An in-situ soil testing device, system and method

Abstract

The application provides a soil in-situ testing device, system and method, relates to the technical field of static cone penetration devices, and provides the soil in-situ testing device, which comprises a soil expansion module, a shear wave velocity measuring module and a static cone penetration module connected in sequence from top to bottom; the soil expansion module comprises a supporting rod, an expansion film, an expansion pressure applying structure and at least one set of transverse displacement sensing components; the expansion film is sleeved on the outside of the supporting rod; the transverse displacement sensing components are arranged between the outer wall of the supporting rod and the expansion film; the expansion pressure applying structure is used for applying pressure to the expansion film to make the expansion film generate a transverse stress and measure the transverse stress; and the transverse displacement sensing components are used for monitoring the transverse displacement value of the expansion film generated by the transverse stress. The soil in-situ testing device, system and method can simultaneously perform static cone penetration, shear wave velocity data measurement and stress-strain data collection in the soil expansion process, and improve the static cone penetration operation efficiency.

Description

Technical Field

[0001] This invention relates to the field of static cone penetration testing technology, specifically to an in-situ soil testing device, system, and method. Background Technology

[0002] In recent years, my country's infrastructure construction has developed rapidly. Geotechnical engineering design requires accurate soil layer information. Clarifying the properties of the soil is an important step in analyzing the risk of soil liquefaction and assessing the bearing capacity of the foundation. Since testing undisturbed soil is difficult, geotechnical engineering field testing often relies on dynamic penetration testing (SPT, Standard Penetration Test) or static penetration testing (CPT). However, due to the large testing error and poor reproducibility of dynamic penetration testing, static penetration testing is usually used.

[0003] Static cone penetration testing (CPPT) is a mature and reliable method for geotechnical investigation of cohesive and sandy soils. It involves using a pressure device to press a probe with a probe tip into the test soil layer. By measuring the penetration resistance through a measurement system, certain basic physical and mechanical properties of the soil can be determined, such as the soil's deformation modulus and allowable bearing capacity. CPPT has become a popular in-situ testing and exploration method due to its advantages of continuous data measurement, high accuracy, strong repeatability, and low cost. Current national, industry, and local specifications and standards have established correlations between the static cone penetration resistance value qc and indicators such as the characteristic value of the foundation soil's bearing capacity fak, compression modulus Es, and shear wave velocity Vs.

[0004] Existing static cone penetration testing equipment can only perform static cone penetration and shear wave velocity data measurement, resulting in low efficiency of static cone penetration operations. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is that the existing static cone penetration test equipment can only perform static cone penetration and shear wave velocity data measurement, resulting in low efficiency of static cone penetration operation. Therefore, the present invention provides a soil in-situ testing device, system and method that can simultaneously perform static cone penetration, shear wave velocity data measurement and stress-strain data acquisition during soil expansion, thereby improving the efficiency of static cone penetration operation.

[0006] To address the above problems, the present invention provides an in-situ soil testing device, comprising: a soil expansion module, a shear wave velocity measurement module, and a static cone penetration test module connected sequentially from top to bottom;

[0007] The soil expansion module includes a support rod, an expansion membrane, an expansion pressure structure, and at least one set of lateral displacement sensing components. The expansion membrane is sleeved on the outside of the support rod, and the lateral displacement sensing components are disposed between the outer wall of the support rod and the expansion membrane. The expansion pressure structure is used to apply pressure to the expansion membrane to generate lateral stress and measure the lateral stress. The lateral displacement sensing components are used to monitor the lateral displacement value generated by the lateral stress on the expansion membrane.

[0008] As a preferred technical solution for an in-situ soil testing device, the expansion and pressure application structure includes a pressure application hole and a pressure controller. The pressure application hole is located inside the support rod, and the area between the side wall of the support rod and the expansion membrane communicates with the pressure application hole. The pressure controller is used to measure the pressure and volume within the area.

[0009] As a preferred technical solution for the in-situ soil testing device, the outer wall of the support rod is provided with multiple grooves, which are arranged along the axial direction of the support rod, and each groove is provided with a set of lateral displacement sensing components.

