Device for testing water blocking and dispersion resistance of slurry and method thereof

Abstract

A testing device and method for the water-blocking and anti-dispersion properties of grout are disclosed. The testing device includes: a main container, which contains a water storage space to simulate a groundwater environment and a grout space to contain the grout. The water storage space is located above and communicates with the grout space, and a first filter screen for water filtration is fixed at the bottom of the grout space. The top of the main container has an inlet for injecting grout and water into the container, and the bottom has an outlet. A water collection container is connected to the outlet. A pressurizing device is located outside the main container and is used to pressurize the container. A sealing cap is detachably connected to the inlet. This invention, by reserving a water storage space above the grout and injecting water into the storage space to simulate a groundwater environment, can accurately measure the anti-dispersion and water-blocking properties of the grout when exposed to groundwater during actual construction.

Description

Technical Field

[0001] This invention relates to the field of shield tunneling construction, specifically to a test device and test method for the water-blocking and anti-dispersion performance of slurry. Background Technology

[0002] Shield tunneling, as one of the main and commonly used construction methods for tunneling, boasts advantages such as high safety factor, fast working speed, high degree of automation, minimal impact on the surrounding environment, and strong adaptability. During the excavation of a slurry balance shield tunneling machine, if the gaps between the shield shell and the soil are not filled in a timely and dense manner, or if the filling material is prone to dispersion and lacks a barrier effect, slurry will flow backward, leading to tail leakage and segment floating. Therefore, simultaneous grouting is necessary within the gaps. To ensure the water-blocking and anti-dispersion properties of the injected grout, grout testing is required. Existing testing techniques utilize traditional filtration meters to measure the amount of water lost through the grout filter under certain pressure and time. This primarily measures the filtration loss of the grout itself. However, existing devices simulate the pressure environment by directly applying air pressure, which is not the actual water pressure environment during construction. This ignores the influence of groundwater on the grout and therefore cannot simulate the structural stability and anti-dispersion performance of the grout under groundwater pressure during actual construction, nor can it measure the water-blocking performance of the grout. Summary of the Invention

[0003] This invention provides a test device and method for testing the water-blocking and anti-dispersion properties of grout. By reserving a water storage space above the grout and injecting water into the storage space to simulate the groundwater environment, the anti-dispersion and water-blocking properties of the grout when it encounters groundwater during actual construction can be accurately measured.

[0004] A further improvement of the present invention is that it includes: a main container, wherein a water storage space for simulating a groundwater environment and a slurry space for containing slurry are formed inside the main container, the water storage space is located above the slurry space and communicates with the slurry space, and a first filter screen for water filtration is fixed at the bottom of the slurry space, the top of the main container is provided with a slurry inlet for injecting slurry and water into the main container, and the bottom of the main container is provided with a water outlet;

[0005] A water collection container, which is connected to the water outlet;

[0006] A pressurizing device is located outside the main container and is used to pressurize the main container. A sealing cap is detachably connected to the slurry inlet. The pressurizing end of the pressurizing device is detachably connected to the sealing cap and communicates with the interior of the main container through the sealing cap.

[0007] A further improvement of the present invention is that a second filter screen for further filtering the water filtered by the first filter screen is fixed inside the main container, below the first filter screen and above the water outlet, and the pore size of the second filter screen is smaller than that of the first filter screen.

[0008] A further improvement of the present invention is that the main body container is divided into a first section located at the top and a second section located at the bottom, the first section and the second section are detachably connected to form the main body container, the bottom of the first section is fitted over the top of the second section, and the edge of the first filter screen is attached to the top of the second section and abuts against the inner wall of the first section.

[0009] A further improvement of the present invention is that the outer periphery of the second segment is formed with a flange for supporting the bottom end of the first segment, and a sealing ring is fixed at the flange.

[0010] A further improvement of the present invention is that the slurry space is divided into an upper part of smaller size and a lower part of larger size that is connected to the upper part.

[0011] A further improvement of the present invention is that the inner wall of the main container, from below the first filter screen to the water outlet, gradually narrows inward to form a funnel shape.

[0012] The present invention discloses a test method for a slurry water-blocking and anti-dispersion performance testing device, comprising the following steps:

[0013] S1. Inject grout into the grout inlet until the grout space is filled, then stop grouting.

