A testing system and method for thermo-setting and shear properties of non-displacement pile contact interfaces

Abstract

This invention provides a system and method for testing the thermosetting and shear properties of the contact interface of non-displacement piles. The thermosetting and shear property testing system includes: a pressure-filtering shear container, a pressurized grouting and constant-pressure device, a pressurization and temperature control device, and a shear loading device. The pressure-filtering shear container includes a left container body and a right container body, which are joined together and sealed by a connecting belt to form a pressure-filtering shear chamber. The pressurized grouting and constant-pressure device includes a grout storage container and a pressure conveyor. The grout storage container is connected to the pressure-filtering shear chamber, and the pressure conveyor is connected to the grout storage container. The pressurization and temperature control device is located on the outside of the pressure-filtering shear container near the left container body. The shear loading device is located outside the pressure-filtering shear container. This invention provides a reliable experimental means for studying the performance of non-displacement piles in practical applications, improving the safety and durability of buildings.

Description

Technical Field

[0001] This invention relates to the field of pile foundation engineering technology, and in particular to a system and method for testing the thermo-firm and shear properties of the contact interface of a non-displacement pile. Background Technology

[0002] As an innovative structure integrating ground source heat pump technology with traditional pile foundations, energy piles are receiving increasing attention and application. They utilize geothermal resources in an environmentally friendly and efficient manner to achieve building heating and cooling. In the construction field, the application of energy piles has shown great potential in energy conservation, environmental protection, and improving building energy efficiency. However, during the thermal cycle of energy piles, the pile body and surrounding soil of non-displacement energy piles will undergo thermal expansion and contraction. Under the action of temperature stress, the surrounding soil may also undergo thermal consolidation deformation. This has a significant impact on the bearing capacity of non-displacement energy piles based on pile-side grouting (such as drilling-while-conducting piles and drilling-while-conducting energy piles). Therefore, it is crucial to explore the influence of heat exchange of energy piles on the consolidation deformation of the pile-side soil.

[0003] Grouting-side non-displacement piles, exemplified by drilling-while-conduit energy piles, exhibit a typical "pile-grout-soil" contact interface. Thermal consolidation of the soil along the pile surface alters the structure and stress characteristics of this interface, significantly impacting the pile's skin friction. Effective testing of the "pile-grout-soil" contact interface is crucial for calculating the bearing capacity of drilling-while-conduit energy piles. However, currently, there is no dedicated testing equipment to perform performance tests on the shear characteristics of the "pile-grout-soil" contact interface in non-displacement piles such as drilling-while-conduit energy piles. This lack of reliable experimental foundation for the practical application of non-displacement piles hinders their further promotion in real-world applications. Summary of the Invention

[0004] This invention provides a testing system and method for the thermo-firm and shear properties of the contact interface of non-displacement piles, which addresses the problems existing in the prior art. It can comprehensively simulate the thermo-firm and shear properties of the "pile-grout-soil" contact interface in actual engineering, providing a reliable experimental means for studying the performance of non-displacement piles in practical applications. Furthermore, by studying the thermo-firm and shear properties of the pile-grout-soil contact interface, the design and construction process of pile foundations can be optimized, thereby improving the safety and durability of buildings.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect, the present invention provides a testing system for the thermo-firm and shear properties of the contact interface of a non-displacement pile, comprising:

[0007] The filter press shearing container includes a left container body for holding concrete and a right container body for holding soil. The left and right container bodies are joined together and sealed by a connecting belt to form a filter press shearing chamber. The left container body is provided with an S-shaped water pipe.

[0008] A pressurized grouting and constant pressure device includes a slurry storage container and a pressure conveyor. The slurry storage container is connected to the pressure filter shearing chamber. The pressure conveyor is connected to the slurry storage container and is used to convey air and slurry in the slurry storage container to the pressure filter shearing chamber.

[0009] A pressurizing and temperature control device is installed on the outside of the filter press shear container near the left container body. The pressurizing and temperature control device is connected to the inlet and outlet of the S-shaped water pipe inside the left container body. The inlet and outlet of the S-shaped water pipe are both located on the top wall of the left container body.

[0010] A shear loading device is disposed outside the filter press shear container and is used to apply tangential and normal forces to the right container body and monitor the displacement of the right container body along the directions of the tangential and normal forces.

[0011] Furthermore, the left container body has multiple first temperature sensors at its interface, which are fixedly mounted on the first support frame at equal intervals; the right container body has multiple pore pressure sensors fixedly mounted on the second support frame at its interface via a second support frame at equal intervals; the right container body has a displacement monitoring element, a first pressure monitoring element, and a drain hole on its bottom wall away from the left container body. The displacement monitoring element is used to monitor the displacement of the soil in the filter shear chamber, the first pressure monitoring element is used to monitor the pressure of the soil in the right container body on the container wall, and the drain hole is used for slurry collection and detection.

[0012] Furthermore, the slurry storage container is equipped with a second pressure monitoring element and a regulating valve. The regulating valve is located on the connection channel between the slurry storage container and the pressure conveyor, and is used to adjust the pressure inside the pressurized grouting and constant pressure device.

[0013] Furthermore, the pressurization and temperature control device includes a water storage container and a connecting water pipe. The water storage container is equipped with a heating structure. The connecting water pipe passes through the water storage container. The heating structure is located on the outer wall of the connecting water pipe inside the water storage container. A circulating water pump is installed on the connecting water pipe inside the water storage container. The two ends of the connecting water pipe are respectively connected to the inlet and outlet of the S-shaped water pipe to form a closed circulating water circuit.

[0014] Furthermore, the shear loading device includes a fixed frame, a tangential force loading structure, and a normal force loading structure, both of which are mounted on the fixed frame. The tangential force loading structure abuts against one side wall of the right container body, and this side wall is also provided with a tangential force sensor and a shear displacement sensor. The normal force loading structure abuts against the bottom wall of the right container body away from the left container body, and this bottom wall is also provided with a normal force sensor and a normal displacement sensor. The top of the fixed frame is connected and fixed to the top of the left container body through a connecting frame. The fixed frame is also provided with multiple fixing posts, which abut against the side wall of the left container body respectively.

[0015] Furthermore, the top of the pressure filter shear chamber has multiple through holes, including at least a first through hole, a second through hole, and a third through hole. The first through hole is used to place the input pipe of the pressure conveyor; the second through hole is used for venting during grouting or for pressure filtration during the pressure conveyor; and the third through hole is used to place a pressure gauge.