[0010] As a preferred technical solution for an in-situ soil testing device, the lateral displacement sensing component includes a rotating arm, a torsion spring pin, and a strain beam. The torsion spring pin is horizontally disposed in the groove. The middle part of the rotating arm is sleeved on the torsion spring pin. The upper end of the strain beam is cantilevered, and the lower end is fixed in the groove. The upper end of the rotating arm contacts the expansion membrane, and the lower end contacts the side of the strain beam opposite to the expansion membrane. Strain gauges are disposed on the strain beam.

[0011] As a preferred technical solution for the in-situ soil testing device, a step is provided in the groove, the lower end of the strain beam is fixed to the step, and a strain beam ball head column is provided at the position where the upper end of the strain beam contacts the rotating arm, and the spherical surface of the strain beam ball head column contacts the rotating arm.

[0012] As a preferred technical solution for in-situ soil testing devices, the support rod is further provided with a wiring hole, the groove is connected to the wiring hole, and the wire of the strain gauge enters the wiring hole.

[0013] As a preferred technical solution for the in-situ soil testing device, a protective cover is provided on the side of the groove near the expansion membrane, and a gap is provided between the upper end of the protective cover and the groove wall. A rotating arm ball head column is provided on the side of the upper end of the rotating arm facing the expansion membrane, and the spherical surface of the rotating arm ball head column contacts the expansion membrane through the gap.

[0014] As a preferred technical solution for the in-situ soil testing device, the soil expansion module is provided with an upper fixing ring at its upper end and a lower fixing ring at its lower end. The inner holes of the upper fixing ring and the lower fixing ring are stepped holes. The large-diameter section of the stepped hole is connected to the outer surface of the expansion membrane, and the small-diameter section of the stepped hole is connected to the outer surface of the support rod.

[0015] A soil in-situ testing system includes a host computer, a shear wave controller, a soil expansion controller, and the aforementioned soil in-situ testing device. The signal output terminal of the host computer is connected to the signal input terminals of the soil expansion controller and the shear wave controller, respectively. The signal output terminal of the shear wave controller is electrically connected to the signal input terminal of the shear wave velocity measurement module of the soil in-situ testing device, and the signal output terminal of the soil expansion controller is electrically connected to the signal input terminal of the soil expansion module of the soil in-situ testing device.

[0016] An in-situ soil testing method, employing the system described above, includes the following steps:

[0017] The in-situ soil testing device is driven to a predetermined depth. During the driving process, data is collected through the static cone penetration module. The data includes cone tip resistance, sidewall friction, pore water pressure, and probe tilt.

[0018] Start the shear wave controller, which controls the shear wave velocity measurement module to collect shear wave velocity data of the soil before deformation;

[0019] The soil expansion controller is activated, which controls the expansion and pressure application structure in the soil expansion module to collect the pressure of the soil's lateral expansion and controls the lateral displacement sensing component to collect the displacement of the soil's lateral expansion.

[0020] Restart the shear wave controller and collect shear wave velocity data of the soil after deformation through the shear wave velocity measurement module;

[0021] The in-situ soil testing device is then penetrated into the next predetermined stratum, and the above steps are repeated.

[0022] The test is complete, and the in-situ soil testing device is retrieved.

[0023] The technical solution of this invention has the following advantages:

[0024] 1. The in-situ soil testing device provided by the present invention comprises a soil expansion module, a shear wave velocity measurement module, and a static cone penetration test module. The soil expansion module includes a support rod, an expansion membrane, an expansion pressure structure, and at least one set of lateral displacement sensing components. The expansion pressure structure applies pressure to the expansion membrane to generate lateral stress and measures the lateral stress. The expansion membrane undergoes lateral displacement under the lateral stress, and the lateral displacement sensing components can monitor the lateral displacement value of the expansion membrane, thereby collecting stress-strain data during soil expansion. The shear wave velocity measurement module measures the shear wave velocity data, and the static cone penetration test module performs static cone penetration testing on the soil. Therefore, the in-situ soil testing device can simultaneously perform static cone penetration testing, shear wave velocity data measurement, and stress-strain data collection during soil expansion, improving the efficiency of static cone penetration testing operations.

