Device and method for testing strength of ocean sediments in different consolidation states

Abstract

The invention discloses a device and a method for testing the strength of ocean sediments in different consolidation states. The device comprises a test board, a test barrel, a door-shaped stress application rod and a sample container, wherein a precise pressurizing device is mounted at the bottom of the test board; the test barrel and the door-shaped stress application rod are arranged on the test board; a mechanical sensor and a pressurizing rod displacement sensor are arranged in the precise pressurizing device; the sample container is provided with a cover plate, two sides of the sample container are provided with cross-shaped holes, and the testing barrel is provided with two mechanical property testing devices matched with the testing barrel. According to the testing method, the downward displacement of the pressing block and the volume of discharged water are measured at the same time, consolidation compression parameters of the sediment are calculated, the accuracy of a consolidation compression experiment is effectively improved, and the penetration resistance test and the shear strength test are measured through the mechanical property testing device. According to the invention, a sediment consolidation compression experiment, a penetration resistance test and a shear strength test can be completed by using one ocean sediment sample, and particularly, the device has obvious advantages for obtaining deep-sea sediment samples with relatively high cost and relatively small sample amount.

Description

Technical Field

[0001] The present invention relates to a testing device and technology for the multi-parameter mechanical properties of seabed and intertidal zone sediment samples, and more specifically to a strength testing device and method for marine sediments in different consolidation states. The device can simultaneously measure three independent soil mechanical parameters of the sediments and can be used for the analysis and detection of sedimentary pollutants. The device belongs to the field of marine geological experimental equipment and sediment testing technology. Background Art

[0002] When conducting research related to marine sedimentation and marine engineering geology, marine sediment samples must be analyzed and tested. Sediment compression properties, penetration resistance, shear strength, and other soil strength parameters are key test indicators. Sedimentary pollutants, such as sludge, require specific instrumentation to analyze their various properties and identify targeted pollution control solutions.

[0003] Traditional experimental methods primarily involve removing a sediment column from a sampler and then preparing multiple sediment samples from top to bottom for compression, penetration, and shear strength tests. These tests present the following challenges: 1) The required sample size is large. For example, a traditional shear strength test requires four sediment samples per test. Combined with the penetration and compression tests, each set of tests requires a relatively long sediment column. 2) Due to the large sample length required for each test, variations in the physical and mechanical properties of the sediment occur between different test items or between different samples within a single test item, making it impossible to accurately and precisely measure the mechanical properties of each sediment layer.

[0004] Therefore, designing a sediment strength index testing device under a predetermined consolidation state to solve the problems of traditional experimental devices, such as large sample requirements, inaccurate test sample depth, and differences in sediment samples corresponding to different test indicators, is a technical problem that needs to be solved urgently. Summary of the Invention

[0005] The present invention aims to provide a device and method for testing the strength of marine sediments in different consolidation states, so as to overcome the deficiencies of the prior art.

[0006] A device for testing the strength of marine sediments in different consolidation states, characterized by comprising a test bench with a precision pressurizing device mounted on the bottom, and a gate-shaped pressurizing rod. The two column feet at the bottom of the gate-shaped pressurizing rod pass through two openings on the test bench and are fixed to the precision pressurizing device. The precision pressurizing device is internally provided with a mechanical sensor and a pressurizing rod displacement sensor. A circular groove for fixing the test barrel is provided between the two openings at the upper part of the test bench, and a square storage platform is provided in the middle of the bottom of the test barrel, on which a sample container is placed, and the sample container comprises a square barrel-shaped body with a water-permeable hole at the bottom, and a cross-shaped opening is provided in the middle of each of the two opposite side walls of the square barrel-shaped body, and a guide groove is provided at the upper end of the cross-shaped opening to facilitate the cross plate to penetrate the interior of the sample container; a rectangular pressure block is provided under the gate-shaped pressure rod, and the pressure block can move vertically inside the sample container; the precision pressure device can drive the gate-shaped pressure rod to move downward, thereby providing a downward high-precision pressure to the pressure block, and at the same time measuring the downward displacement of the gate-shaped pressure rod and the pressure block during the experiment; Two mechanical property testing devices are symmetrically arranged between the test barrel and the sample container; A water outlet is provided on the side of the barrel wall at a position higher than the sample container. The water outlet is connected to an ultra-high precision flow meter through a pipeline. The outlet of the ultra-high precision flow meter is connected to a liquid bottle with a scale through a pipeline. A circle of annular concave platforms are provided on the inner side of the test barrel, above the water outlet, and a transparent cover plate is provided on the annular concave platforms. The size of the cover plate matches that of the annular concave platforms, and a square opening is provided in the middle of the cover plate. The opening is consistent with the cross-sectional size of the pressure block to prevent evaporation of water during the experiment; The mechanical sensor, the pressure rod displacement sensor and the ultra-high precision flow meter are connected to the host computer via a data transmission interface.