[0016] Furthermore, the thermosetting and shear property testing system also includes a PIV monitoring device, which is fixed to the outside of the filter press shear container. The camera of the PIV monitoring device is aimed at the entire filter press shear container to observe the internal changes of the filter press shear container.

[0017] Furthermore, multiple displacement monitoring elements are provided, each of which includes an LVDT displacement meter and a sensing plate. The sensing plate is parallel to the side wall of the right container body and is disposed inside the right container body. The sensing plate is connected to the bottom of the LVDT displacement meter.

[0018] Secondly, the present invention provides a method for testing the thermo-firm and shear properties of the contact interface of a non-displacement pile, based on the above-mentioned thermo-firm and shear property testing system, comprising the following steps:

[0019] Step S01: Fabricate the main body of the left container, and install the S-shaped water pipe and the first sensor on the main body of the left container;

[0020] Step S02: After wrapping the first connecting strip around the interface of the left container body once, fix it and seal the connection.

[0021] Step S03: With the joint of the left container body facing upward, fill the left container body with concrete until it is flush with the joint of the left container body, and cure it at 25°C for 28 days.

[0022] Step S04: Fabricate the right container body, install the displacement monitoring element, the first pressure monitoring element, and the pore pressure sensor on the right container body, fix the second connecting strap around the joint of the right container body once and seal the connection; with the joint of the right container body facing upwards, fill the right container body with soil, and use a heavy hammer to compact the soil during the filling process so that the soil inside the right container body is level with the joint of the right container body; at the same time, open the valve at the drain hole during the compaction process to receive the seepage water in the soil;

[0023] Step S05: Align the left container body after curing with the right container body after backfilling at the interface. Connect the two ends of the third connecting strip to the first and second connecting strips respectively with bolts to achieve the docking connection between the left and right container bodies. The connection of the connecting strips forms a pressure filter shearing chamber. Set an input hole at the top of the pressure filter shearing chamber for passing through the input pipe of the pressure grouting and constant pressure device and connect it to the input pipe of the pressure grouting and constant pressure device. Set an exhaust hole for venting or for use when the input pipe of the pressure grouting and constant pressure device is used for pressure filtration. Set a pressure gauge at the top of the pressure filter shearing chamber.

[0024] Step S06: Before grouting, turn on the PIV monitoring device, point the camera of the PIV monitoring device at the entire filter press shear container, and fix the position of the filter press shear container and the camera; grouting is carried out, the vent is opened, and the grout containing pigment in the grout storage container of the pressurized grouting and constant pressure device is injected into the filter press shear chamber through the pressure conveyor. During the grouting process, the displacement deformation of the displacement detection element, the change of pore pressure of the pore pressure sensor, and the change of soil pressure before and after grouting of the first pressure monitoring element are recorded. At the same time, the seepage water of the soil under the action of grouting is collected through the drainage hole at the right container body.

[0025] Step S07: After the filter press shear chamber is filled with grout, the vent hole is sealed to seal the filter press shear chamber. Constant pressure is applied to the grouting chamber through a pressure conveyor, and a pressure gauge is used to monitor the pressure in real time to cure the newly injected grout under constant pressure. At the same time, the seepage water in the soil is collected through the drain hole at the main body of the right container and compared with the chemical substances contained in the seepage water of the soil before grouting.

[0026] Step S08: After the grout has completely solidified, a pile-grout-soil model test block is obtained;

[0027] Prepare five identical pile-grout-soil model test blocks according to steps S01-S07;

[0028] Remove the connecting strip and connect the inlet and outlet of the S-shaped water pipe of the pile-grout-soil model test block to the pressurization and temperature control device. Water at 10℃, 20℃, 30℃, 40℃ and 50℃ is introduced into the five pile-grout-soil model test blocks respectively, and the water introduction time is 2 hours for each.

[0029] Step S09: Rotate the pile-grout-soil model test block so that the right container is at the bottom and vertically upward. Place the pile-grout-soil model test block inside the shear loading device, so that the tangential force loading structure abuts against the side wall of the right container body and the normal force loading structure abuts against the bottom of the right container body. The tangential force loading structure and the normal force loading structure provide tangential force and normal force, respectively. The PIV monitoring device records the failure process of the pile-grout-soil interface and the visual displacement of the pile or soil. The pore pressure sensor detects the pore pressure inside the soil. The first pressure monitoring element measures the change in pressure on the soil under the shear dilatation of the side soil when the pile-grout-soil is subjected to tangential force. The displacement monitoring element measures the displacement of the soil. At the same time, collect the seepage water in the soil and observe the seepage of the soil under the influence of tangential force.

[0030] Record the maximum shear strength of the pile-grout-soil model specimens after failure at five different temperatures and perform final analysis.

[0031] S10: After the pile-grout-soil model test block is destroyed, the soil part that has been contaminated with pigment is excavated, and the remaining uncontaminated part is retained to observe the penetration effect of the grout on the soil.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] The thermosetting and shear characteristic testing system of this invention, through the synergistic action of a pressure filter shear container, a pressurized grouting and constant pressure device, a pressurization and temperature control device, and a shear loading device, can comprehensively simulate the thermosetting and shear characteristics of the pile-grout-soil contact interface in actual engineering, providing a reliable experimental means for studying the performance of non-displacement piles in practical applications. Furthermore, by studying the thermosetting and shear characteristics of the pile-grout-soil contact interface, the design and construction process of pile foundations can be optimized, improving the safety and durability of buildings. This invention can collect data on various parameters, such as temperature, displacement, pressure, and pore water pressure, through various monitoring elements, providing rich data support for in-depth research on the characteristics of the pile-grout-soil contact interface.

[0034] Furthermore, the coordinated operation of all systems reduces human error during the experiment, improving efficiency and accuracy. The sealed connections and precise monitoring components ensure the stability and reliability of experimental conditions, guaranteeing accurate results. This technology can provide a scientific basis for the design, construction, and performance evaluation of non-displacement piles, contributing to improved application levels and market competitiveness of green energy utilization technologies such as energy piles. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of the left and right container bodies after docking in a specific embodiment of the thermosetting and shear property testing system of the present invention;

[0037] Figure 2 This is a schematic diagram of the main structure of the left container in a thermosetting and shear property testing system according to a specific embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the structure of the left container body after it is filled with concrete in a specific embodiment of the thermosetting and shear property testing system of the present invention.