[0025] 2. The soil in-situ testing device provided by this invention includes an expansion and pressure-applying structure comprising a pressure-applying hole and a pressure controller. The pressure-applying hole is located inside a support rod, and the area between the side wall of the support rod and the expansion membrane communicates with the pressure-applying hole. The pressure controller is used to measure the pressure and volume within the area. By providing the pressure-applying hole, liquid or gas can be injected into the area between the side wall of the support rod and the expansion membrane, causing the expansion membrane to expand outward and thus generating a lateral displacement value. By providing the pressure controller, the pressure and volume of the injected liquid or gas can be accurately measured, thereby accurately measuring the lateral stress and improving the accuracy of the measurement.

[0026] 3. The in-situ soil testing device provided by this invention includes a lateral displacement sensing component comprising a rotating arm, a torsion spring pin, and a strain beam. The torsion spring pin is horizontally positioned within a groove. The rotating arm is sleeved on the torsion spring pin at its midpoint. The upper end of the strain beam is cantilevered, while its lower end is fixed within the groove. The upper end of the rotating arm contacts the expansion membrane, and its lower end contacts the side of the strain beam opposite to the expansion membrane. Strain gauges are mounted on the strain beam. One end of the strain beam contacts the rotating wall, forming a lever structure. This lever structure, through the torsion spring pin, allows the rotating wall to rotate around the torsion spring pin, thereby generating a force on the strain beam in contact with the rotating arm. This causes mechanical deformation when the strain gauges on the strain beam contact the expansion membrane. By employing the lever structure, even minute positional changes at the upper end of the strain beam can be quickly and accurately transmitted to the lower end of the strain beam, and collected and transmitted via the strain gauges. This results in high detection accuracy, fast response, and stable loading, effectively ensuring the accuracy of the collected data.

[0027] 4. The in-situ soil testing device provided by this invention includes a protective cover on the side of the groove near the expansion membrane. A gap is provided between the upper end of the protective cover and the groove wall. A ball-head column of the rotating arm is provided on the upper end of the rotating arm facing the expansion membrane, and the spherical surface of the ball-head column contacts the expansion membrane through the gap. By providing a protective cover, the upper end of the cover leaves a gap, allowing the upper end of the rotating arm to make direct and full contact with the expansion membrane, improving the real-time performance and accuracy of the measurement. Furthermore, the lower end of the protective cover covers the strain beam and strain gauge, preventing them from directly contacting the expansion membrane and avoiding damage to the strain gauge during insertion into the soil. This improves the service life and measurement accuracy of the strain gauge, further ensuring the accuracy of the collected data.

[0028] 5. The in-situ soil testing device provided by this invention has an upper fixing ring at the upper end of the soil expansion module and a lower fixing ring at the lower end. The inner holes of both the upper and lower fixing rings are stepped holes. The larger diameter section of the stepped hole connects to the outer surface of the expansion membrane, and the smaller diameter section connects to the outer surface of the support rod. By setting the inner holes of the upper and lower fixing rings as stepped holes, sufficient space can be provided for the expansion of the membrane, better releasing the stress caused by expansion and achieving the goal of improving measurement accuracy.

[0029] 6. The soil in-situ testing system provided by the present invention, since it includes the above-mentioned soil in-situ testing device, has the beneficial effects of the soil in-situ testing device, which will not be elaborated here.

[0030] 7. The soil in-situ testing method provided by the present invention, since it includes the above-mentioned soil in-situ testing system, has the beneficial effects of the soil in-situ testing system, which will not be elaborated here. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the structure of the in-situ soil testing device of the present invention;

[0033] Figure 2 for Figure 1 Sectional view of AA in the middle;

[0034] Figure 3 for Figure 2 Enlarged view of point B in the middle;

[0035] Figure 4 This is a schematic diagram of the static cone penetration test module of the in-situ soil testing device of the present invention.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Soil Expansion Module; 101. Support Rod; 102. Expansion Membrane; 103. Wiring Hole; 104. Pressure Application Hole; 105. Groove; 106. Rotating Arm; 107. Torsion Spring Pin; 108. Strain Beam; 109. Protective Cover; 110. Upper Fixing Ring; 111. Lower Fixing Ring; 2. Shear Wave Velocity Measurement Module; 3. Static Cone Penetration Module; 301. AD Module; 302. Tilt Sensor; 303. Sidewall Friction Sensor; 304. Cone Tip Sensor; 305. Sidewall Friction Cylinder; 306. Pore Pressure Sensor; 307. Cone Tip. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] like Figure 1-4The diagram shows a preferred embodiment of the in-situ soil testing device of the present invention. This in-situ soil testing device can simultaneously perform static cone penetration testing, shear wave velocity data measurement, and stress-strain data acquisition during soil expansion, thereby improving the efficiency of static cone penetration testing operations.

