Static cone penetration experiment device and method suitable for soft soil with different characteristics

Abstract

The invention discloses a static sounding experiment device and method suitable for soft soil with different characteristics, solves the problem that the static sounding experiment in the prior art is relatively single, and has the beneficial effects of flexibility and capability of carrying out various experiments. Comprising a box body, an experimental soil body is arranged in the box body, a load applying assembly is arranged in the box body, the load applying assembly applies a load to the experimental soil body, the load applying assembly can be separated from the experimental soil body to replace the experimental soil body, the box body detachably supports a water tank, the water tank is communicated with a water guide pipe, and the water guide pipe penetrates into the experimental soil body and is provided with a plurality of water seepage holes. Water flows into an experimental soil body through the water tank and the water guide pipe so as to change the water content of the experimental soil body, the box body supports the multidirectional moving mechanism, and the multidirectional moving mechanism is connected with the static sounding probe rod so as to change the position of the static sounding probe rod probing into the experimental soil body and drive the static sounding probe rod probing into the experimental soil body.

Description

Technical Field

[0001] The invention relates to the field of static penetration test, in particular to a static penetration test device and method suitable for soft soils with different characteristics. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] As an in-situ testing technology, static penetration testing uses quasi-static force to press a cone probe of a certain specification and shape into the soil through a series of probe rods at a constant penetration rate. At the same time, the resistance encountered by the probe during the penetration process is used to indirectly determine the physical and mechanical properties of the soil based on the measured penetration resistance. This technology is suitable for soft soil, general clay soil, silt, sandy soil and soil containing a small amount of gravel. Its principle is based on the measurement of the penetration resistance of the soil to the probe. When the probe is pressed into the soil at a constant rate, it will be subject to the cone tip resistance and side wall friction resistance from the soil. The size of the resistance is closely related to the physical and mechanical properties of the soil. By measuring these resistance values, the properties of the soil layer can be indirectly determined.

[0004] The application of static penetration testing in soft soil exploration has many advantages, such as fast, continuous and accurate direct measurement of soil penetration resistance index to obtain soil properties, and the required working space is small, which is advantageous for small-scale soil exploration. However, it also has certain defects, such as:

[0005] The experimental devices are all fixed, not flexible enough, and complicated to disassemble, which is not conducive to the replacement of the experimental soil, and cannot carry out experiments related to changes in moisture content;

[0006] Because the experimental device is mainly used in laboratories, the floor of the laboratory is flat, so the experimental device does not need to be leveled. However, it takes time to bring the excavated soil to the laboratory, and the soil is relatively soft and not easy to transport over long distances, which affects the accuracy of static penetration. The current demand is to conduct experiments directly at the excavation site, but the excavation site is not flat enough and the site environment is relatively complex. It is impossible to level the device using existing equipment, which affects the accuracy and reliability of the test results. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a static penetration test device suitable for soft soils with different characteristics. By adding quantitative water, replacing the soil and applying load, the static penetration test of soft soil under different soil properties, moisture content, load and porosity conditions can be realized.

[0008] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0009] A device for static penetration testing of soft soils with different characteristics comprises a box body, a test soil body is arranged in the box body, a load applying assembly is arranged in the box body, the load applying assembly applies a load toward the test soil body, the load applying assembly can be separated from the test soil body to replace the test soil body, the box body can detachably support a water trough, the water trough is connected to a water pipe, the water pipe penetrates into the test soil body, the water pipe is provided with a plurality of seepage holes, water flows into the test soil body through the water trough and the water pipe to change the water content of the test soil body, the box body supports a multi-directional moving mechanism, the multi-directional moving mechanism is connected to a static penetration probe rod to change the position of the static penetration probe rod penetrating into the test soil body, and drives the static penetration probe rod to penetrate into the test soil body.

