Soil pressure testing device and implementation method

Abstract

The present application belongs to the technical field of soil pressure testing in geotechnical engineering, and a soil pressure testing device comprises an operating frame, a loading plate, a horizontal counterforce support and a soil test block baffle. The four vertical rods on the operating frame guide the loading plate, the horizontal counterforce support installed on the operating frame beam guides the soil test block baffle, and the spring force on the horizontal counterforce support simulates the lateral confinement condition of the surrounding soil of the undisturbed soil. The device can well reflect the mechanical properties of the soil under the action of the surrounding soil in situ. Compared with the current testing device, the gap between the measured soil parameters and the undisturbed soil is reduced, and the measured soil pressure replaces the soil lateral pressure calculated by the traditional soil lateral pressure calculation theory. The present application has the advantages of simple structure, easy operation, consideration of the lateral confinement condition of the soil, and more reliable measurement of the soil pressure. The present application also provides an implementation method for soil pressure testing.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of soil pressure testing in geotechnical engineering, and particularly relates to a soil pressure testing device and an implementation method. BACKGROUND

[0002] In the field of geotechnical mechanics and engineering, the size and distribution of soil pressure load are the key problems to be studied. Soil pressure is one of the main loads acting on the supporting structure, and determining the size and distribution shape of soil pressure is of great significance to the safety of supporting structure and optimization design. The classical Coulomb or Rankine soil pressure calculation theory has been adopted by engineering due to its simplicity and clear mechanical concept, but due to the complexity of geotechnical engineering problems, it is not easy to obtain satisfactory results, so model test and field test are still the main research methods in this field.

[0003] Meanwhile, the compression consolidation experiment of soil in the indoor experiment is usually carried out under the condition of complete lateral confinement or no lateral confinement, which cannot well reflect the lateral confinement condition of the surrounding soil in situ, so that the measured soil parameters are greatly different from the undisturbed soil, and cannot be directly used for design calculation. SUMMARY

[0004] To solve the above problems, the present application provides a soil pressure testing device, which can simulate the lateral confinement condition of undisturbed soil surrounding, and the measured soil pressure can replace the soil lateral pressure calculated by the traditional soil lateral pressure calculation theory. The present application also provides a soil pressure testing implementation method.

[0005] To achieve the above purpose, the technical scheme adopted by the present application is:

[0006] In the first technical scheme, a soil pressure testing device comprises an operating frame, a loading device, a horizontal counterforce support and a soil test block baffle, wherein

[0007] The operating frame comprises a baffle moving surface with a flat and smooth top surface, and the operating frame is provided with a crossbeam on both sides in the first direction;

[0008] The front surface of the soil test block baffle body is two half-cylinder plates cut along the axial direction, and the main bodies of the two half-barrel structures can be spliced to form a cylindrical structure, the internal cavity of the cylindrical structure is used for placing soil test blocks, the two half-cylinder plates are placed on the baffle moving surface, and the back surface of the half-cylinder plate is provided with a vertical baffle vertically arranged and perpendicular to the first direction, and four guide mounting holes are arranged on the two side baffles;

[0009] The horizontal counterforce support comprises two side-limit adjusting plates, several nuts and four screw rods and eight springs, the middle section of the screw rod is a light section, the screw rod is inserted into a guide mounting hole, the eight springs are sleeved outside the four screw rods, the side-limit adjusting plate has a light hole, the side-limit adjusting plate is sleeved on the screw rod through the light hole, and the two side-limit adjusting plates are located on the two sides of the two semicylindrical plates respectively, the first end of the spring abuts against the outer side surface of the vertical baffle, the second end of the spring abuts against the inner side surface of the side-limit adjusting plate, and the nut is connected to the screw rod in a threaded mode and abuts against the outer side of the side-limit adjusting plate.

[0010] The combination of the horizontal counterforce support and the soil test block baffle is placed on the operation frame, the soil test block baffle is placed on the baffle moving surface, and the horizontal counterforce support is connected to the cross beam through the screw rod.