[0007] The mechanical property testing device includes a crossbar, which is divided into three parts in the horizontal direction: a front end is a cylinder, a middle part is a smooth square rod, and a rear part is a cylinder with annular tooth patterns on the surface; A test cross plate and a protection cross plate of the same size are installed at the front end of the cross bar. The test cross plate is fixed to the front end of the cross bar, and the protection cross plate cannot move forward and backward relative to the cross bar, but can rotate freely around the cross bar. Both the test cross plate and the protection cross plate can be inserted into the cross-shaped opening. A torsion motor and a torque sensor are installed on the square rod in the middle of the crossbar, and the torsion motor and the torque sensor are fixed on the upper surface of the bottom plate of the test barrel through a base; A penetration motor and a resistance sensor are installed on the toothed cylinder at the rear of the crossbar, and the penetration motor and the resistance sensor are fixed to the inner side of the barrel wall of the test barrel through a base; The torque sensor and the resistance sensor are connected to the host computer via a data transmission interface.

[0008] The device also includes filter paper, permeable stone, and impermeable stone used according to the requirements of drainage consolidation or undrained consolidation during the experiment, wherein the filter paper and permeable stone are used to simulate the drainage process, and the filter paper and impermeable stone are used to simulate the undrained process, and the cross-sectional size of the permeable stone or impermeable stone is consistent with the storage table.

[0009] The cross section of the pressure block is a square, and the side length of the square is equal to the inner side length of the sample container.

[0010] The wall thickness of the sample container is consistent with the transverse width of the protective cross plate.

[0011] The liquid bottle is suspended to keep it in a vertical position, which is convenient for accurate reading.

[0012] The strength testing device for marine sediments in different consolidation states also includes a sample preparation barrel that can be used during the experiment. The sample preparation barrel has a thin-walled structure, and its internal dimensions are consistent with the inner diameter of the sample container, and its height is less than the height of the sample container. A square recess is also provided on the inner side of the upper edge of the sample container, and the square recess is used to dock with the bottom of the sample preparation barrel.

