A device for collecting lost particles in a coarse-grained soil anti-filtration protection test

Abstract

The present invention discloses a grading collection device for lost particles in a coarse-grained soil anti-filtration protection test, which is arranged below the coarse-grained soil anti-filtration protection test device and is used to collect lost protective soil during the anti-filtration protection test, so as to facilitate the determination of the change in the sample gradation in the protective soil through the corresponding full-sample particle size test, so as to judge the seepage characteristics of the protective soil during the anti-filtration test and the corresponding anti-filtration protection effect. A grading collection device for lost particles in a coarse-grained soil anti-filtration protection test comprises a collection box, the top port of the collection box has an assembly slot, a plurality of filter frames assembled in the assembly slots are sequentially arranged inside from bottom to top, the filter frames have a plurality of filter holes, the aperture of the filter holes on the filter frames increases from bottom to top, and there is a gap between two adjacent filter frames to form a collection chamber.

Description

Technical Field

[0001] The invention relates to the technical field of a coarse-grained soil anti-filtration protection test, and in particular to a grading collection device for lost particles in a coarse-grained soil anti-filtration protection test. Background Art

[0002] According to the "Standard for Geotechnical Test Methods" and "Test Procedures for Coarse-Grained Soil in Hydropower and Water Conservancy Projects", when conducting anti-filtration protection tests on coarse-grained soil, the migration of particles in the protective soil and the protected soil is an important basis for judging the anti-filtration effect. According to the requirements of the specifications, after the anti-filtration test, the particle size of fine particle loss in the protected soil should be recorded. At present, the corresponding test data can be determined by the full-sample particle size test of the protected soil after the test. However, due to the particle loss problem of the protective soil itself during the anti-filtration protection test, it is difficult to determine the change of the sample gradation in the protective soil through the corresponding full-sample particle size test to judge the seepage characteristics of the protective soil during the anti-filtration test and the corresponding anti-filtration protection effect. In addition, due to the particle loss problem during the test, the total amount of the protective soil and the protected soil before and after the test is not conserved, which interferes with the judgment of the test results. Therefore, it is necessary to set a grading collection device for lost particles at the downstream overflow to collect the sample particles lost with the infiltration water flow during the anti-filtration protection test. However, the current test-related specifications and procedures and corresponding test equipment do not provide corresponding lost particle collection devices. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a device for collecting lost particles in a coarse-grained soil anti-filtration protection test.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] A grading collection device for lost particles in a coarse-grained soil anti-filtration protection test is arranged below the coarse-grained soil anti-filtration protection test device, comprising a collection box, a top port of the collection box having an assembly slot, a plurality of filter frames assembled in the assembly slot are sequentially arranged inside the box from bottom to top, the filter frames having a plurality of filter holes, the filter holes on the filter frames increasing in diameter from bottom to top, a gap between two adjacent filter frames to form a collection chamber, each collection chamber being connected to a pressure reducing pipe extending out of the collection box, a drainage chamber being provided between the filter frame at the bottom and the collection box, and a drainage head being provided on the drainage chamber; the filter frame comprising a frame for being erected in the assembly slot, the upper and lower surfaces of the frame being paved with elastic layers, and when the coarse-grained soil anti-filtration protection test device is placed on the filter frame at the top, the elastic layer is in a compressed state. The multiple filter frames are arranged to form multiple collection chambers in the collection box that cooperate with the coarse-grained soil anti-filtration protection test device to collect the lost protective soil during the anti-filtration protection test, thereby facilitating the determination of the change in the sample grading in the protective soil through the corresponding full-sample particle size test, so as to judge the seepage characteristics of the protective soil and the corresponding anti-filtration protection effect during the anti-filtration test.

[0006] Preferably, assembly holes that match multiple pressure-reducing tubes one by one are opened on the wall of the collection box, and a pressure-reducing hole is opened on the filter frame. The pressure-reducing tube passes through the assembly hole and is screwed to the pressure-reducing hole, and a sealing sleeve is also provided at the position where the pressure-reducing tube contacts the assembly hole. The setting of the pressure-reducing tube is the key to reducing the influence of the weakened water permeability caused by the small-sized filter screen on the back filtration test results.

[0007] Preferably, a water seepage piece is provided at one end of the pressure reducing tube close to the filter frame to prevent the protective soil collected in the collecting chamber from entering the pressure reducing tube during the anti-filtration protection test. Specifically, the water seepage piece includes an assembly cylinder screwed to the pressure reducing tube, a plurality of water seepage holes are provided on the cylinder wall of the assembly cylinder, and a water seepage cloth is wrapped on the outside. The end away from the pressure reducing tube is a closed end and is provided with an outer cover to form a closed chamber, and a vibration motor is arranged in the closed chamber.