[0010] As described above, a static penetration test device suitable for soft soils with different characteristics is provided, wherein the multi-directional moving mechanism is installed on the top of the box, the multi-directional moving mechanism includes a cross-shaped moving mechanism and a lifting mechanism, the cross-shaped moving mechanism is connected to the lifting mechanism, the lifting mechanism is fixed to the box, and the static penetration probe rod is arranged through the cross-shaped moving mechanism and is detachably connected to the cross-shaped moving mechanism.

[0011] As described above, a device for static penetration testing suitable for soft soils with different characteristics is provided, wherein the slider of the cross-shaped moving mechanism is provided with an extension plate, the static penetration probe rod is provided with a ring in the circumferential direction, the ring is provided with a mounting hole, and the fastener passes through the mounting hole and is detachably connected to the slider. Because after the static penetration probe rod is fixed to the cross-shaped moving mechanism, the static penetration probe rod is prone to interfere with the cross-shaped moving mechanism during the movement of the cross-shaped moving mechanism, the cross-shaped moving mechanism and the static penetration probe rod are detachably connected, and the static penetration probe rod can be removed before the cross-shaped moving mechanism adjusts the position of the static penetration probe rod.

[0012] As described above, a static penetration test device suitable for soft soils with different characteristics is provided with a supporting edge inside the box body, and ears are provided on the peripheral side of the water tank, and the supporting edge supports the ears of the water tank.

[0013] As described above, a static penetration test device suitable for soft soils with different characteristics is described, wherein the load application assembly includes a power mechanism and a fixed column, the power mechanism and the fixed column are arranged on opposite sides of the experimental soil body, the peripheral side of the experimental soil body is in contact with the fixed plate and the power plate, the power mechanism is connected to the power plate, the fixed column is connected to the fixed plate, and a sealing film is arranged on the bottom and peripheral side of the experimental soil body, and the sealing film is in contact with the fixed plate and the power plate to avoid water loss during the experiment.

[0014] As described above, a static penetration test device suitable for soft soils with different characteristics is provided, wherein a bottom plate is provided at the bottom of the box body, and a leveling knob, a support column and a support hinge are provided between the bottom plate and the box body, the support column connects the bottom plate and the box body, the leveling knob can adjust the horizontality of the bottom plate, and the leveling knob and the support hinge are located on both sides of the support column.

[0015] As described above, a static penetration test device suitable for soft soils with different characteristics, the bottom of the box is arranged beyond the side wall, and a leveling bubble is arranged at the bottom of the box, and the leveling bubble is observed.

[0016] The static penetration test device suitable for soft soils with different characteristics as described above, wherein a plurality of V-shaped grooves are arranged at the bottom of the water tank, and the bottom of the V-shaped grooves is connected to the water pipe;

[0017] The portion of the water pipe inserted into the experimental soil body is provided with a plurality of seepage holes, and a distance is set between two adjacent seepage holes. From the top to the bottom of the experimental soil body, the inner diameter of the seepage hole gradually decreases.

[0018] As described above, a static penetration test device suitable for soft soils with different characteristics is provided with a cover plate on the top of the test soil body, the size of the cover plate is larger than the size of the test soil body, the cover plate is provided with a penetration hole and a water injection hole, and the water pipe is provided through the water injection hole.

[0019] In a second aspect, the present invention further provides a static penetration test method applicable to soft soils with different characteristics, using the static penetration test device applicable to soft soils with different characteristics, comprising the following contents:

[0020] An experimental soil body is set in the box;

[0021] A load applying component is arranged in the box, and the load applying component is in contact with the test soil;

[0022] Water flows into the test soil through the water pipe to change the water content of the test soil. After a set time, the multi-directional moving mechanism drives the static penetration rod to move toward the test soil to achieve a static penetration test. The load application component is changed to continue to apply force to the test soil. Multiple static penetration tests are carried out to obtain static penetration test data under the same water content and different loads.