[0013] The method for testing the strength of marine sediments in different consolidation states using the device is characterized by comprising the following steps: 1) Take out the original marine sediment core sample to be tested from the sample tube, obtain the experimental sediment sample at the designated location and prepare the sample according to the requirements; 2) Place the test barrel and sample container in the specified positions on the test table in sequence, and drive the crossbar forward by the penetration motor to insert the test cross plate into the cross-shaped opening; 3) Choose permeable stone or impermeable stone for the experiment according to the requirements of drainage or non-drainage during the experiment. When simulating the drainage process, place permeable stone and filter paper on the platform in sequence, place the sample to be tested in the sample container, and place filter paper and permeable stone on top of the sample in sequence. When simulating the non-drainage process, place impermeable stone and filter paper on the platform in sequence, place the sample to be tested in the sample container, and place filter paper and impermeable stone on top of the sample in sequence. 4) Gently place the pressure block on top of the permeable or impermeable stone in the sample container, place the transparent cover on the annular concave platform, set the initial pre-consolidation pressure using the precision pressure device, and drive the gate-shaped pressure rod downward until it contacts the pressure block and reaches the preset initial pre-consolidation pressure; 5) Pour water into the test barrel until water flows out of the water outlet. When the water level in the test barrel is flush with the bottom of the water outlet, return the displacement sensor of the precision pressurizing device and the ultra-high precision flow meter to zero, and record the volume of water in the liquid bottle at the same time. 6) After the consolidation test pressure and consolidation completion conditions are preset, the consolidation test begins. The precision pressurizing device drives the gate-shaped pressurizing rod downward. The displacement sensor and ultra-high-precision flow meter of the precision pressurizing device simultaneously record the change data of the parameters over time during the experiment. After the completion conditions of the consolidation test are met, the volume of water in the liquid bottle is recorded. 7) Control the penetration motor to push the test cross plate into the sediment in the sample container at a constant speed. During this process, the penetration motor drives the crossbar to advance a distance equal to the lateral width of the test cross plate, while protecting the cross plate from being embedded in the side wall of the sample container. During this process, the resistance sensor measures and records the change data of the penetration resistance; 8) Control the torsion motor to drive the crossbar and the test cross plate to rotate at a constant speed. During this process, the torque sensor measures and records the change data of the shear strength of the sediment; 9) After the experiment is completed, the torsion motor drives the test cross plate to reset, the penetration motor drives the test cross plate and the protection cross plate to reset, restore the door-shaped pressure rod to a certain height, remove the pressure block and sediment sample, rinse the test barrel and sample container with clean water, pour out the water in the liquid bottle, and then proceed to the next set of experiments. Beneficial effects

[0014] (1) Compared with the existing technology, the present invention can use a single marine sediment sample to complete sediment consolidation compression test, penetration resistance test and shear strength test, and can simultaneously measure three independent soil mechanical parameters of the sediment. This has significant advantages, especially for deep-sea sediment samples with high acquisition costs and small sample quantities.

[0015] (2) By simultaneously measuring the downward displacement of the pressure block during the experiment and the volume of water flowing out of the test barrel through the ultra-high precision flow meter, the initial volume of the sediment involved in the consolidation compression experiment can be accurately calculated, and then the consolidation compression parameters of the sediment can be accurately calculated, effectively improving the accuracy of the consolidation compression experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is one of the overall structural diagrams of the present invention.

[0017] Figure 2 This is the second schematic diagram of the overall structure of the present invention.

[0018] Figure 3 It is a structural schematic diagram of the test barrel of the present invention.

[0019] Figure 4 It is a schematic structural diagram of the sample container of the present invention.

[0020] Figure 5 It is a structural schematic diagram of the mechanical property testing device of the present invention.

[0021] Among them, 1. test bench, 2. test barrel, 3. sample container, 4. pressure block, 5. gate-shaped pressure rod, 6. mechanical property testing device, 7. ultra-high precision flow meter, 8. liquid bottle, 9. cover plate, 10. precision pressure device, 21. barrel wall, 22. bottom plate, 23. storage table, 24. annular concave platform, 31. square barrel body, 32. water-permeable hole, 33. cross-shaped opening, 34. guide groove, 61. test cross plate, 62. protection cross plate, 63. cross bar, 64. torsion motor, 65. torque sensor, 66. penetration motor, 67. resistance sensor. DETAILED DESCRIPTION

[0022] like Figures 1 to 5 As shown, a strength testing device for marine sediments in different consolidation states is characterized in that it includes a test bench 1 with a precision pressurizing device 10 installed at the bottom and a gate-shaped pressurizing rod 5, the two column feet at the bottom of the gate-shaped pressurizing rod 5 pass through two openings on the test bench 1 and are fixed to the precision pressurizing device 10, and a mechanical sensor and a pressurizing rod displacement sensor are provided inside the precision pressurizing device 10.