[0039] Figure 4 This is a schematic diagram of the main structure of the right container in a thermosetting and shear property testing system according to a specific embodiment of the present invention;

[0040] Figure 5 This is a schematic diagram of the structure of the right container body after filling with soil in the thermosetting and shear property testing system of a specific embodiment of the present invention;

[0041] Figure 6 This is a schematic diagram of the grouting structure after the left and right container bodies are connected in a specific embodiment of the thermosetting and shear property testing system of the present invention;

[0042] Figure 7 This is a schematic diagram of the structure after grouting is completed in the thermosetting and shear property testing system of a specific embodiment of the present invention;

[0043] Figure 8 This is a schematic diagram of the connection structure between the left container body and the right container body in a perpendicular state and the pressurization and temperature control device in a specific embodiment of the thermosetting and shear property testing method of the present invention.

[0044] Figure 9 This is a schematic diagram of the connection structure between the pile-grout-soil model test block and the shear loading device in a specific embodiment of the present invention.

[0045] Wherein: 1. Left container body; 10. S-shaped water pipe; 101. Water inlet; 102. Water outlet; 11. First temperature sensor; 12. First support frame;

[0046] 2. Right container body; 20. Displacement monitoring element; 21. First pressure monitoring element; 22. Drain hole; 23. Pore pressure sensor; 24. Second support frame;

[0047] 3. Pressurized grouting and constant pressure device; 30. Grout storage container; 31. Pressure conveyor;

[0048] 4. Pressurization and temperature control device; 40. Water storage container; 41. Connecting water pipe; 42. Circulating water pump; 43. Heating structure;

[0049] 5. Shear loading device; 50. Fixing frame; 51. Tangential force loading structure; 52. Normal force loading structure; 53. Connecting frame; 54. Fixing column;

[0050] 61. First through hole; 62. Second through hole; 63. Third through hole;

[0051] 7. Slurry collection and detection device; 8. Pressure filter shear chamber 102. Detailed Implementation

[0052] 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.

[0053] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "top", "bottom", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and 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 limiting this invention.

[0054] This embodiment discloses a testing system and method for the thermo-firm and shear properties of the contact interface of a non-displacement pile, which is used to solve the problems existing in the prior art. This embodiment takes the "pile-grout-soil" contact interface of a non-displacement pile as an example, and the following is combined with the attached... Figure 1 To be continued Figure 9 The invention is described in detail with specific embodiments to comprehensively simulate the thermo-solid and shear characteristics of the pile-grout-soil contact interface in actual engineering, providing a reliable experimental means for studying the performance of non-displacement piles in practical applications; and by studying the thermo-solid and shear characteristics of the pile-grout-soil contact interface, the design and construction process of pile foundations can be optimized to improve the safety and durability of buildings.

[0055] On one hand, the present invention provides a thermosetting and shear characteristic testing system for the contact interface of a non-displacement pile, comprising: a pressure-filtering shear container, a pressurized grouting and constant pressure device 3, a pressurization and temperature control device 4, and a shear loading device 5. The pressure-filtering shear container includes a left container body 1 for holding concrete and a right container body 2 for holding soil. The left container body 1 and the right container body 2 are joined together and sealed by a connecting strip to form a pressure-filtering shear chamber for holding grout. An S-shaped water pipe 10 is installed inside the left container body 1, and the S-shaped water pipe 10 is fixed inside the left container body by multiple fixing brackets. The inlet 101 and outlet 102 of the S-shaped water pipe 10 are both located on the top wall of the left container body 1. The S-shaped water pipe 10 is used to hold media at different temperatures to verify the effect of different temperatures on the pile body inside the left container body 1.

[0056] Multiple first temperature sensors 11 are installed at the interface of the left container body 1. These sensors are mounted on the same first support frame 12 and fixed to the interface of the left container body 1 via the first support frame 12. In this embodiment, the first temperature sensors 11 are positioned beside the S-shaped water pipe 10, with the first support frame 12 parallel to the axis of the S-shaped water pipe 10. Three first temperature sensors 11 are evenly spaced to monitor the temperature of the concrete inside the left container body 1. Using multiple first temperature sensors 11 allows for a more comprehensive understanding of the concrete temperature at different heights within the left container body 1. Since the concrete may exhibit uneven temperature distribution within the container, multiple first temperature sensors 11 can capture temperature changes at different heights, avoiding the inaccurate local temperature monitoring that might occur with only one first temperature sensor 11. Furthermore, the temperature change trend of the concrete at different heights over time can be observed, which is very helpful for studying the temperature conduction and heat diffusion characteristics of concrete during heat exchange, providing more detailed data for a deeper understanding of the performance changes of the pile under different temperature conditions.

[0057] In this embodiment, the connecting water pipe 41 is a stainless steel pipe with a diameter of 2cm, which has good heat transfer effect. The circulating water pump 42 is a high-power, high-flow-rate circulating water pump with a power of 200W and a flow rate of 2m3 / h. The circulating water pump 42 can ensure that the water flow rate reaches 5cm / s, thereby achieving a good heat transfer or cooling effect on the thermal consolidation effect inside the pile body in the left container body 1. Multiple pore pressure sensors 23 are provided at the interface of the right container body 2; on the bottom wall of the right container body 2 away from the left container body 1, there are displacement monitoring elements 20 for monitoring the displacement of the soil in the pressure shear chamber, a first pressure monitoring element 21 for monitoring the pressure of the soil in the right container body 2 on the container wall, and a drain hole 22 for slurry collection and detection. A slurry collection and detection device 7 is installed at the drain hole 22 of the right container body 2. The slurry collection and detection device 7 is a steel funnel, which is fixed at the drain hole 22 by bolts, etc., and is used to collect seepage water in the soil. A valve is installed at the bottom of the steel funnel to control the outflow of water stored within. Simultaneously, a flexible water pipe guides the water from the funnel to a water quality analyzer. The analyzer can monitor the substances contained in the water after compaction of natural soil, as well as the newly formed mixed solution after grout injection. By comparing the exudate solutions before and after compaction of the natural soil, the types and contents of chemical substances can be analyzed. This is of great significance for studying the interaction between grout and soil, changes in the physicochemical properties of the soil, and the performance of the pile-grout-soil interface.