[0023] For the same test soil, keep the force applied to the test soil, change the water content, and conduct static penetration test, so as to obtain static penetration test data under the same load and different water content conditions;

[0024] Replace the test soil, maintain the moisture content of the test soil, maintain the force applied to the test soil, and conduct static penetration test to facilitate obtaining static penetration test data under different soil qualities and the same characteristic parameters;

[0025] The load application component applies a force toward the test soil to change the porosity of the soil, fix the water content and load, and conduct a penetration test to obtain static penetration test data under different porosities.

[0026] The beneficial effects of the present invention are as follows:

[0027] (1) The present application uses a multi-directional moving mechanism to drive the static penetration probe rod to move and change the position of the static penetration probe rod to conduct multiple experiments on the test soil. The lifting assembly drives the static penetration probe rod to move and drive the static penetration probe rod to penetrate the test soil to achieve the penetration and extraction of the probe rod. The water trough is movable to facilitate the removal and replacement of the test soil. The water trough supplies water to the test soil through a water pipe to change the water content of the test soil. The setting of the load application assembly can realize experiments under different loads. Moreover, the overall experiment does not rely on manual experience, and the test data is directly obtained through the static penetration probe rod to ensure the accuracy and reliability of the experiment.

[0028] (2) In the present application, a plurality of penetration holes are provided on the cover plate, and static penetration tests with different measuring ranges and measuring intervals can be realized by replacing the cover plate.

[0029] (3) The present application provides a base plate at the bottom of the experimental device, and installs two leveling knobs and two supporting hinges. The leveling knobs are set diagonally. By adjusting the leveling knobs and observing the leveling bubbles, the experimental soil is kept in a horizontal state, thereby ensuring that the static penetration probe can penetrate the experimental soil at a vertical angle, thereby ensuring the accuracy of the static penetration probe's sounding results.

[0030] (4) The present application provides a load application mechanism, in which two hydraulic plates and two support plates are installed in an experimental box, and are connected to the box through hydraulic columns and fixed columns respectively. The hydraulic columns and fixed columns are arranged adjacent to each other, and the hydraulic plates are driven by hydraulic rods to apply load to the soil, thereby changing the stress state and porosity (compaction degree) of the experimental soil.

[0031] (5) The present application provides a moisture content changing mechanism, in which a water tank is installed in the box, and water pipes are set in four directions and inserted into the soil. A certain amount of water is injected into the water tank, and the water seeps into the experimental soil under the action of pressure or gravity, thereby changing the moisture content of the soil.

[0032] (6) The present application provides a water infiltration mechanism. When the water pipe is inserted into the soil at different positions, seepage holes are set according to the principle of larger holes at the top and smaller holes at the bottom, so as to increase the seepage pressure at the bottom and increase the seepage efficiency. A permeable membrane is coated at the seepage hole of the water pipe to prevent the soil from blocking the seepage hole, thereby ensuring that the water in the water pipe is completely infiltrated into the experimental soil under the action of pressure.

[0033] (7) The present application provides a method for static penetration testing of different types of soft soils. By changing the soil quality of the penetration test soil, fixing the moisture content, load and other conditions, the penetration test is carried out to obtain static penetration test data under different soil qualities and the same characteristic parameters.

[0034] (8) The present application provides a method for static penetration test of soft soil with different moisture contents. The soil moisture content is changed by adding different amounts of water, and the soil quality, load and other conditions are fixed to conduct a penetration test to obtain static penetration test data of a certain soil with different moisture contents.

[0035] (9) The present application provides a method for static penetration testing of soft soil under different loads. By setting different loads to simulate the stress state of the soil, fixing conditions such as water content, and conducting penetration tests, static penetration test data of a certain soil under different loads are obtained.

[0036] (10) The present application provides a static penetration test method for soft soil with different porosities. By setting different loads to compact the soil to change the soil porosity, fixing the moisture content, load and other conditions, and conducting a penetration test, the static penetration test data of a certain soil type under different porosities are obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0038] Figure 1 It is a cross-sectional view of a static penetration test device suitable for soft soils with different characteristics according to one or more embodiments of the present invention.