[0011] In the first technical scheme, preferably, the inner wall of the semicylindrical plate is provided with a pressure sensor for measuring the pressure value of the soil test block on the inner wall of the semicylindrical plate during the loading process of the loading device.

[0012] In the first technical scheme, preferably, the cross beam is provided with a dial indicator, the testing end of the dial indicator abuts against the outer side surface of the vertical baffle, and the dial indicator is used to measure the displacement distance of the vertical baffle in the horizontal direction.

[0013] In the first technical scheme, preferably, the connecting transition of the semicylindrical plate and the vertical baffle is provided with a rib plate for strengthening the strength of the semicylindrical plate.

[0014] In the first technical scheme, preferably, the inner side of the side-limit adjusting plate and / or the outer side of the vertical baffle is provided with a spring limiting ring for positioning the spring.

[0015] In the first technical scheme, preferably, the loading device is a loading plate, and the loading plate comprises a guide plate and a plate-shaped load plate.

[0016] The operation frame comprises a bottom plate and a stand column located at the top surface of the four corners of the bottom plate, the guide plate is provided with through holes at the four corners, the guide plate is installed on the stand column through the through holes and can vertically slide along the stand column, the load plate is fixedly connected to the bottom surface of the guide plate, the load plate corresponds to the open end of the top of the cylindrical structure, and the shape and area of the load plate are consistent with the open end of the top of the cylindrical structure.

[0017] In the first technical scheme, preferably, the baffle moving surface is a high-fiber ceramic plate, and the circular baffle of the soil test block is a plate body made of polytetrafluoroethylene material.

[0018] In the first technical scheme, preferably, the size of the internal cavity of the cylindrical structure is D=100 mm and H=200 mm.

[0019] In a second technical solution, an implementation method of soil pressure testing, using the soil pressure testing device as described in the first technical solution, comprising the following steps:

[0020] S1, making soil test block: immediately after taking soil sample on site, make soil sample into standard soil test block. The size is: D=100mm, H=200mm, avoid disturbance to soil test block during production; the collection of test sample should comply with the relevant provisions of Chapter 4 of "Highway Geotechnical Test Procedures" JTG E40-2007; the preparation process of soil sample should comply with the provisions of Article 16-3 of "Standard for Soil Test Methods" GB / T50123-1999;

[0021] S2, debugging and checking instrument: before testing, check whether each sensor can be used normally to ensure that the whole testing process can work normally, clean and smooth the soil test block baffle moving surface and screw rod 9 without foreign matter, and smear lubricant to reduce friction;

[0022] S3, placing soil test block. Remove the loading plate, remove the soil test block baffle, and place the soil test block at the designated position; return the baffle to its original position, adjust the position of the side limit adjusting plate to make the spring initially free to stretch, without pressing the soil test block baffle, and place the dial gauge measuring end on the side surface and clear zero;

[0023] S4, applying load: place the loading plate on the operating frame vertical rod, apply load above the guide plate, unload after the displacement of the two soil test block semicircular baffles is stable, and record the soil pressure value on the pressure sensor and the maximum reading of the dial gauge during the process through the computer.

[0024] S5, side limit adjustment: adjust the position of the side limit adjusting plate to make the spring produce different initial lateral forces, repeat steps S1-S4, apply load to read the pressure sensor value and the soil lateral displacement value on the dial gauge until the test data is complete;

[0025] S6, after the test is completed, unload the loader and restore the initial position of each instrument, clean the inside of the soil test block baffle and the baffle moving surface, so as to facilitate the next test.