[0058] In this embodiment, multiple displacement monitoring elements 20 are provided. Each displacement monitoring element 20 includes an LVDT displacement meter and a sensing element. The sensing element is parallel to the side wall of the right container body 2 and is disposed inside the right container body 2. The sensing element is connected to the bottom of the LVDT displacement meter. In this embodiment, three small circular holes with a diameter of about 5 mm are reserved on the side wall of the right container body 2 for placing the LVDT displacement meter. The bottom of the LVDT displacement meter is inserted into the side wall of the right container body 2, and the sensing element is connected to the bottom of the LVDT displacement meter. The displacement monitoring elements 20 can simultaneously monitor the displacement of the soil in the filter shear chamber at different height positions. Since the displacement of the soil under pressure and other conditions may vary at different heights, multiple displacement monitoring elements 20 can more comprehensively reflect the overall displacement change of the soil and avoid the limitations of single-position monitoring. The three small circular holes are equally spaced along the height direction of the right container body 2. The equally spaced arrangement makes the monitoring data more representative and helps to analyze the distribution pattern of soil displacement in the vertical direction.

[0059] To further secure the displacement monitoring element 20 and avoid displacement deviation, the LVDT displacement gauge needs to be fixedly connected to the right container body using hot melt adhesive. This prevents positional deviation of the LVDT displacement gauge from causing reading errors. The sensing element is preferably an iron sheet, set parallel to the side wall of the right container body 2. The iron sheet has an area of ​​approximately 4 cm² and a thickness of approximately 2 mm, and is used to monitor the soil displacement within the filter press shear chamber. The sensing element increases the contact area with the soil, making the displacement monitoring more accurately reflect the actual soil displacement. Furthermore, the parallel placement of the sensing element to the right side wall of the right container body 2 helps maintain the measurement direction of the LVDT displacement gauge consistent with the soil displacement direction, further improving monitoring accuracy.

[0060] In this embodiment, the first pressure monitoring element 21 is preferably a pressure sensor, which is fixed to the inner wall of the right container body 2 by hot melt adhesive. Three sensors are arranged at equal intervals from top to bottom along the height direction of the right container body 22 to monitor the pressure of the soil inside the right container body 22 on the filter shear container wall. The three pressure sensors can monitor the pressure of the soil inside the right container body 22 on the filter shear container wall at different height positions. The pressure of the soil on the container wall may vary in the vertical direction. Multiple pressure sensors can provide a comprehensive understanding of the distribution of soil pressure, providing more detailed data for analyzing the mechanical behavior of the soil during the filter shear process.

[0061] The pressurized grouting and constant pressure device 3 includes a slurry storage container 30 and a pressure conveyor 31. The slurry storage container 30 is connected to the filter press shearing chamber; the pressure conveyor 31 is connected to the slurry storage container 30 and is used to transport air and slurry in the slurry storage container 30 to the filter press shearing chamber. The slurry storage container 30 is equipped with a second pressure monitoring element and a regulating valve for adjusting the pressure inside the pressurized grouting and constant pressure device 33. The regulating valve is located on the connection channel between the slurry storage container (30) and the pressure conveyor. The second pressure monitoring element is used to monitor the pressure value inside the pressurized grouting and constant pressure device 3. Specifically, the pressure conveyor 31, the slurry storage container 30, and the filter press shearing chamber are connected sequentially. In this embodiment, the pressure conveyor 31 can be an air compressor. When no slurry is placed in the slurry storage container 30, starting the pressure conveyor 31 can input air into the filter press shearing chamber, increasing the pressure inside the filter press shearing chamber. When slurry is placed in the slurry storage container 30, the pressure conveyor 31 can be started to inject slurry into the filter press shear chamber and maintain a certain pressure.

[0062] A pressurization and temperature control device 4 is installed on the exterior of the filter press shear container near the left container body 1. The pressurization and temperature control device 4 connects the inlet 101 and outlet 102 of the S-shaped water pipe 10 inside the left container body 1. Specifically, the pressurization and temperature control device 4 includes a water storage container 40 and a connecting water pipe 41. The water storage container 40 is equipped with a heating structure to heat the water flow in the circulating water path. The connecting water pipe 41 passes through the water storage container 40, and the heating structure is located on the outer wall of the connecting water pipe 41 inside the water storage container 40. Both ends of the connecting water pipe 41 are connected to the inlet 101 and outlet 102 of the S-shaped water pipe 10, respectively, forming a closed circulating water path. The pressurization and temperature control device 4 adjusts the water temperature inside the S-shaped water pipe 10 to determine the effect of different water temperatures on the performance of the pile body inside the left container body 1.

[0063] In this embodiment, a circulating water pump 42 is installed on the connecting water pipe 41 inside the water storage container 40, which accelerates water circulation. The water storage container 40 contains recyclable water, which reduces energy consumption and improves the stability of the equipment water temperature and the water flow rate. In this embodiment, the capacity of the water storage container 40 is 40L. In this embodiment, heating structures are installed on the connecting water pipes 41 on both sides of the circulating water pump 42 inside the water storage container 40. In this application, the heating structure is preferably a 25W carbon fiber heating wire 43, which has high conversion efficiency and low load on the pressurization and temperature control device 4 during long-term use, meeting the experimental requirements. The shear loading device 5 is installed outside the filter press shear container and is used to apply tangential and normal forces to the right container body 2 and monitor the displacement of the right container body 2 along the directions of the tangential and normal forces. The shear loading device 5 includes a fixed frame 50, a tangential force loading structure 51 mounted on the fixed frame 50, and a normal force loading structure 52 mounted on the fixed frame 50. The tangential force loading structure 51 abuts against the side wall of the right container body 2, and the side wall is also provided with a tangential force sensor and a shear displacement sensor. The normal force loading structure 52 abuts against the bottom wall of the right container body 2 away from the left container body 1, and the bottom wall is also provided with a normal force sensor and a normal displacement sensor. The top of the left container body 1 is connected to the top of the fixed frame 50 of the shear loading device 5 through a connecting frame. The fixed frame 50 is also provided with a plurality of fixing posts 54, which abut against the side wall of the left container body 1 for fixing the left container body 1.

[0064] By installing tangential force sensors, shear displacement sensors, normal force sensors, and normal displacement sensors, the magnitudes of tangential and normal forces, as well as the displacement of the right container body 2 in the corresponding directions, can be monitored in real time. This provides accurate data for studying the mechanical behavior of the pile-grout-soil interface under shear and normal forces. Simultaneously, by monitoring changes in displacement and stress, the deformation, strength characteristics, and failure modes of the pile-grout-soil interface at different loading stages can be understood, providing a basis for assessing the stability and reliability of the interface.

[0065] In this embodiment, both the tangential force loading structure 51 and the normal force loading structure 52 are jacks, one horizontally positioned and the other vertically positioned. The jacks provide stable and controllable loading forces. By adjusting the pressure of the jacks, the magnitudes of the tangential and normal forces applied to the right container body 2 can be precisely controlled to meet the needs of different experimental conditions. Furthermore, jacks are common loading devices with relatively simple operation. Experimenters can easily adjust the pressure of the jacks to control different loading levels, improving the operability and efficiency of the experiment.