[0039] Figure 2 It is a top view of a static penetration test device suitable for soft soils with different characteristics according to one or more embodiments of the present invention.

[0040] Figure 3 It is a schematic diagram of an experimental process of a static penetration test device suitable for soft soils with different characteristics according to one or more embodiments of the present invention.

[0041] Figure 4 It is a schematic diagram of the cooperation between a static penetration test rod and a cross-shaped moving mechanism slider in a static penetration test device suitable for soft soils with different characteristics according to one or more embodiments of the present invention.

[0042] In the figure: the distances or sizes between parts are exaggerated to show the positions of various parts, and the schematic diagram is for reference only.

[0043] Among them: 1-static penetration probe rod, 2-cross-shaped moving mechanism, 3-sliding rod, 4-box, 5-bottom plate, 6-leveling bubble, 7-leveling knob, 8-support column, 9-support hinge, 10-hydraulic column, 11-power plate, 12-fixed plate, 13-fixed column, 14-cover plate; 17-fixed edge, 18-water trough, 19-water guide pipe, 20-seepage hole, 21-experimental soil, 22-sliding block, 23-extending plate, 24-ring. DETAILED DESCRIPTION

[0044] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0045] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless otherwise explicitly stated in the present invention, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof;

[0046] As introduced in the background technology, the static penetration test device in the prior art is not flexible enough and is only applicable to laboratories. In order to solve the above technical problems, the present invention proposes a static penetration test device suitable for soft soils with different characteristics.

[0047] Embodiment 1

[0048] In a typical embodiment of the present invention, reference is made to Figure 1 , Figure 2 As shown, a static penetration test device suitable for soft soils with different characteristics includes a box 4, which supports the test soil, a load application component and a penetration component. The penetration component includes a static penetration probe rod 1, which is installed on a cross-shaped moving mechanism 2. The static penetration probe rod 1 moves toward the bottom of the box to achieve penetration into the test soil.

[0049] Moreover, the cross-shaped moving mechanism 2 specifically selects the existing cross-shaped linear slider assembly, the cross-shaped moving mechanism is connected to the lifting mechanism, the lifting mechanism can be a linear electric cylinder, and there are multiple linear electric cylinders. The fixed end of the linear electric cylinder is fixed to the side wall of the box 4, and the telescopic end of the linear electric cylinder is connected to the multi-directional moving mechanism to drive the movement of the static sounding probe 1 to achieve the smooth progress of the static sounding.

[0050] It is easy to understand that reference Figure 4As shown, the slider 22 on the upper layer of the cross-shaped moving mechanism is provided with an overhanging plate 23, and the static contact probe rod 1 is circumferentially provided with a collar 24, which is a T-shaped collar, and a mounting hole is provided on the collar. Fasteners such as bolts pass through the mounting hole and are detachably connected to the slider 22. Because after the static contact probe rod 1 is fixed to the cross-shaped moving mechanism, the static contact probe rod 1 is prone to interfere with the cross-shaped moving mechanism during the movement of the cross-shaped moving mechanism. Therefore, the cross-shaped moving mechanism and the static contact probe rod are detachably connected. Before the cross-shaped moving mechanism adjusts the position of the static contact probe rod, the static contact probe rod can be removed to avoid interference.

[0051] The width of the experimental soil body 21 is smaller than the width of the box, the length of the experimental soil body 21 is smaller than the length of the box, and the experimental soil body is arranged in the middle of the box;

[0052] It is easy to understand that the bottom of the box body 4 is arranged beyond the side wall, and a leveling bubble is arranged at the bottom of the box body. By observing the leveling bubble 6, it can be known whether the box body 4 is in a horizontal state.