[0043] The soil in-situ testing device of this embodiment includes: a soil expansion module 1, a shear wave velocity measurement module 2, and a static cone penetration test module 3 connected sequentially from top to bottom; the soil expansion module 1 includes a support rod 101, an expansion membrane 102, an expansion pressure structure, and at least one set of lateral displacement sensing components. The expansion membrane 102 is sleeved on the outside of the support rod 101. The lateral displacement sensing components are disposed between the outer wall of the support rod 101 and the expansion membrane 102. The expansion pressure structure is used to apply pressure to the expansion membrane 102 to generate lateral stress and measure the lateral stress. The lateral displacement sensing components are used to monitor the lateral displacement value generated by the lateral stress on the expansion membrane 102.

[0044] The in-situ soil testing device in this embodiment also includes a hollow sleeve. The soil expansion module 1, shear wave velocity measurement module 2, and static cone penetration test module 3 are all arranged axially inside the sleeve. The sleeve can protect the soil expansion module 1, shear wave velocity measurement module 2, and static cone penetration test module 3, preventing them from being contaminated by the soil and improving their service life and measurement accuracy.

[0045] The aforementioned in-situ soil testing device comprises a soil expansion module 1, a shear wave velocity measurement module 2, and a static cone penetration test module 3. The soil expansion module 1 includes a support rod 101, an expansion membrane 102, an expansion pressure structure, and at least one set of lateral displacement sensing components. The expansion pressure structure applies pressure to the expansion membrane 102 to generate lateral stress and measures this lateral stress. The expansion membrane 102 undergoes lateral displacement under this lateral stress, and the lateral displacement sensing components can monitor the lateral displacement value of the expansion membrane 102, thereby collecting stress-strain data during soil expansion. The shear wave velocity measurement module 2 measures the shear wave velocity data, and the static cone penetration test module 3 performs static cone penetration testing on the soil. Therefore, this in-situ soil testing device can simultaneously perform static cone penetration testing, shear wave velocity data measurement, and stress-strain data collection during soil expansion, improving the efficiency of static cone penetration testing operations.

[0046] In a preferred embodiment, the expansion and pressurization structure includes a pressure port 104 and a pressure controller. The pressure port 104 is disposed inside the support rod 101, and the area between the side wall of the support rod 101 and the expansion membrane 102 communicates with the pressure port 104. The pressure controller is used to measure the pressure and volume within the area. Specifically, as... Figure 2 and 3As shown, the pressure hole 104 is arranged axially along the support rod 101. The pressure hole 104 is a blind hole, and a through hole is formed on the lower side wall of the pressure hole 104. This through hole connects the pressure hole 104 with the area between the side wall of the support rod 101 and the expansion membrane 102, allowing liquid or gas to be injected into the area between the side wall of the support rod 101 and the expansion membrane 102 through the pressure hole 104, causing the expansion membrane 102 to expand and deform outward, i.e., generating lateral stress. In this embodiment, the pressure hole 104 is a hydraulic hole, through which hydraulic oil is injected between the side wall of the support rod 101 and the expansion membrane 102, causing the expansion membrane 102 to expand and deform outward, generating lateral stress. The pressure controller includes a spiral pump controlled by a microprocessor. The pump is connected to the hydraulic port for precise measurement of liquid pressure and volume changes. In independent working mode, it can function as a constant pressure source, replacing conventional indoor pressure sources such as mercury columns, air compressors, oil pumps, and net load devices. It can also function as a volume change indicator with a resolution of up to 1 mm³. During measurement, the microprocessor controls the screw pump to inject hydraulic oil into the hydraulic port. The hydraulic oil causes the expansion membrane 102 to expand and deform outward, generating lateral stress. This lateral stress is transmitted to the microprocessor through the screw pump, thereby obtaining the lateral stress of the measured soil. By setting a pressure controller, the pressure and volume of the injected liquid or gas can be precisely measured, thus accurately measuring the lateral stress and improving the accuracy of the measurement.

[0047] It should be noted that the injected liquid can also be water, oil or other liquids. In addition, the pressure hole 104 can also be a gas pressure hole, through which gas can be injected to make the expansion membrane 102 expand outward.