[0066] The thermosetting and shear property testing system of this invention, through the synergistic action of the pressure filter shear container, the pressurized grouting and constant pressure device 3, the pressurization and temperature control device 4, and the shear loading device 5, can comprehensively simulate the thermosetting and shear properties of the pile-grout-soil contact interface in actual engineering, providing a reliable experimental means for studying the performance of non-displacement piles in practical applications. Furthermore, by studying the thermosetting and shear properties of the pile-grout-soil contact interface, the design and construction process of pile foundations can be optimized, improving the safety and durability of buildings.

[0067] Meanwhile, the first temperature sensor 11 inside the left container body 1 can accurately monitor the temperature changes of the concrete grout, which helps to study the influence of temperature on pile performance and provides data support for optimizing the design and construction of energy piles. The displacement monitoring element 20 and the first pressure monitoring element 21 on the right container body 2 can monitor the displacement of the soil and the pressure of the soil on the container wall, respectively, providing key data for analyzing the deformation and stress characteristics of the soil around the pile during thermal consolidation and shearing processes. The pore pressure sensor 23 inside the right container body 2 can monitor the pore pressure of the soil, which is of great significance for studying the changes in pore water pressure of the soil during thermal consolidation and shearing processes. The second pressure monitoring element in the pressurized grouting and constant pressure device 3 can monitor the internal pressure value of the system, which facilitates precise control of the grouting pressure and ensures the accuracy and repeatability of experimental conditions. Moreover, the regulating valve in the pressurized grouting and constant pressure device 3 can adjust the internal pressure of the system, which can simulate the performance changes of the pile-grout-soil contact interface under different grouting pressure conditions, providing a basis for optimizing the design and construction of energy piles. By adjusting the water temperature in the water pipe through the pressurization and temperature control device 4, the performance changes of the pile under different temperature environments can be simulated, and the thermo-solid characteristics of the energy pile under different working temperatures can be studied.

[0068] As can be seen, this invention can collect data on various parameters, such as temperature, displacement, pressure, and pore water pressure, through various monitoring elements, providing rich data support for in-depth research on the characteristics of the "pile-grout-soil" contact interface.

[0069] Furthermore, the coordinated operation of all systems reduces human error during the experiment, improving efficiency and accuracy. The sealed connections and precise monitoring components ensure the stability and reliability of experimental conditions, guaranteeing accurate results. This technology can provide a scientific basis for the design, construction, and performance evaluation of non-displacement piles, contributing to improved application levels and market competitiveness of green energy utilization technologies such as energy piles.

[0070] In this embodiment, the left container body 1 and the right container body 2 are detachably fixedly connected. The first, second, and third connecting strips at the joint between the left and right container bodies 1 and 2 are preferably rubber sealing strips. The two ends of the third connecting strip are connected to the first and second connecting strips respectively using bolts, achieving a sealed and fixed connection between the left and right container bodies 1 and 2. Specifically, the rubber sealing strips wrap around the joint between the left and right container bodies 2 at least once. Hot melt adhesive can be used to bond the connecting strips to the container bodies, and adjacent rubber sealing strips can be fixed together with bolts. The rubber sealing strips wrapping around the joint between the left and right container bodies 2 at least once create a good sealing effect, preventing liquid or gas leakage during the experiment, thereby ensuring the accuracy and stability of the experimental conditions. In this embodiment, three through holes are opened at the top of the pressure filtration shear chamber formed by the joint of the rubber sealing strips. The first through hole 61 is used to house the input pipe of the pressure conveyor 31; the second through hole 62 is used for venting during grouting or for pressure filtration during the pressure conveyor 31, and the second through hole 62 can be sealed with hot melt adhesive; the third through hole 63 is used to house a pressure gauge, and after the pressure gauge is installed, the through hole 63 can be sealed with hot melt adhesive. After the pressurized grouting and constant pressure devices are removed, the first through hole 61 and the second through hole 62 must be sealed.

[0071] In this embodiment, both the left container body 1 and the right container body 2 are made of transparent acrylic sheets, so that the outside world can directly observe whether the soil inside the filter shear chamber is compacted or the progress of the filter process through the acrylic sheets.

[0072] The thermosetting and shear property testing system also includes a PIV monitoring device, which is located outside the filter press shear vessel. The PIV monitoring device includes a tripod and a camera mounted on the tripod, used to capture and record dynamic changes inside the filter press shear vessel.

[0073] During use, adjust the tripod to the same height as the middle of the filter press shearing container, then fix the tripod to the ground to prevent movement. This ensures the tripod remains stable during filming and will not shake due to slight external forces, thus guaranteeing stable camera recording of the contents of the container. Avoid touching the tripod during filming, as even slight contact can cause camera shake, affecting the accuracy and clarity of the footage.

[0074] The camera selected has a standby time of over 10 hours and a memory card capacity greater than 64GB to meet the needs of long-term shooting, eliminating the need for frequent interruptions to deal with power or storage shortages, and ensuring complete recording of the entire process from start to finish when the specimen is completely sheared. After powering on, the camera is fixed on a tripod and remotely controlled via Bluetooth, which is convenient to operate and reduces the impact of human proximity on shooting stability. Ten photos are taken after each increase in shear strength and when the stress stabilizes. These photos can be used for later PIV software analysis, which can record in detail the changes in the pile-grout-soil interface under different shear strengths. By comparing and analyzing multiple sets of photos, the failure development trend of the interface during the shearing process can be observed more accurately. Continuous shooting until the specimen is completely sheared and the final failure mode is recorded, providing intuitive and comprehensive image data for studying the thermosetting and shear characteristics of the pile-grout-soil interface, which helps to deeply analyze the failure mechanism and performance change law of the interface.

[0075] Preferably, the thermosetting and shear property testing system of the present invention also includes a data collection and processing module, which includes a data collector and a computer. The data collector is connected to the filter press shear container, the pressurized grouting and constant pressure device 3, the pressurization and temperature control device 4, the shear loading device 5, the slurry collection and detection device 7 and the PIV monitoring device through multiple 5m long data connection lines. The data collector is also connected to the computer to uniformly transmit the collected data information to the computer for unified data processing.