[0053] In this embodiment, a bottom plate 5 is set at the bottom of the box body 4, and the bottom plate 5 is connected to the bottom of the box body 4 through a leveling knob 7, a support column 8 and a support hinge 9 respectively. The leveling knob 7 can realize the up and down movement of the box body 4. Two leveling knobs 7 can be set, which are diagonally arranged at the bottom of the box body 4. The support column 8 is set in the middle of the box body 4 and is a cylindrical structure. The support column is arranged along the center line of the width direction of the bottom of the box body; the support hinge 9 is also diagonally arranged at the bottom of the box body 4. The support hinge 9 can be rotated in the middle. When the leveling knob 7 is adjusted, the box body 4 can be rotated at a set angle to ensure that the box body 4 is in a horizontal state.

[0054] Among them, the leveling knob 7 specifically includes a screw rod, a nut is arranged circumferentially on the screw rod, the top end of the screw rod cooperates with the bottom of the box body 4 through a threaded structure, and the bottom end of the screw rod cooperates with the bottom plate 5 through a threaded structure. The nut is rotated to adjust the horizontality of the box body.

[0055] It is easy to understand that the load application assembly is arranged inside the box, the load application assembly includes a power mechanism and a fixed column 13, a support plate is arranged at the bottom of the experimental soil body 21, a fixed plate and a power plate are arranged on the surrounding side of the experimental soil body, the power mechanism is connected to the power plate 11, the fixed column 13 is connected to the fixed plate 12, the fixed plate 12 and the power plate 11 are in contact with the experimental soil body 21, when the experimental soil body 21 is rectangular, the power plate and the fixed plate are arranged on the four sides of the experimental soil body, a power mechanism is arranged in the X direction, and another power mechanism is arranged in the Y direction, and the power mechanism is arranged opposite to the fixed column 13;

[0056] The power mechanism is specifically a hydraulic cylinder, a fixed end of the hydraulic cylinder is fixed to the inner side of the box body 4, and a telescopic end of the hydraulic cylinder is connected to a power plate. The power plate can move forward and backward relative to the experimental soil body 21, and acts on the experimental soil body 21 to apply load; the cover plate 14 covers the experimental soil body 21, and together with the power plate 11 and the fixed plate 12, forms a closed space of the soil body. The cover plate 14 is provided with water injection holes 15 and sounding holes 16, which cooperate with the sounding assembly and the water injection assembly to realize the change of the experimental soil body characteristics.

[0057] Among them, the side of the cover plate 14 is provided with an existing movable buckle, and the top outer sides of the power plate and the fixed plate are respectively provided with convex parts that cooperate with the movable buckle. The cover plate can be fixedly connected with the power plate and the fixed plate through the movable buckle.

[0058] It should be noted that the water injection assembly is used to supply water to the experimental soil. A support edge 17 is arranged inside the box 4, and a water trough 18 is supported by the support edge 17. The water trough 18 is respectively provided with V-shaped grooves at the four corners. The water trough 18 is detachable relative to the support edge 17. A water pipe 19 is arranged at the bottom of the water trough. The water pipe 19 is inserted into the experimental soil 21 from the water injection hole 15 at the top of the experimental soil. The water pipe is provided with a plurality of seepage holes 20. From the top to the bottom of the experimental soil, the inner diameter of the seepage hole 20 of the water pipe gradually decreases, thereby effectively improving the seepage efficiency.

[0059] Among them, it is easy to understand that the cross-shaped moving mechanism, the lifting mechanism, and the load applying assembly are separately connected to the control assembly, and the control assembly is specifically a PLC controller or other types of controllers, and the actions of each mechanism are controlled by the control assembly; in addition, the static penetration probe rod is also connected to the control assembly. The static penetration probe rod is an existing static penetration probe rod, which has a pressure sensor itself. During the process of penetrating the test soil, the penetration pressure and other data can be obtained and sent to the control assembly.