[0026] Beneficial effects:

[0027] The test device can provide support for lateral displacement during the test of the soil test block baffle through the setting of the horizontal counterforce support, simulate the side limit condition of the surrounding original soil through the applied force of the spring, make the performance test of the soil test block closer to the real state, and test the change of the form of the soil test block during the test through the installed pressure sensor and dial gauge, and the measured soil pressure instead of the soil lateral pressure calculated by the traditional soil lateral pressure calculation theory. The overall structure of the device is simple and easy to use, suitable for repeated testing and measurement, maintenance-free in later period, and low in production cost. Attached Figure Description

[0028] Figure 1 This is an overall isometric schematic diagram of the earth pressure testing device of the present invention.

[0029] Figure 2 This is a front view of the earth pressure testing device of the present invention.

[0030] Figure 3 This is a schematic diagram of the operating frame in the earth pressure testing device of the present invention.

[0031] Figure 4 This is a schematic diagram of the loading plate in the earth pressure testing device of the present invention.

[0032] Figure 5 This is a schematic diagram of the horizontal reaction brace in the earth pressure testing device of the present invention.

[0033] Figure 6 This is a schematic diagram of the soil test block baffle in the earth pressure testing device of the present invention.

[0034] The reference numerals in the figures include:

[0035] In the diagram: 1-Operating frame, 2-Loading plate, 3-Horizontal reaction brace, 4-Soil test block baffle, 5-Baffle moving surface, 6-Dial gauge, 7-Guide plate, 8-Loading plate, 9-Screw, 10-Nut, 11-Side limit adjustment plate, 12-Spring, 13-Spring limit ring, 14-Semi-cylindrical plate, 15-Vertical baffle, 16-Rib plate, 17-Pressure sensor. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this technical solution clearer, the following detailed description, in conjunction with specific embodiments, further illustrates this technical solution. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this technical solution.

[0037] Example 1

[0038] like Figures 1-6 As shown, this embodiment proposes an earth pressure testing device, including an operating frame 1, a loading device, a horizontal reaction brace 3, and a soil test block baffle 4, wherein...

[0039] The operating frame 1 includes a baffle moving surface 5 with a flat and smooth top surface, and the operating frame 1 is provided with crossbeams on both sides in the first direction;

[0040] The front of the soil block baffle 4 body is two axially split semicylindrical plates 14, and the two semicylindrical plate bodies can be spliced to form a cylindrical structure, the internal cavity of the cylindrical structure is used for placing the soil block, the two semicylindrical plates 14 are placed on the baffle moving surface 5, and the back of the semicylindrical plate 14 is provided with a vertical baffle 15 arranged vertically and perpendicular to the first direction, and four guide mounting holes are arranged on the two side baffles.

[0041] The horizontal counterforce support 3 includes two side limit adjustment plates 11, a plurality of nuts 10 and four screw rods 9 and eight springs 12, the middle section of the screw rod 9 is a light section, the screw rod 9 is inserted into the guide mounting hole, the eight springs 12 are sleeved outside the four screw rods 9, the side limit adjustment plate 11 has a light hole, the side limit adjustment plate 11 is sleeved on the screw rod 9 through the light hole, and the two side limit adjustment plates 11 are respectively located on the two sides of the two semicylindrical plates 14, the first end of the spring 12 abuts against the outer side surface of the vertical baffle 15, the second end of the spring 12 abuts against the inner side surface of the side limit adjustment plate 11, and the nut 10 is connected to the screw rod 9 through threads and abuts against the outer side of the side limit adjustment plate 11.

[0042] The combination of the horizontal counterforce support 3 and the soil block baffle 4 is placed on the operation frame 1, the soil block baffle 4 is placed on the baffle moving surface 5, and the horizontal counterforce support 3 is connected to the cross beam through the screw rod 9.

[0043] Specifically, as shown in Figure 1 The operation frame 1 is the overall support of the device, the soil block baffle 4 is a fixed device for loading the soil block, and the horizontal counterforce support 3 supports the horizontal counterforce support of the outward expansion of the soil block baffle 4 during the test loading process.