[0076] Using the unique software of each device, individual on / off operations and data collection and processing can be performed. The software used includes Origin and PIVview2CDemo. After installing Origin on the computer, preset values ​​are set for the pressure, constant pressure, heating rate, and constant temperature. This allows the integration of shear values ​​with soil pore pressure and displacement values ​​to form a 3D graph. After installing PIVview2CDemo on the computer, photos from the camera are imported into the same folder. By comparing every two images and continuously playing the comparison images, a dynamic graph of the pile-grout-soil interface from its intact state to its failed state can be generated. Finally, the dynamic graph is edited using a computer to create a video of the entire process of the failure interface formation.

[0077] Secondly, the present invention provides a method for testing the thermo-firm and shear properties of the contact interface of a non-displacement pile, based on the above-mentioned thermo-firm and shear property testing system, comprising the following steps:

[0078] Step S01: Fabricate the left container body 1, and install the S-shaped water pipe 10 and the first sensor on the left container body 1;

[0079] In this embodiment, two identical, sufficiently strong, unsealed, cubic transparent acrylic boxes serve as the outer shells of the left container body 1 and the right container body 2, respectively, acting as shear boxes for casting models and for shearing tests. The transparent acrylic box serving as the left container body 1 has two pre-drilled circular holes on its bottom wall away from the right container body 2, each with a diameter equal to that of the S-shaped water pipe 10. This allows the inlet 101 and outlet 102 of the PC plastic S-shaped water pipe 10 to pass through these holes. The S-shaped water pipe 10 is then fixed inside the left container body 1 using an iron frame and bolts. The inlet 101 and outlet 102 of the S-shaped water pipe 10 are then sealed to the circular holes to prevent displacement. Next, the first temperature sensor 11 is fixedly installed at the interface of the left container body 1 using a support rod, and is connected to the data collection and processing module via a data connection cable.

[0080] Step S02: After wrapping the first connecting strip around the interface of the left container body 1 at least once, fix it and seal the connection.

[0081] The first connecting strip is a detachable rubber sealing strip that can surround the interface of the acrylic box at least once. The rubber sealing strip is the same thickness as the acrylic box and is placed between two oppositely arranged acrylic boxes to facilitate the pouring of concrete and the placement of soil, as well as to facilitate the formation of a shear pile-grout-soil interface that protrudes from the acrylic plate.

[0082] Step S03: With the interface of the left container body 1 facing upward, fill the left container body 1 with concrete. The concrete must fill the left container body 1 completely, that is, be level with its interface surface, and cure it at 25°C for 28 days.

[0083] In this embodiment, concrete with a water-cement ratio of 0.3 and a strength of C80 is poured into the outer shell of the left container body 1 using an auxiliary container, and the concrete is vibrated to reduce air bubbles. After 2 to 4 hours of pouring, the concrete surface is continuously, evenly, and gently sprayed with water using a sprinkler pool to ensure that water covers the concrete surface and avoids water accumulation. The above operation is continued, and the concrete is cured at 25°C for 28 days.

[0084] Step S04: Fabricate the right container body 2, install the displacement monitoring element 20, the first pressure monitoring element 21, and the pore pressure sensor 23 on the right container body 2, fix the second connecting strap around the interface of the right container body 2 and seal the connection; with the interface of the right container body 2 facing upwards, fill the right container body 2 with soil, and compact the soil with a heavy hammer during the filling process. The soil inside the right container body 2 must be flush with the interface surface of the right container body; at the same time, open the valve at the drain hole 22 during the compaction process to receive the seepage water in the soil.

[0085] Three small circular holes are made on the side wall of the transparent acrylic box that serves as the main body of the right container 2. These holes are for displacement monitoring elements 20, and LVDT displacement gauges are placed inside them and fixed with hot melt adhesive. The bottom of each LVDT displacement gauge is located inside the main body of the right container 2. Correspondingly, a 4cm², 2mm thick iron sheet is welded to the bottom of each LVDT displacement gauge. Three first pressure monitoring elements 21, i.e., pressure sensors, are glued to the side wall of the right container 2 on the same side as the displacement monitoring elements 20. The three pressure sensors are evenly spaced along their height. Simultaneously, at the interface of the right container 2, multiple orifice pressure sensors 23 are fixed to the second support frame 24 via a second support frame 24. The orifice pressure sensors are evenly spaced and fixed to the second support frame 24.

[0086] Twenty-five circular holes, each 2mm in diameter and arranged in a 5x5 matrix, are made at the lower right corner of the right container body 2. The spacing between adjacent holes is 2cm. These holes serve as drainage holes 22. A steel funnel is welded to the outside of the drainage holes 22. A valve is installed at the bottom of the steel funnel to control the outflow of water stored in the funnel. A rubber sealing strip is wrapped around the interface of the right container body 2 at least once and then fixed with hot melt adhesive. The LVDT displacement gauge, the first pressure monitoring element 21, and the pore pressure sensor 23 are connected to the data collection and processing module via a data connection cable. Then, with the opening of the right container body 2 facing upwards, soil is filled into the right container body 2. During the filling process, a heavy hammer is used to compact the soil. Simultaneously, during compaction, the valve at the bottom of the steel funnel is opened to collect seepage from the soil.

[0087] During soil compaction, the internal moisture seeping from the small holes is collected, and its internal chemical composition is preliminarily analyzed using a water quality analyzer. This allows for a comparison of whether changes in the chemical properties of the soil surrounding the grout-soil interface, due to the grout's penetration into the soil during grouting, improve the bearing capacity of the grout-soil interface.

[0088] Step S05: Align the left container body 1 after curing with the right container body 2 after backfilling, and connect the first and second connecting strips with the third connecting strip and seal the connection to achieve the docking connection between the left container body 1 and the right container body 2, forming a pressure filter shearing chamber at the connection. An input hole for the input pipe of the pressure grouting and constant pressure device 3 is provided at the top of the pressure filter shearing chamber and connected to the input pipe of the pressure grouting and constant pressure device 3. An exhaust hole is provided for venting or for use when the input pipe of the pressure grouting and constant pressure device 3 is used for pressure filtration. A pressure gauge is provided at the top of the pressure filter shearing chamber.

[0089] Step S06: Before grouting, turn on the PIV monitoring device, point the camera of the PIV monitoring device at the entire filter press shear container, and fix the position of the filter press shear container and the camera; grouting is carried out, the vent is opened, and the grout containing pigment in the grout storage container 30 of the pressurized grouting and constant pressure device 3 is injected into the filter press shear chamber through the pressure conveyor 31. Record the displacement deformation of the displacement detection element, the change of pore pressure of the pore pressure sensor 23, and the change of soil pressure before and after grouting of the pressure sensor during the grouting process. At the same time, collect the soil seepage water under the action of grouting through the drainage hole 22 at the right container body 2.