[0014] S2. Water is injected from the grout inlet to simulate a groundwater environment within the water storage space;

[0015] S3. Connect the pressurizing device to the grout inlet and apply air pressure to the main container. After reaching the preset value, turn off the pressurizing device and close the grout inlet to simulate soil pressure.

[0016] S4. Wait for a period of time. During the waiting period, some water in the slurry and water in the water storage space will flow into the water collection container from the outlet. After a period of time, measure the amount of water in the water collection container and judge the water blocking and anti-dispersion performance of the slurry based on the amount of water in the water collection container.

[0017] A further improvement of the present invention is that the time period mentioned in step S4 is 30 minutes to 2 hours.

[0018] A further improvement of the present invention is that, when injecting the slurry, the injected slurry is kept in close contact with the inner wall of the main container to prevent water in the water storage space from flowing downwards from the gap between the slurry and the inner wall of the main container during subsequent tests.

[0019] This invention provides a test device and method for testing the water-blocking and anti-dispersion properties of grout. By reserving a water storage space above the grout and injecting water into the storage space to simulate the groundwater environment, the anti-dispersion and water-blocking properties of the grout when it encounters groundwater during actual construction can be accurately measured. Attached Figure Description

[0020] Figure 1 Schematic diagram of the internal structure of the experimental device of this invention;

[0021] Figure 2 This is a schematic diagram of the external structure of the experimental device of the present invention;

[0022] Figure 3 This is a bottom view of the water outlet of the experimental device of the present invention;

[0023] 1. Main container; 11. First section; 12. Second section; 21. First filter screen; 22. Second filter screen; 3. Sealing cover; 4. Water outlet; 5. Slurry inlet; 6. Slurry space; 7. Water storage space; 8. Pressurization pipe; 9. Pressure gauge; 10. Sealing ring; 13. Internal thread; 14. External thread. Detailed Implementation

[0024] like Figure 1 As shown, the present invention provides a test device for the water-blocking and anti-dispersion performance of slurry, comprising: a main container 1, wherein a water storage space 7 for simulating a groundwater environment and a slurry space 6 for containing slurry are formed inside the main container 1, the water storage space 7 is located above the slurry space 6 and communicates with the slurry space 6, and a first filter screen 21 for water filtration is fixed at the bottom of the slurry space 6, the top of the main container 1 is provided with a slurry inlet for injecting slurry and water into the main container 1, and the bottom of the main container 1 is provided with a water outlet 4;

[0025] Water collection container, the water collection container is connected to the water outlet 4;

[0026] A pressurizing device is located outside the main container 1 and is used to pressurize the main container 1. A sealing cap 10 is connected to the slurry inlet 5 in an openable and closable manner. The pressurizing end of the pressurizing device is detachably connected to the sealing cap 3 and communicates with the interior of the main container 1 through the sealing cap 3.

[0027] In this embodiment, the water collection container is a graduated cylinder.

[0028] In the first embodiment, the main container 1 is divided into a first segment 11 located at the top and a second segment 12 located at the bottom. The first segment 11 and the second segment 12 are detachably connected to form the main container 1. The bottom of the first segment 11 is fitted over the top of the second segment 12. The edge of the first filter screen 21 is attached to the top of the second segment 12 and abuts against the inner wall of the first segment.

[0029] By dividing the main container 1 into two detachable sections and placing the first filter screen 21 on top of the second section 12, it is convenient to clean the first filter screen 21 after disassembling the main container 1, preventing solid particles in the slurry from clogging the first filter screen 21 and affecting subsequent tests, and facilitating reuse.

[0030] Better, such as Figure 1 As shown, in the first embodiment, the bottom inner wall of the first segment 11 is provided with an internal thread 13, and the outer wall of the second segment 12, which is sleeved on the bottom of the first segment 11, is provided with an external thread 14 that is adapted to the internal thread 13. The second segment 12 is connected to the first segment 11 by screwing the external thread 14 into the internal thread 13.

[0031] like Figure 1 As shown, the outer periphery of the second segment 12 has a flange for supporting the bottom end of the first segment 11, and a sealing ring 10 is fixed at the flange.