[0023] like Figure 2 、 3 , 4. A circular groove for fixing the test barrel 2 is provided between the two openings on the upper part of the test bench 1, and a square storage platform 23 is provided in the middle of the bottom of the test barrel 2. The sample container 3 is placed on the storage platform 23, and the sample container 3 includes a square barrel-shaped body 31, a water-permeable hole 32 is provided at the bottom, and a cross-shaped opening 33 is provided in the middle of each of the two opposite side walls of the square barrel-shaped body 31. A guide groove 34 is provided at the upper end of the cross-shaped opening 33 to facilitate the cross plate to penetrate the interior of the sample container 3; a rectangular pressure block 4 is provided under the gate-shaped pressure rod 5, and the pressure block 4 can move vertically inside the sample container 3; the precision pressure device 10 can drive the gate-shaped pressure rod 5 to move downward, thereby providing a downward high-precision pressure to the pressure block 4, and at the same time measuring the downward displacement of the gate-shaped pressure rod 5 and the pressure block 4 during the experiment.

[0024] like Figure 2 、 5 Two mechanical property testing devices 6 are symmetrically arranged between the test barrel 2 and the sample container 3. The mechanical property testing device 6 includes a crossbar 63. The crossbar 63 is divided into three parts in the horizontal direction: a front end is a cylinder, a middle part is a smooth square rod, and a rear part is a cylinder with annular tooth patterns on the surface; A test cross plate 61 and a protection cross plate 62 of the same size are installed at the front end of the cross bar 63. The test cross plate 61 is fixed to the front end of the cross bar 63, and the protection cross plate 62 cannot move forward or backward relative to the cross bar 63, but can rotate freely around the cross bar 63. The test cross plate 61 and the protection cross plate 62 can both be inserted into the cross-shaped opening 33. A torsion motor 64 and a torque sensor 65 are installed at the middle square bar of the crossbar. The torsion motor 64 and the torque sensor 65 are fixed to the upper surface of the bottom plate 22 of the test barrel 2 through a base. A penetration motor 66 and a resistance sensor 67 are installed at the toothed cylinder at the rear of the crossbar 63 . The penetration motor 66 and the resistance sensor 67 are fixed to the inner side of the barrel wall 21 of the test barrel 2 through a base.

[0025] like Figure 1 、 2 3. A water outlet is provided on the side of the barrel wall 21, above the sample container 3. The water outlet is connected to an ultra-high-precision flowmeter 7 via a pipeline. The outlet of the ultra-high-precision flowmeter 7 is also connected to a graduated liquid container 8 via a pipeline. The torque sensor, resistance sensor, force sensor, and pressure rod displacement sensor are connected to the host computer via a data transmission interface.

[0026] like Figure 1 、 2 3. A circle of annular recessed platforms 24 are provided on the inner side of the test barrel 2, above the water outlet. A transparent cover plate 9 is provided on the annular recessed platforms 24. The dimensions of the cover plate 9 match those of the annular recessed platforms 24. A square opening is provided in the middle of the cover plate 9. The opening has the same cross-sectional dimensions as the pressure block 4 to prevent evaporation of water during the experiment. The device also includes filter paper, permeable stone, and impermeable stone used according to the requirements of drainage consolidation or undrained consolidation during the experiment, wherein the filter paper and permeable stone are used to simulate the drainage process, and the filter paper and impermeable stone are used to simulate the undrained process, and the cross-sectional size of the permeable stone or impermeable stone is consistent with the storage platform 23.

[0027] The cross section of the pressure block 4 is a square, and the side length of the square is equal to the inner side length of the sample container 3 .

[0028] The wall thickness of the sample container 3 is consistent with the lateral width of the protective cross plate 62 .

[0029] The liquid bottle 8 is suspended to keep the liquid bottle 8 in a vertical state, which is convenient for accurate reading.

[0030] The device for testing the strength of marine sediments in different consolidation states is characterized in that it also includes a sample preparation barrel that can be used during the experiment. The sample preparation barrel has a thin-walled structure, and its internal dimensions are consistent with the inner diameter of the sample container 3, and its height is less than the height of the sample container 3; a square recess 35 is also provided on the inner side of the upper edge of the sample container 3, and the square recess 35 is used to dock with the bottom of the sample preparation barrel.