[0044] As shown in Figure 2 The bottom of the operation frame 1 has a bottom plate, the top surface of the bottom is the baffle moving surface 5, and the top surface of the baffle moving surface 5 is a smooth horizontal surface to avoid generating a large friction force when the soil block baffle 4 moves on the top surface. As shown in Figure 1 In the operation frame 1, the four corners of the top surface of the bottom plate are provided with columns, the columns are cylinders, and the columns provide a guiding effect on the loading plate 2. The loading plate 2 includes a guide plate 7 connected to the operation frame 1 through the column guide, and the guide plate 7 is connected to the load plate 8 through a fixed connection and non-retractable rod structure.

[0045] The loading plate 2, the horizontal counter-force support 3 and the soil test block baffle 4 are connected with each other through the operation frame 1, the operation frame 1 is a frame structure composed of vertical rods, cross beams and a bottom plate, a smooth baffle moving surface 5 is bonded on the bottom plate, and a dial gauge 6 is installed on the right cross beam; the loading plate 2 comprises a guide plate 7 and a load plate; the guide plate 7 is provided with vertical holes at four corners and can slide up and down on the vertical rods of the operation frame 1; the load plate is vertically connected with the guide plate 7; the horizontal counter-force support 3 is mainly composed of four symmetrically arranged screw rods 9, the screw rods 9 pass through the semicircular soil retaining plate of the soil test block from front to back and are connected to the cross beams of the operation frame 1 through nuts 10 on the two sides, side limit adjusting plates 11 and springs 12 are symmetrically arranged on the inner side of the operation frame 1, and spring limit rings 13 are connected to the inner side of the side limit adjusting plates 11; the soil test block baffle 4 is composed of two semicylindrical plates 14 which are engaged with each other, the outer side is a vertical baffle 15, the semicylindrical plate 14 and the vertical baffle 15 are connected into an integrated whole and are provided with three rib plates 16 between each other, the inner side of the semicylindrical plate 14 is provided with a groove and is installed with a pressure sensor 17, the side of the vertical baffle 15 is provided with a through hole for the horizontal counter-force support 3 to pass through, and the spring limit ring 13 is connected around the through hole, and the whole is placed on the baffle moving surface 5 on the bottom plate of the operation frame 1.

[0046] As shown in Figure 3 , the operation frame 1 is provided with two cross beams between the two vertical rods on the left side and the two vertical rods on the right side, the cross beams are provided with horizontal through holes for the screw rods 9 to pass through, and the dial gauge 6 is arranged on one of the cross beams. The baffle moving surface 5 is a high-fiber ceramic plate with a thickness of 5 mm, the surface is smooth and is bonded on the sub-bottom plate of the operation frame 1; the dial gauge 6 is installed on the sub-cross beam of the operation frame 1 and is placed on the side of the soil test block baffle 4 during measurement to measure the displacement of the baffle.

[0047] As shown in Figure 4 , the guide plate 7 is provided with through holes at four corners, the guide plate 7 is installed on the vertical rods through the through holes and can slide vertically along the vertical rods, the load plate 8 is fixedly connected to the bottom surface of the guide plate 7, the load plate 8 corresponds to the open top end of the cylindrical structure, and the shape and area of the load plate 8 are consistent with the open top end of the cylindrical structure. The loading plate 2 comprises the guide plate 7 and the load plate, the thicknesses of the guide plate 7 and the load plate are 5 mm and 10 mm respectively, and the guide plate 7 can slide up and down on the vertical rods of the operation frame 1; the load plate is vertically connected with the guide plate 7, and the size of the load plate is consistent with the size of the circular cylinder opening of the soil test block baffle 4 in the engaged state.