[0048] In a preferred embodiment, the outer wall of the support rod 101 is provided with a plurality of grooves 105, which are arranged along the axial direction of the support rod 101. Each groove 105 is provided with a set of lateral displacement sensing components. Specifically, as shown in the figure... Figure 2 and 3 As shown, multiple grooves 105 are provided on the side of the support rod 101 near the hydraulic hole, and the multiple grooves 105 are distributed at intervals along the axial direction of the support rod 101. By providing a set of lateral displacement sensing components in each groove 105, stress-strain data at different soil depths can be measured simultaneously when the soil expansion module 1 penetrates the soil, thereby improving work efficiency.

[0049] In a preferred embodiment, the lateral displacement sensing assembly includes a rotating arm 106, a torsion spring pin 107, and a strain beam 108. The torsion spring pin 107 is horizontally disposed within a groove 105. The rotating arm 106 is sleeved on the torsion spring pin 107 at its middle portion. The upper end of the strain beam 108 is cantilevered, and the lower end is fixed within the groove 105. The upper end of the rotating arm 106 contacts the expansion membrane 102, and the lower end contacts the side of the strain beam 108 facing away from the expansion membrane 102. Strain gauges are disposed on the strain beam 108. Specifically, as shown... Figure 2 and 3 As shown, the torsion spring pin 107 is horizontally disposed within the groove 105, with both ends welded to the sidewalls of the groove 105. A through hole is provided in the middle of the rotating arm 106, which is sleeved onto the torsion spring pin 107, allowing the rotating arm 106 to rotate around the torsion spring pin 107. A step is provided within the groove 105, and the lower end of the strain beam 108 is fixed to the step. Because the lower end of the strain beam 108 is fixed, the upper end of the strain beam 108 is in a longitudinal cantilever state. A ball-head post of the strain beam 108 is provided at the contact point between the upper end of the strain beam 108 and the rotating arm 106. The spherical surface of the ball-head post of the strain beam 108 contacts the spherical surface of the ball-head post of the rotating arm 106. A strain gauge is provided on the side of the beam 108 facing the expansion membrane 102. One end of the strain beam 108 contacts the rotating wall and forms a lever structure. The lever structure is provided with a torsion spring pin 107, which allows the rotating wall to rotate around the torsion spring pin 107. This causes the strain beam 108, which is in contact with the rotating arm 106, to generate a force. When the strain gauge on the strain beam 108 contacts the expansion membrane 102, it causes mechanical deformation. By setting up the lever structure, even if there is a small positional change at the upper end of the strain beam 108, it can be quickly and accurately transmitted to the lower end of the strain beam 108 and collected and transmitted by the strain gauge. The detection accuracy is high, the response is fast, and the loading is stable, which can effectively ensure the accuracy of the collected data.

[0050] In a preferred embodiment, the support rod 101 is further provided with a wiring hole 103, and the groove 105 communicates with the wiring hole 103, through which the strain gauge wires enter. Specifically, as shown... Figure 2 and 3 As shown, the wiring hole 103 is arranged along the axial direction of the support rod 101. The bottom of the groove 105 is provided with a through hole that communicates with the wiring hole 103. The strain gauge is guided through the through hole into the wiring hole 103. By setting the wiring hole 103, the wiring is uniformly arranged, which saves the internal space of the support rod 101 and facilitates assembly and maintenance.

[0051] In a preferred embodiment, a protective cover 109 is provided on the side of the groove 105 near the expansion membrane 102. A gap is provided between the upper end of the protective cover 109 and the groove wall of the groove 105. A ball-head post of the rotating arm 106 is provided on the side of the upper end of the rotating arm 106 facing the expansion membrane 102. The spherical surface of the ball-head post of the rotating arm 106 contacts the expansion membrane 102 through the gap. Figure 3 As shown, the protective cover 109 is fixedly installed on the side of the groove 105 near the expansion membrane 102. The two ends of the rotating arm 106 are respectively provided with rotating arm ball joints protruding towards the expansion membrane 102. The rotating arm ball joints at the upper end of the rotating arm 106 contact the expansion membrane 102 through the gap at the upper end of the protective cover 109. By setting the protective cover 109, the upper end of the protective cover 109 leaves a gap so that the upper end of the rotating arm 106 can directly and fully contact the expansion membrane 102, improving the real-time performance and accuracy of the measurement. In addition, the lower end of the protective cover 109 covers the strain beam 108 and the strain gauge, so that they do not directly contact the expansion membrane 102, avoiding damage to the strain gauge during the insertion into the soil, improving the service life and measurement accuracy of the strain gauge, and further ensuring the accuracy of the collected data.