[0031] The device for testing the strength of sediments in different consolidation states described in the present invention can test the compression characteristics under fully confined conditions, the penetration resistance characteristics and shear strength characteristics under given overburden stress and consolidation state, and simultaneously measure three independent soil mechanics parameters of the sediment. It is particularly suitable for measuring the soil strength parameters of precious deep-sea columnar sediment samples with small sample quantities and high acquisition costs.

[0032] The method for testing the strength of marine sediments in different consolidation states using the device is characterized by comprising the following steps: 1) Take out the original marine sediment core sample to be tested from the sample tube, obtain the experimental sediment sample at the designated location and prepare the sample according to the requirements; 2) Place the test barrel 2 and the sample container 3 in the specified positions on the test table 1 in sequence, and drive the crossbar forward by the penetration motor 66 to insert the test cross plate 61 into the cross-shaped opening 33; 3) Select permeable stone or impermeable stone for the experiment according to the requirements of drainage or non-drainage during the experiment. When simulating the drainage process, place permeable stone and filter paper on the storage platform 23 in sequence, place the sample to be tested in the sample container 3, and place filter paper and permeable stone on top of the sample to be tested in sequence. When simulating the non-drainage process, place impermeable stone and filter paper on the storage platform 23 in sequence, place the sample to be tested in the sample container 3, and place filter paper and impermeable stone on top of the sample to be tested in sequence. 4) Gently place the pressure block 4 above the permeable or impermeable stone in the sample container 3, place the transparent cover plate 9 on the annular recessed platform 24, set the initial pre-consolidation pressure using the precision pressure device 10, and drive the gate-shaped pressure rod 5 downward until it contacts the pressure block 4 and reaches the preset initial pre-consolidation pressure; 5) Pour water into the test barrel 2 until water flows out of the water outlet. When the water level in the test barrel 2 is flush with the bottom of the water outlet, reset the displacement sensor of the precision pressurizing device 10 and the ultra-high-precision flowmeter 7 to zero, and simultaneously record the volume of water in the liquid bottle 8; 6) After the consolidation test pressure and consolidation completion conditions are preset, the consolidation test begins. The precision pressurizing device 10 drives the gate-shaped pressurizing rod 5 downward. The displacement sensor of the precision pressurizing device 10 and the ultra-high-precision flow meter 7 simultaneously record the change data of the parameters over time during the experiment. After the completion conditions of the consolidation test are met, the volume of water in the liquid bottle 8 is recorded. 7) Controlling the penetration motor 66 to push the test cross plate 61 into the sediment in the sample container 3 at a constant speed. During this process, the penetration motor 66 drives the cross bar 63 to advance a distance equal to the lateral width of the test cross plate 61, while simultaneously protecting the cross plate 62 from being embedded in the side wall of the sample container 3. During this process, the resistance sensor 67 measures and records the change in penetration resistance data; 8) Control the torsion motor 64 to drive the crossbar 63 and the test cross plate 61 to rotate at a constant speed. During this process, the torque sensor 65 measures and records the change data of the shear strength of the sediment; 9) After the experiment is completed, the torsion motor 64 drives the test cross plate 61 to reset, and the penetration motor 66 drives the test cross plate 61 and the protection cross plate 62 to reset. The gate-shaped pressure rod 5 is restored to a certain height, the pressure block 4 and the sediment sample are removed, the test barrel 2 and the sample container 3 are rinsed with clean water, and the water in the liquid bottle 8 is poured out before the next set of experiments can be carried out.

[0033] Clearly, the device of the present invention can simultaneously measure the compressive properties of sediments under fully confined conditions, the penetration resistance characteristics under a given overburden stress and consolidation state, and the shear strength characteristics. This device can simultaneously measure three independent geotechnical parameters of sediments and is particularly suitable for measuring parameters of deep-sea sediment core samples, which are relatively small and expensive to obtain.