[0048] As shown in Figure 5As shown, the side limit adjusting plate 11 in the horizontal counterforce support 3 provides lateral support for the spring 12, the spring 12 abuts the outer side of the vertical baffle 15 and is used to apply a horizontal support force to the vertical baffle 15. In the initial stage of the test, the vertical baffle 15 is in a free state. When the test soil under the loading plate 2 is compressed, the vertical baffle 15 tends to move outward, and the spring 12 abuts the vertical baffle 15 to apply a lateral support force to the vertical baffle 15. In addition, there are 16 nuts 10 on the screw rod 9, four on the inner side and eight on the outer side. The nuts 10 are screwed with the screw rod 9 and are used to position the horizontal position of the side limit adjusting plate 11 to prevent lateral movement of the side limit adjusting plate 11 during the test. The eight nuts 10 on the outer side are used to position the horizontal counterforce support 3 on the operating frame 1.

[0049] The main body of the horizontal counterforce support 3 is four symmetrically arranged screw rods 9, which pass through the semicircular soil retaining plate of the soil test block from front to back and are connected to the crossbeam of the operating frame 1 through nuts 10 on both sides. The side limit adjusting plate 11 and the spring 12 are symmetrically arranged on the inner side of the operating frame 1, and the spring limiting ring 13 is connected to the side limit adjusting plate 11. The screw rod 9 has a diameter of 12 mm and is symmetrically arranged above and below the circular soil retaining plate of the soil test block. The screw rod 9 has threads at the ends, which are installed on the crossbeam of the operating frame 1 through nuts 10, and the middle section is smooth and passes through the circular soil retaining plate of the soil test block. The side limit adjusting plate 11 can be fixed at different positions on the screw rod 9 through nuts 10. When the end of the spring 12 remains stationary on the side of the circular soil retaining plate of the soil test block, different fixed positions on the screw rod 9 are marked with scales to indicate the size of the spring force 12 under the current lateral limit condition. The spring 12 is sleeved on the screw rod 9, and the two ends are placed in the spring limiting ring 13 to ensure that the spring force 12 is horizontal and perpendicular to the side of the circular soil retaining plate of the soil test block.

[0050] As shown in Figure 6 The inner wall of the semicylindrical plate 14 has a pressure sensor 17 for measuring the pressure value of the soil test block on the inner wall of the semicylindrical plate 14 during the loading process of the loading device. The transition between the semicylindrical plate 14 and the vertical baffle 15 is provided with a rib plate 16 for strengthening the strength of the semicylindrical plate 14. In addition, the abutting portion of the two semicylindrical plates 14 has a stepped structure, which has a certain guiding effect and facilitates the assembly of the two semicylindrical plates 14. When the two semicylindrical plates 14 are assembled together, the stepped structures at the protruding positions on the inner sides of the two semicylindrical plates 14 can be engaged with each other.

[0051] The soil test block baffle 4 consists of two interlocking semi-cylindrical plates 14, with a vertical baffle 15 on the outer side. The cylindrical dimensions are: D = 100mm, H = 200mm, and the plate thickness is 10mm. The semi-cylindrical plates 14 and the vertical baffle 15 are connected as one piece, with three ribs 16 between them. The two semi-cylindrical plates 14 have an interlocking joint and are rotationally symmetrical about the center. The inner side of the semi-cylindrical plates 14 has a groove and a pressure sensor 17 is installed there. The pressure sensor 17 is connected to a computer for easy recording. The pressure value at each loading moment is recorded. The side of the vertical baffle 15 has an opening for the horizontal reaction support 3. The diameter of the opening is equal to the diameter of the screw 9. A spring limit ring 13 is connected around the opening to ensure that the force of the spring 12 is perpendicular to the side of the vertical baffle 15. The soil test block baffle 4 is made of polytetrafluoroethylene (PTFE). Using this material can reduce its own weight and increase its lubrication, so that when it is placed on the baffle moving surface 5 on the bottom plate of the operating frame 1 and moves to both sides, the friction is small, thus reducing the measurement error.

[0052] A dial indicator 6 is installed on the crossbeam, with its test end abutting against the outer side of the vertical baffle 15. The dial indicator 6 is used to measure the horizontal displacement distance of the vertical baffle 15. In this embodiment, the test end of the dial indicator 6 passes through the side limiting adjustment plate 11 on one side and abuts against the outer side of the vertical baffle 15, making its structure more compact.