[0052] In a preferred embodiment, the soil expansion module 1 has an upper fixing ring 110 at its upper end and a lower fixing ring 111 at its lower end. The inner holes of both the upper fixing ring 110 and the lower fixing ring 111 are stepped holes. The larger diameter section of the stepped hole is connected to the outer surface of the expansion membrane 102, and the smaller diameter section is connected to the outer surface of the support rod 101. Specifically, as shown... Figure 2 As shown, the expansion membrane 102 is made of nitrile rubber with a hardness of 90. The upper and lower ends of the expansion membrane 102 are fixedly connected to the upper fixing ring 110 and the lower fixing ring 111 respectively through vulcanization treatment. Vulcanization treatment refers to the process of adding sulfur, carbon black, etc. to raw rubber and heating it under high pressure to turn it into vulcanized rubber. After vulcanization treatment, the inherent defects of the rubber, such as low strength, low elasticity, cold hardening and hot sticking, and easy aging, are changed. Its wear resistance, swelling resistance, and heat resistance are significantly improved, expanding its application range. The inner holes of the upper fixing ring 110 and the lower fixing ring 111 are both stepped holes. The small-diameter section of the upper fixing ring 110 and the lower fixing ring 111 is connected to the outer wall of the support rod 101, and the large-diameter section is connected to the outer wall of the expansion membrane 102. By setting the inner holes of the upper fixing ring 110 and the lower fixing ring 111 as stepped holes, sufficient space can be provided for the expansion of the expansion membrane 102, which can better release the stress brought about by the expansion and achieve the purpose of improving measurement accuracy.

[0053] In this embodiment, the static cone penetration module 3 is installed below the shear wave velocity measurement module 2, as shown below. Figure 4As shown, the shear wave velocity measurement module 2 includes a shear wave velocity sensor, and the static cone penetration module 3 includes an AD module 301, an inclination sensor 302, a sidewall friction sensor 303, a cone tip sensor 304, a sidewall friction cylinder 305, a pore pressure sensor 306, and a cone tip 307. The cone tip 307 is installed at the bottom of the static cone penetration module 3, and is connected to the cone tip sensor 304 above it. The pore pressure sensor 306 is installed inside the cone tip sensor 304 and communicates with the outside through a small hole. The sidewall friction sensor 303 is installed outside the cone tip sensor 304, and the sidewall friction cylinder 305 is installed outside the sidewall friction sensor 303. The step inside the sidewall friction cylinder 305 rests on the step outside the sidewall friction sensor 303. The AD module 301 and the inclination sensor 302 are located on the upper part of the static cone penetration module 3 and are protected by a sleeve. During static cone penetration testing, the resistance of the cone tip 307 is transmitted to the cone tip sensor 304 and measured. Pore water pressure is transmitted through a small hole to the pore pressure sensor 306 and measured. Sidewall friction is transmitted through the sidewall friction cylinder 305 to the sidewall friction sensor 303 and measured. The tilt angle of the integrated in-situ soil expansion testing device is measured by the tilt sensor 302. The measured cone tip resistance, sidewall friction, pore water pressure, and tilt data are converted from analog signals to digital signals by the AD module 301 and output to the host computer. Since the shear wave velocity measurement module 2 and the static cone penetration testing module 3 are existing technologies, they will not be described in detail here.