[0008] Preferably, a avoidance hole is provided on the filter frame with a low horizontal height for the pressure reducing pipe on the filter frame with a high horizontal height to pass through; a positioning block is provided on the assembly groove, and a positioning groove is provided on the frame. Whenever multiple filter frames are arranged in the assembly groove in sequence, the positioning groove and the positioning block are matched, and the avoidance hole and the assembly hole for the same pressure reducing pipe to pass through are in the same straight line, which is convenient for the installation of the filter frame.

[0009] Preferably, the bottom of the collection box has supporting legs, and the drainage head is located at the bottom of the collection box and has a length smaller than the length of the supporting legs.

[0010] Preferably, a collecting chamber is also formed between the filter frame located at the bottom and the bottom of the collecting box. A drain pipe is connected to the drain head. The drain pipe and the pressure reducing pipe are both "L" shaped and include a horizontal section and a vertical section. A water head measuring sensor is provided on the vertical section to determine whether blockage occurs in the collecting chamber corresponding to the drain pipe, thereby ensuring the accuracy of the test results.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] 1. The present invention forms multiple collection chambers that cooperate with the coarse-grained soil anti-filtration protection test device through multiple filter frames arranged in the collection box, collects the lost protective soil during the anti-filtration protection test, and then facilitates the determination of the change of the sample gradation in the protective soil through the corresponding full-sample particle size test, so as to judge the seepage characteristics of the protective soil during the anti-filtration test and the corresponding anti-filtration protection effect without affecting the head size of the anti-filtration test.

[0013] 2. Multiple filter frames of different numbers can realize the graded collection of lost protective soil, which can more intuitively determine the way in which the protective soil filters the protected soil and the location where penetration damage occurs.

[0014] 3. The elastic layer arranged on the filter frame realizes sealing between the filter frame, the collection box and the coarse-grained soil anti-filtration protection test device under the gravity of the coarse-grained soil anti-filtration protection test device, thereby avoiding loss of infiltration flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall assembly structure of the present invention;

[0016] Figure 2 It is a schematic diagram of the structure of the collection box of the present invention;

[0017] Figure 3 It is a structural schematic diagram of the filter frame of the present invention;

[0018] Figure 4 It is a schematic structural diagram of the water seepage member of the present invention.

[0019] Figure symbols: 1. Collecting box, 11. Assembly groove, 12. Drainage chamber, 13. Drainage head, 14. Assembly hole, 15. Positioning block, 16. Support leg, 17. Drainage pipe, 2. Filter frame, 21. Frame, 22. Elastic layer, 23. Pressure reducing hole, 24. Avoidance hole, 25. Positioning groove, 3. Collecting chamber, 4. Pressure reducing pipe, 41. Sealing sleeve, 5. Water seepage part, 51. Assembly cylinder, 52. Water seepage cloth, 53. Outer cover, 54. Sealed chamber, 55. Vibration motor, 6. Water head measurement sensor. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0021] Example

[0022] like Figure 1-3 The device for collecting lost particles in a coarse-grained soil anti-filtration protection test shown in the figure is arranged below the coarse-grained soil anti-filtration protection test device, and comprises a collecting box 1. The top port of the collecting box 1 has an assembly slot 11. A plurality of filter frames 2 assembled in the assembly slot 11 are arranged in sequence from bottom to top inside the collecting box 1. A gap is provided between two adjacent filter frames 2 to form a collecting chamber 3. The filter frame 2 has a plurality of filter holes. The apertures of the filter holes on the filter frame 2 increase from bottom to top, so that the plurality of collecting chambers 3 can realize the graded collection of lost protective soil, thereby facilitating the determination of the change in the sample gradation in the protective soil through the corresponding full-sample particle size test, so as to judge the seepage characteristics of the protective soil during the anti-filtration test. And the corresponding anti-filtration protection effect; each collecting chamber 3 is connected to a pressure reducing pipe 4 extending out of the collecting box 1, which is used to reduce the impact on the anti-filtration test results after the water permeability of the collecting chamber 3 is weakened due to the increase in the number of filter frames 2; a drainage chamber 12 is provided between the filter frame 2 at the bottom and the collecting box 1, and a drainage head 13 is provided on the drainage chamber 12; the filter frame 2 includes a frame 21 for being erected in the assembly groove 11, and the upper and lower surfaces of the frame 21 are paved with an elastic layer 22. When the coarse-grained soil anti-filtration protection test device is placed on the filter frame 2 at the top, the elastic layer 22 is in a compressed state, so that the filter frame 2, the collecting box 1 and the coarse-grained soil anti-filtration protection test device are sealed to avoid loss of infiltration flow.