[0090] In this step, the water seepage from the soil under grouting can be collected and analyzed in a water quality analyzer. The chemical composition can be compared with that in the natural seepage from the soil to observe whether the grout has a reinforcing effect on the surrounding soil. During the grouting process, the PIV monitoring device takes pictures to analyze the penetration effect of the grout on the soil.

[0091] Step S07: After the filter press shear chamber is filled with grout, the vent hole is sealed to seal the filter press shear chamber. Constant pressure is applied to the grouting chamber through the pressure conveyor 31, and the pressure gauge is used to monitor the pressure in real time to cure the newly injected grout under constant pressure. At the same time, the seepage water in the soil is collected through the drain hole 22 at the right container body 2 and compared with the chemical substances contained in the seepage water of the soil before grouting.

[0092] In this embodiment, the pressure conveyor 31 applies a constant pressure of 5 MPa to the grouting chamber.

[0093] While waiting for the grout to solidify, the seepage water in the soil is continuously collected and compared with the chemical substances contained in the seepage water of the previous natural soil. The analysis is conducted to determine whether the grout has a chemical reaction with the surrounding soil. If a chemical reaction occurs, the changes in substances are analyzed, and whether the new substances have an improving effect on the bearing capacity of the soil around the grout-soil interface.

[0094] Step S08: After the grout has completely solidified, a pile-grout-soil model test block is obtained;

[0095] Prepare five identical pile-grout-soil model test blocks according to steps S01-S07;

[0096] Remove the connecting strip and connect the inlet 101 and outlet 102 of the S-shaped water pipe 10 of the pile-grout-soil model test block to the pressurization and temperature control device 4. The pressurization and temperature control device 4 pushes, cools, and heats the circulating water in the water pipe to achieve temperature control. Water at 10℃, 20℃, 30℃, 40℃, and 50℃ is introduced into the five pile-grout-soil model test blocks respectively, and the water introduction time is 2 hours for each time. The effect of the water on the pile body temperature is analyzed by the first temperature sensor 1111 in the left container body 1.

[0097] Step S09: Rotate the pile-grout-soil model test block so that the right container is at the bottom and vertically upward. Place the pile-grout-soil model test block inside the shear loading device 5, so that the tangential force loading structure 51 abuts against the side wall of the right container body 2, and the normal force loading structure 52 abuts against the bottom of the right container body 2. The tangential force loading structure 51 and the normal force loading structure 52 provide tangential and normal forces. The PIV monitoring device records the failure process of the pile-grout-soil interface and the intuitive displacement of the pile or soil. The pore pressure sensor 23 detects the pore pressure inside the soil. The pressure sensor measures the change in pressure on the soil under the shear dilatation of the side soil when the pile-grout-soil is subjected to tangential force. The displacement monitoring element 20 measures the displacement of the soil. At the same time, collect the seepage water in the soil and observe the seepage of the soil under the influence of tangential force.

[0098] Record the maximum shear strength of the pile-grout-soil model specimens after failure at five different temperatures and perform final analysis.

[0099] S10: After the pile-grout-soil model test block is destroyed, the soil part that has been contaminated with pigment is excavated, and the remaining uncontaminated part is retained to observe the penetration effect of the grout on the soil.

[0100] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A testing system for the thermo-firm and shear properties of the contact interface of a non-displacement pile, characterized in that, It comprises a filter pressing shear container, a pressurized grouting and constant pressure device (3), a pressurizing and temperature control device (4), and a shear loading device (5), wherein: The filter pressing shear container comprises a left container body (1) for containing concrete and a right container body (2) for containing soil, the left container body (1) and the right container body (2) are connected in a left-right manner and sealed by a connecting belt, forming a filter pressing shear chamber, wherein an S-shaped water pipe (10) is arranged in the left container body (1), and the water inlet (101) and the water outlet (102) of the S-shaped water pipe (10) are arranged on the top wall of the left container body (1); The pressurized grouting and constant pressure device (3) comprises a slurry storage container (30) and a pressure conveyor (31), the slurry storage container (30) is in communication with the filter pressing shear chamber, and the pressure conveyor (31) is in communication with the slurry storage container (30) and used for conveying air and slurry in the slurry storage container (30) to the filter pressing shear chamber; The pressurizing and temperature control device (4) is arranged outside the filter pressing shear container near the left container body (1), the pressurizing and temperature control device (4) is in communication with the water inlet (101) and the water outlet (102) of the S-shaped water pipe (10) in the left container body (1), and the water inlet (101) and the water outlet (102) of the S-shaped water pipe (10) are arranged on the top wall of the left container body; The shear loading device (5) is arranged outside the filter pressing shear container and used for loading the right container body (2) with tangential force and normal force and monitoring the displacement of the right container body (2) in the tangential force and normal force directions; A plurality of first temperature sensors (11) are fixed on the abutting interface of the left container body (1) by a first support frame (12), the plurality of first temperature sensors (11) are fixed and installed on the first support frame (12) at equal intervals, a plurality of pore pressure sensors (23) are fixed on the abutting interface of the right container body (2) by a second support frame (24), the plurality of pore pressure sensors (23) are fixed and installed on the second support frame (24) at equal intervals, a displacement monitoring element (20), a first pressure monitoring element (21) and a drainage hole (22) are arranged on the bottom wall of the right container body (2) away from the left container body (1), the displacement monitoring element (20) is used for monitoring the displacement of the soil in the filter pressing shear chamber, the first pressure monitoring element (21) is used for monitoring the pressure of the soil in the right container body (2) on the container wall of the right container body (2), and the drainage hole (22) is used for collecting and detecting slurry. The pressurizing and temperature control device (4) comprises a water storage container (40) and a connecting water pipe (41), the water storage container (40) is provided with a heating structure, the connecting water pipe (41) penetrates through the water storage container (40), the heating structure is arranged on the outer wall of the connecting water pipe (41) in the water storage container (40), a circulating water pump (42) is arranged on the connecting water pipe (41) in the water storage container (40), and the two ends of the connecting water pipe (41) are communicated with the water inlet (101) and the water outlet (102) of the S-shaped water pipe (10) respectively to form a closed circulating water path. The shear loading device (5) comprises a fixing frame (50), a tangential force loading structure (51) and a normal force loading structure (52), the tangential force loading structure (51) and the normal force loading structure (52) are both mounted on the fixing frame (50), the tangential force loading structure (51) abuts against a side wall of the right container body (2), and a tangential force sensor and a shear displacement sensor are further arranged on the side wall, the normal force loading structure (52) abuts against a bottom wall of the right container body (2) away from the left container body (1), and a normal force sensor and a normal displacement sensor are further arranged on the bottom wall, the top of the fixing frame (50) is connected to the top of the left container body (1) through a connecting frame, and a plurality of fixing columns (54) are further arranged on the fixing frame (50) and abut against the side walls of the left container body (1).