[0054] This embodiment also provides an in-situ soil testing system, including a host computer, a shear wave controller, a soil expansion controller, and the aforementioned in-situ soil testing device. The signal output terminal of the host computer is connected to the signal input terminals of the soil expansion controller and the shear wave controller, respectively. The signal output terminal of the shear wave controller is electrically connected to the signal input terminal of the shear wave velocity measurement module 2 of the in-situ soil testing device, and the signal output terminal of the soil expansion controller is electrically connected to the signal input terminal of the soil expansion module 1 of the in-situ soil testing device. Specifically, the in-situ soil testing device penetrates to a predetermined depth. During the penetration process, data is collected through the static cone penetration test module 3. The shear wave controller controls the shear wave velocity measurement module 2 to collect soil shear wave velocity data. The soil expansion controller controls the expansion and pressure application structure in the soil expansion module 1 to collect the pressure of the soil's lateral expansion and controls the lateral displacement sensing component to collect the displacement of the soil's lateral expansion. This in-situ soil testing system can simultaneously perform static cone penetration testing, shear wave velocity data measurement, and stress-strain data collection during soil expansion, improving the efficiency of static cone penetration testing operations.

[0055] This embodiment also provides an in-situ soil testing method, using the system described above, which includes the following steps:

[0056] The in-situ soil testing device is driven to a predetermined depth. During the driving process, data is collected through the static cone penetration module 3. The data includes cone tip resistance, sidewall friction, pore water pressure, and probe tilt.

[0057] Start the shear wave controller, which controls the shear wave velocity measurement module 2 to collect shear wave velocity data of the soil before deformation.

[0058] Start the soil expansion controller. The soil expansion controller controls the expansion and pressure application structure in the soil expansion module 1 to collect the pressure of the soil expansion in the lateral direction, and controls the lateral displacement sensing component to collect the displacement of the soil expansion in the lateral direction.

[0059] Restart the shear wave controller and collect shear wave velocity data of the soil after deformation through the shear wave velocity measurement module 2;

[0060] The in-situ soil testing device is then penetrated into the next predetermined stratum, and the above steps are repeated.

[0061] The test is complete, and the in-situ soil testing device is retrieved.

[0062] Specifically, the soil in-situ testing device is first driven to a predetermined depth. During the driving process, the static penetration module 3 collects data on the resistance of the cone tip 307, the friction of the side wall, the pore water pressure, and the tilt. The analog signal is converted into a digital signal by the AD module 301 and then output to the host computer.

[0063] Then, the shear wave controller is started. The shear wave controller controls the shear wave velocity sensor to collect the shear wave velocity data of the soil before deformation and transmits the shear wave velocity data before deformation to the host computer.

[0064] Simultaneously, the soil expansion controller is activated, and the host computer controls the screw pump to inject hydraulic oil into the area between the expansion membrane 102 and the support rod 101 through the hydraulic port. Under the action of the hydraulic oil, the expansion membrane 102 gradually expands outward. When the soil expansion controller controls the hydraulic oil to flow back, the expansion membrane 102 gradually retracts inward. The screw pump can accurately measure the pressure and volume of the hydraulic oil injected between the expansion membrane 102 and the support rod 101, that is, it can accurately measure the lateral stress data of the expansion membrane 102 and transmit this lateral stress data to the host computer. In the free state, the expansion membrane 102 and the rotating arm 101... 6. Under the action of the torsion spring pin 107, the strain beam 108 deforms and adheres tightly to the lower end of the rotating arm 106. When the expansion membrane 102 expands or contracts, the contact position between the upper end of the rotating arm 106 and the expansion membrane 102 will change, causing the pressure value applied by the lower end of the rotating arm 106 to the strain beam 108 to change. The change in pressure on the strain beam 108 by the rotating arm 106 is collected by the strain gauge and transmitted to the host computer. By measuring the strain data of the strain beam 108, the lateral displacement data can be obtained. Different lateral stresses correspond to different lateral displacements, and the stress-strain curve of the soil can be obtained.

[0065] The shear wave controller is then activated. The shear wave controller controls the shear wave velocity sensor to collect shear wave velocity data after soil deformation and transmits the deformed shear wave velocity data to the host computer.

[0066] The in-situ soil testing device is then penetrated into the next predetermined stratum, and the above steps are repeated to collect static cone penetration test data, shear wave velocity data, and stress-strain data during soil expansion at different strata. The data is then transmitted to the host computer. Once the test is completed, the in-situ soil testing device is retrieved, thus completing the in-situ soil test.