[0060] The device provided in the present application can drive the static penetration probe rod to move and change the position of the static penetration probe rod through a multi-directional moving mechanism to conduct multiple experiments on the experimental soil. The lifting assembly drives the static penetration probe rod to move to drive the static penetration probe rod to penetrate into the experimental soil, thereby realizing the penetration and extraction of the probe rod. The movably arranged water trough is convenient for taking out and replacing the experimental soil. The water trough supplies water to the experimental soil through a water pipe to change the moisture content of the experimental soil. The setting of the load applying assembly can realize experiments under different loads. Moreover, the overall experiment does not rely on manual experience, and the test data is directly obtained through the static penetration probe rod to ensure the accuracy and reliability of the experiment.

[0061] Embodiment 2

[0062] This embodiment provides a static penetration test method applicable to soft soils with different characteristics. Figure 3As shown, a static penetration test device suitable for soft soils with different characteristics as described in Example 1 is used, including the following contents:

[0063] An experimental soil body is set in the box;

[0064] A load applying component is arranged in the box, and the load applying component is in contact with the test soil;

[0065] Water flows into the test soil through the water pipe to change the water content of the test soil. After a set time, the multi-directional moving mechanism drives the static penetration rod to move toward the test soil to achieve a static penetration test. The load application component is changed to continue to apply force to the test soil. Multiple static penetration tests are carried out to obtain static penetration test data under the same water content and different loads.

[0066] For the same test soil, keep the force applied to the test soil, change the water content, and conduct static penetration test, so as to obtain static penetration test data under the same load and different water content conditions;

[0067] Replace the test soil, maintain the moisture content of the test soil, maintain the force applied to the test soil, and conduct static penetration test to facilitate obtaining static penetration test data under different soil qualities and the same characteristic parameters;

[0068] The load application component applies a force toward the test soil to change the porosity of the soil, fix the water content and load, and conduct a penetration test to obtain static penetration test data under different porosities.

[0069] Specifically, the test steps for static penetration test of different types of soft soil are as follows:

[0070] ① Level the device and prepare experimental soil of different soil qualities 21;

[0071] ② Operate the hydraulic column 10 to form a closed space with the two power plates 11 and the fixed plate 12, and fill the closed space with the test soil 21;

[0072] ③ Select cover plates 14 of different sizes according to the size of the experimental soil, and fix them on the experimental soil 21 through movable buckles;

[0073] ④ The multi-directional moving mechanism 2 is actuated to move the static penetration probe rod 1 above the penetration hole 16 and perform position calibration;

[0074] ⑤ The multi-directional moving mechanism 2 is actuated to make the static penetration probe rod 1 penetrate downward into the test soil 21, and the test data is recorded;

[0075] ⑥ Replace the penetration hole 16, repeat steps ④ and ⑤, record the experimental data, and finally obtain the static penetration test data under the soil;

[0076] ⑦ Replace the experimental soil 21 and repeat the above steps.

[0077] (2) Test steps for static penetration test of soft soil with different moisture contents:

[0078] ① Level the device and prepare the experimental soil 21;

[0079] ② Operate the hydraulic column 10 to form a closed space with the two power plates 11 and the fixed plate 12, cover it with a sealing film (specifically, a plastic film with a set thickness to prevent water loss), and fill it with the experimental soil 21;

[0080] ③ Select cover plates 14 of different sizes according to the size of the experimental soil, and fix them on the experimental soil 21 through movable buckles;

[0081] ④ Check the patency of the water injection module, install the water tank 18, and penetrate the water pipe 19 into the experimental soil 21, and cover the bottom side with a permeable membrane to ensure that the water seepage hole 20 is unobstructed;

[0082] ⑤ According to the water content designed in the experiment, calculate the water injection volume q (refer to formula 1) and measure the water injection volume;

[0083] q=G s ·ω (1)

[0084] in,

[0085] q—water injection volume, g;

[0086] G s —Dry weight of soil, g;

[0087] ω—moisture content, %.