Claims

1. A device for testing the strength of marine sediments in different consolidation states, characterized in that It comprises a test bench (1) with a precision pressurizing device (10) installed at the bottom and a gate-shaped pressurizing rod (5), wherein two column feet at the bottom of the gate-shaped pressurizing rod (5) pass through two openings on the test bench (1) and are fixed to the precision pressurizing device (10), and a mechanical sensor and a pressurizing rod displacement sensor are provided inside the precision pressurizing device (10); A circular groove for fixing the test barrel (2) is provided between the two openings on the upper part of the test table (1); a square storage platform (23) is provided in the middle of the bottom of the test barrel (2); a sample container (3) is placed on the storage platform (23); the sample container (3) comprises a square barrel-shaped body (31), a water-permeable hole (32) is provided at the bottom, a cross-shaped opening (33) is provided in the middle of two opposite side walls of the square barrel-shaped body (31), and a guide groove (34) is provided at the upper end of the cross-shaped opening (33) to facilitate the cross plate to penetrate into the interior of the sample container (3); a rectangular parallelepiped pressure block (4) is provided below the gate-shaped pressure rod (5), and the pressure block (4) can move vertically inside the sample container (3); the precision pressure device (10) can drive the gate-shaped pressure rod (5) to move up and down, thereby providing a downward high-precision pressure to the pressure block (4), and at the same time measure the downward displacement of the gate-shaped pressure rod (5) and the pressure block (4) during the experiment; Two mechanical property testing devices (6) are symmetrically arranged between the test barrel (2) and the sample container (3); A water outlet is provided on the side of the barrel wall (21) at a position higher than the sample container (3), the water outlet is connected to an ultra-high precision flow meter (7) through a pipeline, and the outlet of the ultra-high precision flow meter (7) is connected to a liquid container (8) with a scale through a pipeline; A circle of annular concave platforms (24) are provided on the inner side of the test barrel (2) and above the water outlet. A transparent cover plate (9) is provided on the annular concave platforms (24). The dimensions of the cover plate (9) and the annular concave platforms (24) match. A square opening is provided in the middle of the cover plate (9). The opening is consistent with the cross-sectional dimensions of the pressure block (4) to prevent evaporation of water during the experiment. The mechanical sensor, the pressure rod displacement sensor and the ultra-high precision flow meter (7) are connected to the host computer via a data transmission interface.

2. A device for testing the strength of marine sediments in different consolidation states according to claim 1, characterized in that The mechanical property testing device (6) includes a crossbar (63), which is divided into three parts in the horizontal direction: a front end that is a cylinder, a middle part that is a smooth square rod, and a rear part that is a cylinder with annular tooth patterns on the surface; A test cross plate (61) and a protection cross plate (62) of the same size are installed at the front end of the cross bar (63), the test cross plate (61) is fixed to the front end of the cross bar (63), and the protection cross plate (62) cannot move forward and backward relative to the cross bar (63), but can rotate freely around the cross bar (63); the test cross plate (61) and the protection cross plate (62) can both be embedded in the cross-shaped opening (33); A torsion motor (64) and a torque sensor (65) are installed at the middle square rod of the crossbar, and the torsion motor (64) and the torque sensor (65) are fixed to the upper surface of the bottom plate (22) of the test barrel (2) through a base; A penetration motor (66) and a resistance sensor (67) are installed at the toothed cylinder at the rear of the crossbar (63), and the penetration motor (66) and the resistance sensor (67) are fixed to the inner side of the barrel wall (21) of the test barrel (2) through a base; The torque sensor and the resistance sensor are connected to the host computer via a data transmission interface.

3. A device for testing the strength of marine sediments in different consolidation states according to claim 1, characterized in that The test device also includes filter paper, permeable stone, and impermeable stone used according to the requirements of drainage consolidation or undrained consolidation during the experiment, wherein the filter paper and permeable stone are used to simulate the drainage process, and the filter paper and impermeable stone are used to simulate the undrained process, and the cross-sectional size of the permeable stone or the impermeable stone is consistent with the storage platform (23).

4. A device for testing the strength of marine sediments in different consolidation states as claimed in claim 1, 2 or 3, characterized in that The cross section of the pressure block (4) is a square, and the side length of the square is equal to the inner side length of the sample container (3).

