and the barbs can be integrated with the uppermost thread, and the barbs protrude upward. When the rubber fastening ring receives buoyancy and tends to move upward, the friction can be increased, as a reinforcement measure for the pull-out resistance of the anti-floating anchor.

[0036] S5. Observe whether the anti-floating anchor rod 1 is leaking after treatment. If there is no more water seepage, the anti-floating anchor rod 1 has been treated and the next water seepage anchor rod can be treated. If there is still water seepage, three additional boreholes 5 are added between the three original boreholes 5 around the anti-floating anchor rod 1 to continue grouting until the water seepage completely disappears. The three newly added grouting holes are arranged at intervals between the original three grouting holes. After the arrangement, the angle between the six grouting holes is 60°, and grouting is continued through the three newly added grouting holes until the water seepage completely disappears.

[0037] S6. After all the processing was completed, the base plate concrete was constructed. When pouring the base plate, the grouting pipe and the base plate were poured as one.

[0038] The above description is only used to illustrate the preferred specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly confined water formations, characterized in that: The specific steps are as follows: S1. After the construction of the anti-floating anchor rod is completed, inspect and observe whether there is water seepage or slight water leakage at the pile head of the constructed anti-floating anchor rod, and keep a record of the anti-floating anchor rods that are seeping or leaking; S2. Dig drainage ditches and water collection pits around the anti-floating anchors where water seepage and bubbling occurs, and direct the seepage water through the drainage ditches into the water collection pits for pumping and drainage; S3. With the center of the anti-floating anchor as the center, 3 to 5 holes with a diameter of 40 to 60 mm are arranged on the circumference of a circular area with a radius of 40 to 50 cm, and the depth of the holes is not less than 0.5 m of the length of the anti-floating anchor; S4. In the drilled holes constructed in step S3, grouting flower tubes with a diameter of 25 to 32 mm are respectively lowered to the bottom of the holes, each grouting flower tube protrudes 0.4 to 0.6 m from the ground, and a rubber fastening ring is sleeved on the flower tube every 3 to 5 m. The outer surface of the rubber fastening ring is provided with threads and barbs. Before grouting, the grouting flower tube is slightly lifted up so that the threads and barbs of the rubber fastening ring are close to the hole wall, and then cement slurry with a water-cement ratio of 1:0.5 to 1:1 is injected into the hole until the grouting emerges and lasts for 1 to 2 minutes; S5. After the treatment in step S4 is completed, observe whether the anti-floating anchor rod is leaking after the treatment. If there is no more water seepage, the water seepage treatment of the head of the anti-floating anchor rod is completed, and the water seepage treatment of the head of the next anti-floating anchor rod can be carried out; if there is still water seepage, repeat steps S3 and S4, arrange the drilling holes again and continue grouting until the water seepage completely disappears, and the drilling holes arranged again are arranged at intervals with the drilling holes arranged previously; S6. After all the processing is completed, pour the base plate concrete, and during the pouring, cast the grouting pipe and the base plate as one.

2. A method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly confined water formation according to claim 1, characterized in that: The drainage ditch in step S2 is excavated to a depth of 3 to 5 cm, and the sump is dug into a cube with a side length of 20 to 30 cm; the drainage ditch is excavated from the anchor rod seepage position, and a slope of 3% to 4% is set to drain the seepage water to the sump, and the water is pumped out after the sump is full.

3. A method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly confined water formation according to claim 1, characterized in that: In the step S3, 3 to 5 boreholes are evenly distributed along the circumference of a circular area with a radius of 40 to 50 cm and a center of the anti-floating anchor. The diameter of each borehole is 50 mm, and the center of the borehole is 40 cm away from the center of the anti-floating anchor.

4. A method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly confined water formation according to claim 1, characterized in that: The diameter of the grouting flower tube in step S4 is 32mm; the length of the rubber fastening ring is 25-35cm, the thread distribution length is 18cm-23cm, and the root length is 8-12cm; the thread on the outside of the rubber fastening ring is serrated, the top and side surfaces of the thread are flat, and the bottom surface is an inclined surface and is inclined upward; the barbs on the outside of the rubber fastening ring are integrated with the topmost layer of thread, and the barbs protrude upward.

5. A method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly confined water formation according to claim 1, characterized in that: The slurry in step S4 is pure cement slurry; the water-cement ratio of the cement slurry is 1:0.5; if it is found that the grouting hole is not filled after the grouting is completed, secondary grouting should be carried out until the grouting hole is completely filled.

6. The method for treating water seepage at the head of an anti-floating anchor rod for penetrating weakly confined water formation according to claim 1, characterized in that: In step S3, three grouting holes are provided, and the angle between the three grouting holes is 120°; in step S5, if the anti-floating anchor rod still leaks water, three new grouting holes are arranged between the original three grouting holes, and the angle between the six grouting holes is 60°, and grouting is continued through the three newly added grouting holes until the water seepage disappears completely.

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