[0053] like Figure 4 and Figure 5 As shown, a spring limiting ring 13 for positioning the spring 12 is provided on the inner side of the side limiting adjustment plate 11 and / or the outer side of the vertical baffle 15.

[0054] Preferably, the moving surface 5 of the baffle is a high-fiber ceramic plate, and the baffle 4 of the soil test block is a plate made of polytetrafluoroethylene material.

[0055] Example 2

[0056] This embodiment proposes a method for conducting earth pressure testing, using the earth pressure testing device as described in Embodiment 1, including the following steps:

[0057] S1. Preparation of Soil Specimens: After taking soil samples on site, immediately prepare standard soil specimens. The dimensions are: D = 100 mm, H = 200 mm. Avoid disturbing the soil specimens during preparation. Sample collection should comply with the relevant provisions of Chapter 4 of the "Specifications for Geotechnical Testing of Highways" JTG E40-2007. The soil sample preparation process should comply with Article 16-3 of the "Standard for Geotechnical Testing Methods" GB / T50123-1999.

[0058] S2. Debugging and checking instruments: Before the test, check whether each sensor can be used normally to ensure that the whole test process can work normally. Clean the moving surface of the soil test block baffle 4 and the screw 99 to make them smooth and free of foreign objects, and apply lubricant to reduce friction.

[0059] S3, put the soil test block. Take off the loading plate 2, remove the soil test block baffle 4, put the soil test block to the designated position; put the baffle in place, adjust the position of the side limit adjusting plate 11 so that the spring 12 is initially free to stretch, does not squeeze the soil test block baffle 4, place the dial gauge 6 measuring end on the side and clear zero;

[0060] S4, apply load: put the loading plate 2 on the vertical rod of the operation frame 1, apply load above the guide plate 7, load until the displacement of the two soil test block semicircular baffles is stable, then unload, record the soil pressure value on the pressure sensor 17 through the computer during the process, and record the maximum reading of the dial gauge 6.

[0061] S5, side limit adjustment: adjust the position of the side limit adjusting plate 11 so that the spring 12 generates different initial lateral forces, repeat steps S1-S4, apply load, read the pressure sensor 17 value and the soil lateral displacement value on the dial gauge 6 until the test data is complete.

[0062] S6, after the test is finished, unload the loader, and restore the initial position of each instrument, clean the inside of the soil test block baffle 4 and the baffle moving surface 5, so as to facilitate the next test.

[0063] The above is only the preferred embodiment of the present application, for those skilled in the art, according to the technical content of the idea, in the specific implementation and application range can make many changes, as long as these changes do not deviate from the concept of the present application, all belong to the protection scope of the present patent.

Claims

1. A soil pressure testing device, characterized by: The operation frame, the loading device, the horizontal counterforce support and the soil test block baffle, wherein The operation frame comprises a baffle moving surface with a flat and smooth top surface, and the operation frame is provided with a crossbeam on both sides in the first direction; The front surface of the soil test block baffle body is a half-cylindrical plate cut along the axial direction, and the two half-barrel-shaped structures can be spliced to form a cylindrical structure, the internal cavity of the cylindrical structure is used for placing the soil test block, the two half-cylindrical plates are placed on the baffle moving surface, and the back surface of the half-cylindrical plate is provided with a vertical baffle arranged perpendicularly to the first direction, and four guide mounting holes are arranged on the two side baffles; The horizontal counterforce support comprises two side limit adjusting plates, a plurality of nuts and four screw rods and eight springs, the middle section of the screw rod is a light section, the screw rod is inserted into the guide mounting hole, the eight springs are sleeved outside the four screw rods, the side limit adjusting plate has a light hole, the side limit adjusting plate is sleeved on the screw rod through the light hole, and the two side limit adjusting plates are respectively located on the two sides of the two half-cylindrical plates, the first end of the spring abuts against the outer side surface of the vertical baffle, the second end of the spring abuts against the inner side surface of the side limit adjusting plate, and the nut is connected with the screw rod through threads and abuts against the outer side of the side limit adjusting plate; The combination of the horizontal counterforce support and the soil test block baffle is placed on the operation frame, the soil test block baffle is placed on the baffle moving surface, and the horizontal counterforce support is connected with the crossbeam through the screw rod; The loading device is a loading plate, and the loading plate comprises a guide plate and a plate-shaped load plate; The operation frame comprises a bottom plate and a stand column arranged at the top surface of the four corners of the bottom plate, the guide plate is provided with through holes at the four corners, the guide plate is mounted on the stand column through the through holes and can vertically slide along the stand column, the load plate is fixedly connected to the bottom surface of the guide plate, the load plate corresponds to the open top end of the cylindrical structure, and the shape and area of the load plate are consistent with the open top end of the cylindrical structure.