[0067] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A soil in-situ testing device, characterized in that, include: The soil expansion module (1), shear wave velocity measurement module (2), and static cone penetration module (3) are connected sequentially from top to bottom. The soil expansion module (1) includes a support rod (101), an expansion membrane (102), an expansion pressure structure, and at least one set of lateral displacement sensing components. The expansion membrane (102) is sleeved on the outside of the support rod (101). The lateral displacement sensing components are disposed between the outer wall of the support rod (101) and the expansion membrane (102). The expansion pressure structure is used to apply pressure to the expansion membrane (102) to generate lateral stress and measure the lateral stress. The lateral displacement sensing components are used to monitor the lateral displacement value generated by the lateral stress on the expansion membrane (102). The outer wall of the support rod (101) is provided with a plurality of grooves (105), the plurality of grooves (105) are arranged along the axial direction of the support rod (101), and a set of the lateral displacement sensing components are provided in each groove (105). The lateral displacement sensing component includes a rotating arm (106), a torsion spring pin (107), and a strain beam (108). The torsion spring pin (107) is horizontally disposed in the groove (105). The middle part of the rotating arm (106) is sleeved on the torsion spring pin (107). The upper end of the strain beam (108) is in a cantilever state, and the lower end is fixed in the groove (105). The upper end of the rotating arm (106) contacts the expansion membrane (102), and the lower end contacts the side of the strain beam (108) facing away from the expansion membrane (102). Strain gauges are disposed on the strain beam (108). A step is provided in the groove (105), the lower end of the strain beam (108) is fixed to the step, and a strain beam ball head column is provided at the position where the upper end of the strain beam (108) contacts the rotating arm (106), and the spherical surface of the strain beam ball head column contacts the rotating arm (106). The expansion and pressure-applying structure includes a pressure-applying hole (104) and a pressure-applying controller. The pressure-applying hole (104) is disposed inside the support rod (101). The area between the side wall of the support rod (101) and the expansion membrane (102) communicates with the pressure-applying hole (104). The pressure-applying controller is used to measure the pressure and volume in the area.

2. The in-situ soil testing device according to claim 1, characterized in that, The support rod (101) is also provided with a wiring hole (103), the groove (105) is connected to the wiring hole (103), and the wire of the strain gauge enters the wiring hole (103).

3. The in-situ soil testing device according to claim 2, characterized in that, A protective cover (109) is provided on the side of the groove (105) near the expansion membrane (102). A gap is provided between the upper end of the protective cover (109) and the groove wall of the groove (105). A rotating arm ball head column is provided on the side of the upper end of the rotating arm (106) facing the expansion membrane (102). The spherical surface of the rotating arm ball head column contacts the expansion membrane (102) through the gap.

4. The in-situ soil testing device according to any one of claims 1-3, characterized in that, The soil expansion module (1) is provided with an upper fixing ring (110) at its upper end and a lower fixing ring (111) at its lower end. The inner holes of the upper fixing ring (110) and the lower fixing ring (111) are both stepped holes. The large-diameter hole section of the stepped hole is connected to the outer side of the expansion membrane (102), and the small-diameter hole section of the stepped hole is connected to the outer side of the support rod (101).

5. A soil in-situ testing system, characterized in that, The device includes a host computer, a shear wave controller, a soil expansion controller, and the soil in-situ testing device according to any one of claims 1-4. The signal output terminal of the host computer is connected to the signal input terminals of the soil expansion controller and the shear wave controller, respectively. The signal output terminal of the shear wave controller is electrically connected to the signal input terminal of the shear wave velocity measurement module (2) of the soil in-situ testing device, and the signal output terminal of the soil expansion controller is electrically connected to the signal input terminal of the soil expansion module (1) of the soil in-situ testing device.

6. A method for in-situ soil testing, characterized in that, The system as described in claim 5 includes the following steps: The soil in-situ testing device is driven to a predetermined depth. During the driving process, data is collected by the static cone penetration module (3). The data includes cone tip resistance, sidewall friction, pore water pressure and probe tilt. Start the shear wave controller, which controls the shear wave velocity measurement module (2) to collect shear wave velocity data before soil deformation; Start the soil expansion controller, which controls the expansion pressure structure in the soil expansion module (1) to collect the pressure of the soil expansion in the lateral direction, and controls the lateral displacement sensing component to collect the displacement of the soil expansion in the lateral direction. Restart the shear wave controller and collect the shear wave velocity data of the soil after deformation through the shear wave velocity measurement module (2); The in-situ soil testing device is then penetrated into the next predetermined stratum, and the above steps are repeated. The test is complete, and the in-situ soil testing device is retrieved.

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