[0032] like Figure 1 , 2 As shown, in the second embodiment, at least one second filter screen 22 for further filtration is fixed inside the main container 1, below the first filter screen 21. The pore size of the second filter screen 22 is smaller than that of the first filter screen 21. By setting the second filter screen 22, the possibility of particles in the slurry passing through the filter screen and flowing out of the outlet 4 can be further reduced. In this embodiment, the pore size of the first filter screen 21 is slightly larger than that of the second filter screen 22, which can reduce the possibility of solid particles in the slurry clogging the first filter screen 21. In order to prevent some tiny solid particles in the slurry from passing through the first filter screen 21 and being discharged from the outlet 4, this embodiment sets a second filter screen 22 with a smaller pore size below the first filter screen 21 to intercept solid particles in the slurry that may pass through the first filter screen 21.

[0033] Better, such as Figure 2 As shown, in the second embodiment, the second segment 12 can be further divided into two detachable upper and lower segments, wherein the second filter screen 22 is fixed to the top of the lower segment so that the second filter screen 22 can also be cleaned after disassembly. The connection method between the upper and lower segments of the second segment 12 is the same as that between the first segment 11 and the second segment 12, and a sealing ring 10 is also provided at the corresponding position.

[0034] Better, such as Figure 1 , 2As shown, the slurry space is divided into a smaller upper part and a larger lower part connected to the upper part. By increasing the size of the lower part of the slurry space 6, the seepage path of water in the water storage space 7 is extended, further reducing the possibility of water in the water storage space 7 flowing downward along the gap between the slurry and the inner wall of the main container 1. Specifically, if water in the water storage space 7 flows downward from the gap between the slurry and the inner wall of the main container 1, this part of the water will be blocked by the slurry extending outward and will not continue to flow downward. By preventing water from flowing downward from the gap to the outlet 4, the error of the test is further reduced. In this embodiment, the inner diameter of the upper part is 150 mm and the inner diameter of the lower part is 180 mm.

[0035] like Figure 1 As shown, the inner wall of the main container 1 gradually narrows into a funnel shape from below the first filter screen 21 to the outlet 4. By setting the inner wall below the first filter screen 21 as a funnel, the possibility of water in the water storage space 7 flowing downward from the gap between the slurry and the inner wall of the main container 1 can be further reduced, thus reducing the error of the experiment.

[0036] In this embodiment, the bottom horn-shaped water outlet 4 is designed with an opening diameter of 30mm, a narrowing section diameter of 10mm, and a length of 50mm.

[0037] Better, such as Figure 2 As shown, the sealing cap 3 has an openable and closable pressurization hole, and a pressurization pipe 8 is detachably connected to the pressurization hole. In this embodiment, the pressurization device applies pressure to the main container 1 by applying air pressure. The pressurization device is connected to the main container 1 through the pressurization pipe 8, and a pressure gauge 9 is also installed on the pressurization pipe 8. By setting the pressure gauge 9, the pressure through the grouting pipe 8 can be detected when the pressurization device pressurizes the main container 1, so as to accurately apply pressure according to the specific scenario to be simulated in the experiment.

[0038] Preferably, in this embodiment, the main container 1 is 600mm high.

[0039] The present invention discloses a test method for a slurry water-blocking and anti-dispersion performance testing device, comprising the following steps:

[0040] S1. Inject grout into the grout inlet 5 until the grout space 6 is filled and then stop grouting;

[0041] S2. Water is injected from the slurry inlet 5 to simulate the groundwater environment in the water storage space 7;

[0042] S3. Connect the pressurizing device to the grout inlet 5 and apply air pressure to the main container 1. After reaching the preset value, turn off the pressurizing device and seal the grout inlet 5 to simulate soil pressure.

[0043] S4. Wait for a period of time. During the waiting period, some of the water in the slurry and the water in the water storage space 7 will flow into the water collection container from the outlet 4. After a period of time, measure the amount of water in the water collection container and judge the water blocking and anti-dispersion performance of the slurry based on the amount of water in the water collection container.

[0044] Preferably, in this embodiment, the main container 1 is a transparent container so that the injection process can be observed from the outside when the slurry and water are injected.

[0045] The time period in step S4 is 30 minutes to 2 hours. The waiting time can also be adjusted according to actual needs. In this embodiment, waiting for 30 minutes is sufficient.

[0046] Preferably, the pressurizing device in this embodiment can provide a maximum pressure of 2 MPa, but it can also be adjusted according to the actual situation.

[0047] Preferably, in this embodiment, the diameter of the grouting pipe 8 is 10 mm, and when water is injected through the grouting pipe 8, the flow rate ranges from 0.1 L / min to 2 L / min, and the maximum water injection volume in the water storage space 7 is 1 L.