[0023] The present invention forms multiple collection chambers 3 that cooperate with the coarse-grained soil filtration protection test device through multiple filter frames 2 arranged in the collection box 1, so as to collect the lost protective soil during the filtration protection test, thereby facilitating the determination of the change of the sample gradation in the protective soil through the corresponding full-sample particle size test, so as to judge the seepage characteristics of the protective soil during the filtration test and the corresponding filtration protection effect without affecting the head size of the filtration test.

[0024] In the coarse-grained soil backfiltration protection test, the particle size of the sample is generally between 0mm and 60mm. However, affected by the aperture size of the permeable plate in the backfiltration test, the particle size of the lost particles is basically concentrated below 5mm. Therefore, how to completely collect the lost particles between 0mm and 5mm in the test without affecting the water head in the backfiltration test is a technical problem that needs to be solved by this invention.

[0025] In the anti-filtration protection test, the number of filter frames 2 is set to 5. From top to bottom, the apertures of the filter holes on each filter frame 2 are 5mm, 2mm, 0.5mm, 0.25mm, and 0.1mm, respectively. Without affecting the head size in the anti-filtration test, multiple collection chambers 3 can realize the graded collection of lost particles between 0mm and 5mm, which can accurately support the judgment of the anti-filtration test results and provide an important basis for the analysis of subsequent test results. Especially for piping type soil, since the anti-filtration test only judges whether the anti-filtration protection effect can be achieved based on the i-v curve, it is difficult to judge whether the protective soil or the protected soil has undergone infiltration damage during the anti-filtration protection test. The graded collection of lost particles with the infiltration water flow can judge the source and particle group range of the lost objects based on the collected objects, and can more intuitively determine the anti-filtration protection mode of the protective soil on the protected soil and the location of the infiltration damage.

[0026] As a preferred solution of the above embodiment, the wall of the collecting box 1 is provided with assembly holes 14 which match with a plurality of pressure reducing pipes 4 one by one, and the filter frame 2 is provided with pressure reducing holes 23. The pressure reducing pipes 4 pass through the assembly holes 14 and are screwed with the pressure reducing holes 23, and the portion where the pressure reducing pipes 4 contact the assembly holes 14 is also provided with a sealing sleeve 41. The arrangement of the pressure reducing pipes 4 is used to reduce the insufficient downstream water flow capacity due to the smaller aperture of the filter holes on the small-sized filter frame 2, thereby causing the upstream water level to increase, and further causing the actual total water head borne by the sample to be lower than the measured test water head, thereby making the reverse filtration test results more accurate.

[0027] As a preferred solution of the above embodiment, Figure 4 As shown, a water seepage component 5 is provided at one end of the pressure reducing pipe 4 close to the filter frame 2 to prevent the protective soil collected in the collecting chamber 3 from entering the pressure reducing pipe 4 during the anti-filtration protection test. Specifically, the water seepage component 5 includes an assembly cylinder 51 screwed to the pressure reducing pipe 4, and a plurality of water seepage holes are provided on the cylinder wall of the assembly cylinder 51. The outer side is wrapped with a water seepage cloth 52. The end away from the pressure reducing pipe 4 is a closed end and is sleeved with an outer cover 53 to form a closed chamber 54. A vibration motor 55 is arranged in the closed chamber 54.

[0028] In the above scheme, if Figure 3 As shown, a bypass hole 24 for the pressure reducing pipe 4 on the filter frame 2 with a high horizontal height to pass through is provided on the filter frame 2 with a low horizontal height. Preferably, a positioning block 15 is provided on the assembly groove 11, and a positioning groove 25 is provided on the frame 21. Whenever a plurality of filter frames 2 are arranged in sequence in the assembly groove 11, the positioning groove 25 is matched with the positioning block 15, and the bypass hole 24 and the assembly hole 14 for the same pressure reducing pipe 4 to pass through are on the same straight line, so that the pressure reducing pipe 4 can directly pass through the assembly hole 14 and the bypass hole 24 to be connected to the pressure reducing hole 23.