5. A device for testing the strength of marine sediments in different consolidation states as claimed in claim 1, 2 or 3, characterized in that The wall thickness of the sample container (3) is consistent with the transverse width of the protective cross plate (62).

6. A device for testing the strength of marine sediments in different consolidation states as claimed in claim 1, 2 or 3, characterized in that The liquid bottle (8) is suspended to keep the liquid bottle (8) in a vertical state, which facilitates accurate reading.

7. A device for testing the strength of marine sediments in different consolidation states as claimed in claim 1, 2 or 3, characterized in that It also includes a sample preparation barrel, which is a thin-walled structure, has an internal size consistent with the inner diameter of the sample container (3), and a height smaller than the height of the sample container (3); a square concave platform (35) is further provided on the inner side of the upper edge of the sample container (3), and the square concave platform (35) is used to dock with the bottom of the sample preparation barrel.

8. A method for testing the strength of marine sediments in different consolidation states using the apparatus of claim 3, characterized in that The following steps are involved: 1) Take out the original marine sediment core sample to be tested from the sample tube, obtain the experimental sediment sample at the designated location and prepare the sample according to the requirements; 2) placing the test barrel (2) and the sample container (3) in sequence at the specified positions on the test table (1), driving the crossbar forward by the penetration motor (66), and inserting the test cross plate (61) into the cross-shaped opening (33); 3) According to the requirements of drainage or non-drainage during the experiment, a permeable stone or an impermeable stone is selected for the experiment. When simulating the drainage process, a permeable stone and a filter paper are placed on the storage table (23) in sequence, and the sample to be tested is placed in the sample container (3). The filter paper and the permeable stone are placed on the top of the sample to be tested in sequence. When simulating the non-drainage process, an impermeable stone and a filter paper are placed on the storage table (23) in sequence, and the sample to be tested is placed in the sample container (3). The filter paper and the impermeable stone are placed on the top of the sample to be tested in sequence. 4) Gently place the pressure block (4) on top of the permeable stone or impermeable stone in the sample container (3), place the transparent cover (9) on the annular concave platform (24), set the initial pre-consolidation pressure through the precision pressure device (10), and drive the gate-shaped pressure rod (5) to move downward until it contacts the pressure block (4) and reaches the preset initial pre-consolidation pressure; 5) Pour water into the test barrel (2) until water flows out of the water outlet. When the water level in the test barrel (2) is flush with the bottom of the water outlet, return the displacement sensor of the precision pressurizing device (10) and the ultra-high precision flow meter (7) to zero, and record the volume of water in the liquid bottle (8) at the same time; 6) After the consolidation test pressure and consolidation completion conditions are preset, the consolidation test is started. The precision pressurizing device (10) drives the gate-shaped pressurizing rod (5) to move downward. The displacement sensor of the precision pressurizing device (10) and the ultra-high precision flow meter (7) simultaneously record the data of the change of parameters over time during the experiment. After the completion conditions of the consolidation test are reached, the volume of water in the liquid bottle (8) is recorded. 7) Controlling the penetration motor (66) to push the test cross plate (61) into the sediment in the sample container (3) at a uniform speed. During this process, the penetration motor (66) drives the cross bar (63) to advance a distance equal to the lateral width of the test cross plate (61), while protecting the cross plate (62) from being embedded in the side wall of the sample container (3). During this process, the resistance sensor (67) measures and records the change data of the penetration resistance; 8) controlling the torsion motor (64) to drive the crossbar (63) and the test cross plate (61) to rotate at a constant speed, and during this process, the torque sensor (65) measures and records the change data of the shear strength of the sediment; 9) After the experiment is completed, the torsion motor (64) drives the test cross plate (61) to reset, the penetration motor (66) drives the test cross plate (61) and the protection cross plate (62) to reset, the door-shaped pressure rod (5) is restored to a certain height, the pressure block (4) and the sediment sample are removed, the test barrel (2) and the sample container (3) are rinsed with clean water, and the water in the liquid bottle (8) is poured out before the next set of experiments can be carried out.

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