[0048] Preferably, when injecting the grout, the injected grout should be kept in close contact with the inner wall of the main container 1 to prevent water in the water storage space 7 from flowing down through the gap between the grout and the inner wall of the main container 1 during subsequent tests, which would affect the accuracy of the test.

[0049] Ideally, after the test is completed, the equipment should be thoroughly cleaned in preparation for the next use. At the same time, the wear of the parts should be checked and worn parts should be replaced in a timely manner to ensure the long-term stability of the equipment.

[0050] The present invention has the following main advantages:

[0051] 1. This experimental setup can simulate a groundwater environment by injecting water and change the pressure acting on the grout by applying air pressure. This method can simulate the behavior of the grout under different pressure scenarios to observe changes in grout properties in a way that closely approximates actual construction conditions.

[0052] 2. By applying water pressure during the test, groundwater pressure is further simulated, providing a more realistic testing environment. This method can more comprehensively evaluate the water-blocking and anti-dispersion performance of the grout in actual construction.

[0053] 3. The special funnel shape and inclined pipe wall design of outlet 4 ensure a tight fit between the slurry and the sidewall, guaranteeing that the filtered water accurately reflects the water-blocking performance of the slurry during testing. This design effectively avoids errors during testing and improves the accuracy of test results.

[0054] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A test apparatus for the water-blocking and anti-dispersion properties of a slurry, characterized in that, include: The main container has a water storage space for simulating a groundwater environment and a slurry space for containing slurry. The water storage space is located above the slurry space and is connected to the slurry space. A first filter screen for water filtration is fixed at the bottom of the slurry space. The top of the main container has an inlet for injecting slurry and water into the main container, and the bottom of the main container has a water outlet. A water collection container, which is connected to the water outlet; A pressurizing device is located outside the main container and is used to pressurize the main container. A sealing cap is detachably connected to the slurry inlet. The pressurizing end of the pressurizing device is detachably connected to the sealing cap and communicates with the interior of the main container through the sealing cap.

2. The test apparatus for water-blocking and anti-dispersion properties of slurry as described in claim 1, characterized in that, Inside the main container, below the first filter screen and above the water outlet, there is a second filter screen for further filtering the water filtered by the first filter screen, and the pore size of the second filter screen is smaller than that of the first filter screen.

3. The test apparatus for water-blocking and anti-dispersion performance of slurry as described in claim 1, characterized in that, The main container is divided into a first section at the top and a second section at the bottom. The first section and the second section are detachably connected to form the main container. The bottom of the first section is fitted over the top of the second section, and the edge of the first filter screen is attached to the top of the second section and abuts against the inner wall of the first section.

4. The test apparatus for water-blocking and anti-dispersion performance of slurry as described in claim 3, characterized in that, The outer periphery of the second segment has a flange for supporting the bottom end of the first segment, and a sealing ring is fixed at the flange.

5. The test apparatus for water-blocking and anti-dispersion performance of slurry as described in claim 1, characterized in that, The slurry space is divided into a smaller upper part and a larger lower part that is connected to the upper part.

6. The test apparatus for water-blocking and anti-dispersion performance of slurry as described in claim 1, characterized in that, The inner wall of the main container gradually narrows inward from below the first filter screen to the water outlet, forming a funnel shape.

7. A test method for a test apparatus for the water-blocking and anti-dispersion properties of slurry as described in any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Inject grout into the grout inlet until the grout space is filled, then stop grouting. S2. Water is injected from the grout inlet to simulate a groundwater environment within the water storage space; S3. Connect the pressurizing device to the grout inlet and apply air pressure to the main container. After reaching the preset value, turn off the pressurizing device and close the grout inlet to simulate soil pressure. S4. Wait for a period of time. During the waiting period, some water in the slurry and water in the water storage space will flow into the water collection container from the outlet. After a period of time, measure the amount of water in the water collection container and judge the water blocking and anti-dispersion performance of the slurry based on the amount of water in the water collection container.

8. The test method of the slurry water-blocking and anti-dispersion performance test apparatus as described in claim 7, characterized in that, The time period mentioned in step S4 is 30 minutes to 2 hours.

9. The test method of the slurry water-blocking and anti-dispersion performance test apparatus as described in claim 7, characterized in that, When injecting the slurry, ensure that the injected slurry adheres tightly to the inner wall of the main container to prevent water in the water storage space from flowing downwards through the gap between the slurry and the inner wall of the main container during subsequent tests.

Images