[0029] As a preferred solution of the above embodiment, a collecting chamber 3 is also formed between the filter frame 2 located at the bottom and the bottom of the collecting box 1. The bottom of the collecting box 1 has a supporting leg 16. The drainage head 13 is located at the bottom of the collecting box 1 and has a length less than the length of the supporting leg 16. The drainage head 13 is connected to a drainage pipe 17. The drainage pipe 17 and the pressure reducing pipe 4 are both "L"-shaped, and both include a horizontal section and a vertical section connected to each other. A water head measuring sensor 6 is provided on the vertical section. Specifically, the water head value in each collecting chamber 3 is detected by the water head measuring sensor 6 provided on the drainage pipe 17 and the pressure reducing pipe 4, and whether the collecting chamber 3 corresponding to the drainage pipe 13 and the pressure reducing pipe 4 is blocked is determined based on the water head value, thereby ensuring the accuracy of the test results. In specific implementation, each collecting chamber 3 has a water head value range. When the value detected by the water head measuring sensor 6 exceeds the water head value range, it is determined that the collecting chamber 3 is blocked, and the test results finally obtained are invalidated. The blocked collecting chamber 3 is desilted and re-tested to ensure the accuracy of the test results.

[0030] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A device for collecting lost particles in a coarse-grained soil anti-filtration protection test, characterized in that: The invention is arranged below a coarse-grained soil anti-filtration protection test device, and comprises a collection box (1). The top port of the collection box (1) has an assembly slot (11). Five filter frames (2) assembled in the assembly slots (11) are arranged in sequence from bottom to top inside the collection box. The filter frames (2) have a plurality of filter holes. The filter holes on the filter frames (2) have increasing apertures from bottom to top, which are 0.1 mm, 0.25 mm, 0.5 mm, 2 mm and 5 mm respectively. There is a gap between two adjacent filter frames (2) to form a collection chamber (3). Each of the collection chambers (3) is connected to a pressure reducing pipe (4) extending out of the collection box (1). A drainage chamber (12) is provided between the filter frame (2) and the collection box (1) at the bottom. The drainage chamber (12) has a drainage head (13). The filter frame (2) comprises a frame (21) for being mounted in the assembly groove (11), and elastic layers (22) are laid on both the upper and lower surfaces of the frame (21); when the coarse-grained soil anti-filtration protection test device is placed on the filter frame (2) located at the top, the elastic layer (22) is in a compressed state.

2. The device for collecting lost particles in the coarse-grained soil anti-filtration protection test according to claim 1 is characterized in that: The collecting box (1) has a box wall provided with assembly holes (14) that match the plurality of pressure reducing pipes (4) one by one, the filter frame (2) has a pressure reducing hole (23), the pressure reducing pipes (4) pass through the assembly holes (14) and are screwed to the pressure reducing holes (23), and a sealing sleeve (41) is also provided at the portion of the pressure reducing pipe (4) that contacts the assembly holes (14).

3. The device for collecting lost particles in the coarse-grained soil anti-filtration protection test according to claim 2 is characterized in that: A water seepage component (5) is provided at one end of the pressure reducing pipe (4) close to the filter frame (2), and the water seepage component (5) comprises an assembly cylinder (51) screwed to the pressure reducing pipe (4), a plurality of water seepage holes are provided on the cylinder wall of the assembly cylinder (51), and a water seepage cloth (52) is wrapped on the outer side, and the end away from the pressure reducing pipe (4) is a closed end and is sleeved with an outer cover (53) to form a closed cavity (54), and a vibration motor (55) is arranged in the closed cavity (54).

4. The device for collecting lost particles in a coarse-grained soil anti-filtration protection test according to claim 3 is characterized in that: The filter frame (2) with a lower level is provided with an avoidance hole (24) for the pressure reducing pipe (4) on the filter frame (2) with a higher level to pass through; The assembly groove (11) is provided with a positioning block (15), and the frame (21) is provided with a positioning groove (25). Whenever a plurality of the filter frames (2) are sequentially arranged in the assembly groove (11), the positioning groove (25) matches the positioning block (15), and the avoidance hole (24) and the assembly hole (14) for allowing the same pressure reducing pipe (4) to pass through are located on the same straight line.

5. The device for collecting lost particles in a coarse-grained soil anti-filtration protection test according to any one of claims 1 to 4, characterized in that: The bottom of the collection box (1) is provided with a supporting leg (16); the drainage head (13) is located at the bottom of the collection box (1) and has a length smaller than the length of the supporting leg (16).

6. The device for collecting lost particles in a coarse-grained soil anti-filtration protection test according to claim 5, characterized in that: A collecting chamber (3) is also formed between the filter frame (2) located at the bottom and the bottom of the collecting box (1). A drainage pipe (17) is connected to the drainage head (13). The drainage pipe (17) and the pressure reducing pipe (4) are both "L" shaped and include a horizontal section and a vertical section. A water head measuring sensor (6) is provided on the vertical section.

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