[0088] ⑥ Pour water into the water tank 18, and then inject it into the experimental soil 21 through the water pipe 19, and set a static time to allow the water to fully penetrate; if the water pipe 19 has not completely penetrated, manually pressurize it by pressure injection to make the soil reach the moisture content designed in the experiment;

[0089] ⑦ The multi-directional moving mechanism 2 is actuated to move the static penetration probe rod 1 above the penetration hole 16 and perform position calibration;

[0090] ⑧ The multi-directional moving mechanism 2 is actuated to make the static penetration probe rod 1 penetrate downward into the test soil 21 and record the test data;

[0091] ⑨Replace the penetration hole 16, repeat steps ⑦⑧, record the experimental data, and finally obtain the static penetration test data of the moisture content;

[0092] ⑩Change the moisture content, calculate the amount of water to be injected each time and add it according to the sequence of moisture content from small to large, and repeat the above steps.

[0093] (3) Test steps for soft soil static penetration test under different loads:

[0094] ① Level the device and prepare experimental soil of different soil qualities 21;

[0095] ② Operate the hydraulic column 10 to form a closed space with the two power plates 11 and the fixed plate 12, and fill the closed space with the test soil 21;

[0096] ③ Select a suitable cover plate 14 according to the size of the test soil, and fix it on the test soil 21 through a movable buckle;

[0097] ④ Operate the hydraulic column 10 to add the experimental design load;

[0098] ⑤ The multi-directional moving mechanism 2 is actuated to move the static penetration probe rod 1 above the penetration hole 16 and perform position calibration;

[0099] ⑥ The multi-directional moving mechanism 2 is actuated to make the static penetration probe rod 1 penetrate downward into the test soil 21 and record the test data;

[0100] ⑦ Replace the penetration hole 16, repeat steps ⑤⑥, record the experimental data, and finally obtain the static penetration test data under the set load;

[0101] ⑧Continue to operate the hydraulic column 10, change the load, and repeat the above steps.

[0102] (4) Test steps for static penetration test of soft soil with different porosity:

[0103] ① Level the device and prepare experimental soil of different soil qualities 21;

[0104] ② Operate the hydraulic column 10 to form a closed space with the two power plates 11 and the fixed plate 12, and fill the closed space with the test soil 21;

[0105] ③ Select a suitable cover plate 14 according to the size of the test soil, and fix it on the test soil 21 through a movable buckle;

[0106] ④ Operate the hydraulic column 10 to apply a set load so that the soil reaches a set porosity, and calculate the porosity according to formula (2);

[0107] n=-AlogP+C (2)

[0108] In the formula,

[0109] n—porosity;

[0110] A—Compression index, which is the slope of the compression curve;

[0111] P—load;

[0112] C—Porosity of loose soil at 70kPa.

[0113] ⑤ The multi-directional moving mechanism 2 is actuated to move the static penetration probe rod 1 above the penetration hole 16 and perform position calibration;

[0114] ⑥ The multi-directional moving mechanism 2 is actuated to make the static penetration probe rod 1 penetrate downward into the test soil 21 and record the test data;

[0115] ⑦ Replace the penetration hole 16, repeat steps ⑤⑥, record the experimental data, and finally obtain the static penetration test data under the soil;

[0116] ⑧Replace the experimental soil 21 and repeat the above steps.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A static penetration test device suitable for soft soils with different characteristics, characterized in that: The invention comprises a box body, an experimental soil body is arranged in the box body, a load applying assembly is arranged in the box body, the load applying assembly applies a load toward the experimental soil body, the load applying assembly can be separated from the experimental soil body to replace the experimental soil body, the box body can detachably support a water trough, the water trough is connected with a water pipe, the water pipe penetrates into the experimental soil body, the water pipe is provided with a plurality of seepage holes, water flows into the experimental soil body through the water trough and the water pipe to change the moisture content of the experimental soil body, the box body supports a multi-directional moving mechanism, the multi-directional moving mechanism is connected with a static penetration probe rod to change the position of the static penetration probe rod penetrating into the experimental soil body, and drives the static penetration probe rod to penetrating into the experimental soil body.