2. The earth pressure testing device of claim 1, wherein: The inner wall of the half-cylindrical plate is provided with a pressure sensor for measuring the pressure value of the soil test block on the inner wall of the half-cylindrical plate during the loading process of the loading device.

3. The earth pressure testing device of claim 1, wherein: A dial indicator is arranged on the crossbeam, the testing end of the dial indicator abuts against the outer side surface of the vertical baffle, and the dial indicator is used for measuring the displacement distance of the vertical baffle in the horizontal direction.

4. The earth pressure testing device of claim 1, wherein: A rib plate is arranged at the connection transition of the half-cylindrical plate and the vertical baffle to strengthen the strength of the half-cylindrical plate.

5. The earth pressure testing device of claim 1, wherein: The inner side of the side limit adjusting plate and / or the outer side of the vertical baffle are provided with a spring limiting ring for positioning the spring.

6. The earth pressure testing device of claim 1, wherein: The baffle moving surface is a high-fiber ceramic plate, and the circular soil test block baffle is a plate body made of polytetrafluoroethylene material.

7. The earth pressure testing device of claim 1, wherein: The size of the internal cavity of the cylindrical structure is D=100 mm and H=200 mm.

8. A method of performing a soil pressure test using the soil pressure testing device of any one of claims 1 to 7, the method comprising: The method comprises the following steps: S1, making soil test blocks: immediately make soil test blocks after collecting soil samples on site, the size of the soil test blocks is D=100 mm and H=200 mm, and the making process avoids disturbance to the soil test blocks; the collection of the test samples shall meet the relevant provisions in Chapter 4 of the Highway Soil Test Regulations JTGE40-2007; The soil test block preparation process shall meet the provisions in Article 16-3 of the Soil Test Method Standard GB / T 50123-1999; S2, debugging check instrument: before the test, check whether each sensor can be used normally, ensure that the whole test process can work normally, move the soil test block baffle and the screw rod clean and smooth without foreign matter, smear lubricant to reduce friction; S3, put the soil test block, take down the loading plate, move away the soil test block baffle, put the soil test block to the designated position; put the baffle in place, adjust the position of the lateral limit adjusting plate to make the spring initial free stretching state, do not squeeze the soil test block baffle, put the dial gauge measuring end on the side and clear zero; S4, apply load: put the loading plate on the operation frame vertical rod, apply load above the guide plate, load to two soil test block semicircular baffle displacement stable after unloading, in this process, record the soil pressure value on the pressure sensor through the computer, and record the maximum reading of the dial gauge; S5, lateral limit adjustment: adjust the position of the lateral limit adjusting plate to make the spring produce different initial lateral force, repeat steps S1-S4, apply load to read the pressure sensor value and the soil lateral displacement value on the dial gauge until the test data is complete; S6, after the test, unload the loader, and restore the initial position of each instrument, clean the inside of the soil test block baffle and the baffle moving surface, so as to prepare for the next test.

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