2. A static penetration test device suitable for soft soils with different characteristics according to claim 1, characterized in that: The multidirectional moving mechanism is installed on the top of the box, and the multidirectional moving mechanism includes a cross-shaped moving mechanism and a lifting mechanism. The cross-shaped moving mechanism is connected to the lifting mechanism, and the lifting mechanism is fixed to the box. The static contact probe rod passes through the cross-shaped moving mechanism and is detachably connected to the cross-shaped moving mechanism.

3. A static penetration test device suitable for soft soils with different characteristics according to claim 2, characterized in that: The slider of the cross-shaped moving mechanism is provided with an outward extension plate, the static contact probe rod is circumferentially provided with a collar, the collar is provided with a mounting hole, and the fastener passes through the mounting hole and is detachably connected with the slider.

4. The static penetration test device suitable for soft soils with different characteristics according to claim 1, characterized in that: A supporting edge is arranged inside the box body, and an ear edge is arranged on the peripheral side of the water tank, and the supporting edge supports the ear edge of the water tank.

5. The static penetration test device suitable for soft soils with different characteristics according to claim 1, characterized in that: The load applying assembly comprises a power mechanism and a fixed column, the power mechanism and the fixed column are arranged on opposite sides of the experimental soil body, the peripheral side of the experimental soil body is in contact with the fixed plate and the power plate, the power mechanism is connected to the power plate, the fixed column is connected to the fixed plate, and a sealing film is arranged on the bottom and peripheral side of the experimental soil body.

6. The static penetration test device suitable for soft soils with different characteristics according to claim 1, characterized in that: A base plate is arranged at the bottom of the box body, and a leveling knob, a support column and a support hinge are arranged between the base plate and the box body. The support column connects the base plate and the box body, the leveling knob can adjust the horizontality of the base plate, and the leveling knob and the support hinge are located on both sides of the support column.

7. The static penetration test device suitable for soft soils with different characteristics according to claim 6, characterized in that: The bottom of the box body is arranged beyond the side wall, and a leveling bubble is arranged at the bottom of the box body, and the leveling bubble is observed.

8. The static penetration test device suitable for soft soils with different characteristics according to claim 1, characterized in that: The bottom of the water tank is provided with a plurality of V-shaped grooves, and the bottom of the V-shaped grooves is connected with the water guide pipe; The portion of the water pipe inserted into the experimental soil body is provided with a plurality of seepage holes, and a distance is set between two adjacent seepage holes. From the top to the bottom of the experimental soil body, the inner diameter of the seepage hole gradually decreases.

9. The static penetration test device applicable to soft soils with different characteristics according to claim 1, characterized in that: A cover plate is arranged on the top of the experimental soil body, the size of the cover plate is larger than the size of the experimental soil body, the cover plate is provided with a sounding hole and a water injection hole, and the water guide pipe is arranged through the water injection hole.

10. A static penetration test method suitable for soft soils with different characteristics, characterized in that: A static penetration test device suitable for soft soils with different characteristics according to any one of claims 1 to 9 is used, comprising the following contents: An experimental soil body is set in the box; A load applying component is arranged in the box, and the load applying component is in contact with the test soil; Water flows into the test soil through the water pipe to change the water content of the test soil. After a set time, the multi-directional moving mechanism drives the static penetration rod to move toward the test soil to achieve a static penetration test. The load application component is changed to continue to apply force to the test soil. Multiple static penetration tests are carried out to obtain static penetration test data under the same water content and different loads. For the same test soil, keep the force applied to the test soil, change the water content, and conduct static penetration test, so as to obtain static penetration test data under the same load and different water content conditions; Replace the test soil, maintain the moisture content of the test soil, maintain the force applied to the test soil, and conduct static penetration test to facilitate obtaining static penetration test data under different soil qualities and the same characteristic parameters; The load application component applies a force toward the test soil to change the porosity of the soil, fix the water content and load, and conduct a penetration test to obtain static penetration test data under different porosities.

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