2. The system for testing thermal and shear properties of the contact interface of a non-displacement pile according to claim 1, wherein, The slurry storage container (30) is provided with a second pressure monitoring element and an adjusting valve, the adjusting valve is arranged on a connecting channel of the slurry storage container (30) and the pressure conveyor, and the adjusting valve is used for adjusting the pressure in the pressurized grouting and constant pressure device (3).

3. The system for testing thermal and shear properties of a contact interface of a non-displacement pile according to claim 1, wherein, A plurality of through holes are arranged on the top of the filter-pressing shear chamber, at least including a first through hole (61), a second through hole (62) and a third through hole (63), the first through hole (61) is used for placing an input pipe of the pressure conveyor (31), the second through hole (62) is used for exhausting air during grouting or is used during filter pressing by the pressure conveyor (31), and the third through hole (63) is used for placing a pressure gauge.

4. The system for testing thermal and shear properties of a contact interface of a non-displacement pile according to claim 1, wherein, The system further comprises a PIV monitoring device, the PIV monitoring device is fixed outside the filter-pressing shear container, and a camera of the PIV monitoring device is aimed at the whole filter-pressing shear container and is used for observing the internal changes of the filter-pressing shear container.

5. The system for testing thermal and shear properties of a contact interface of a non-displacement pile according to claim 1, wherein, The displacement monitoring element (20) comprises an LVDT displacement meter and an inductive sheet, the inductive sheet is parallel to the side wall of the right container body (2) and is arranged inside the right container body (2), and the inductive sheet is connected with the bottom of the LVDT displacement meter.

6. A method for testing thermal and shear properties of a contact interface of a non-displacement pile, characterized in that, The thermal solidification and shear property testing system according to any one of claims 1-5 comprises the following steps: S01, manufacturing a left container body (1), installing an S-shaped water pipe (10) of the left container body (1) and a first temperature sensor (11); S02, winding a first connecting belt around the butt joint of the left container body (1) for one turn, fixing the first connecting belt and sealing the connection; Step S03, the left container body (1) is filled with concrete, and the concrete is filled to the level of the left container body (1) and is cured for 28 days at 25 DEG C; Step S04, the right container body (2) is made, the displacement monitoring element (20), the first pressure monitoring element (21), the pore pressure sensor (23) are installed, the second connecting belt is wound around the right container body (2) and is fixed, the connection is sealed, the right container body (2) is filled with soil, and the soil in the right container body (2) is tamped by using a heavy hammer during filling, so that the soil in the right container body (2) is leveled with the right container body (2), and the valve at the drainage hole (22) is opened during tamping to receive the percolation water in the soil; Step S05, the left container body (1) and the right container body (2) are connected, the third connecting belt is connected to the first connecting belt and the second connecting belt by bolts, the left container body (1) and the right container body (2) are connected, and a pressure filtration shear chamber is formed at the connection, an input hole for the input pipe of the pressurized grouting and constant pressure device (3) is arranged at the top of the pressure filtration shear chamber, the input pipe of the pressurized grouting and constant pressure device (3) is communicated, an exhaust hole for exhaust or pressurized grouting and constant pressure device (3) input pipe is arranged, and a pressure gauge is arranged at the top of the pressure filtration shear chamber; Step S06, before grouting, the PIV monitoring device is started, the camera of the PIV monitoring device is aimed at the pressure filtration shear container, and the position of the pressure filtration shear container and the camera is fixed; grouting is carried out, the exhaust hole is opened, the grouting in the storage container (30) of the pressurized grouting and constant pressure device (3) is injected into the pressure filtration shear chamber through the pressure conveyor (31), the displacement deformation of the displacement detection element, the change of the pore pressure of the pore pressure sensor (23) and the change value of the soil pressure before and after grouting of the first pressure monitoring element (21) are recorded, and the percolation water of the soil under the action of grouting is collected through the drainage hole (22) of the right container body (2); Step S07, after the pressure filtration shear chamber is filled with grout, the exhaust hole is blocked, the pressure filtration shear chamber is sealed, a constant pressure is applied to the grouting chamber through the pressure conveyor (31), the pressure is monitored in real time, the newly injected grout is maintained at a constant pressure, and the percolation water in the soil is collected through the drainage hole (22) of the right container body (2), and the chemical substances contained in the percolation water of the soil before grouting are compared; Step S08, the pile-grout-soil model test block is obtained after the grout is completely solidified; Five same pile-grout-soil model test blocks are made according to steps S01-S07; The connecting belt is removed, the water inlet (101) and the water outlet (102) of the S-shaped water pipe (10) of each pile-grout-soil model test block are connected with the pressurizing and temperature control device (4), and the pressurizing and temperature control device (4) is connected with the water inlet (101) and the water outlet (102) of the S-shaped water pipe (10) of each pile-grout-soil model test block. Step S09, rotate the pile-slurry-soil model test block so that the right container is at the bottom and vertically upward, and place the pile-slurry-soil model test block in the shearing loading device (5), so that the tangential force loading structure (51) abuts against the side wall of the right container body (2), and the normal force loading structure (52) abuts against the bottom of the right container body (2), the tangential force and the normal force are provided by the tangential force loading structure (51) and the normal force loading structure (52), the PIV monitoring device records the destruction process of the pile-slurry-soil interface and the direct displacement of the pile body or the soil body, the pore pressure sensor (23) detects the internal pore pressure of the soil body, the first pressure monitoring element (21) measures the change of the pressure of the soil body under the lateral soil dilatancy when the pile-slurry-soil is subjected to the tangential force; the displacement monitoring element (20) measures the displacement of the soil body; at the same time, collect the seepage water in the soil body and observe the seepage condition of the soil body under the influence of the tangential force; Record the maximum shear value of the pile-slurry-soil model test block after being destroyed at five different temperatures and perform final analysis; S10: After the pile-slurry-soil model test block is destroyed, dig out the part of the soil body invaded by the pigment, and reserve the remaining part not invaded, to observe the penetration effect of the slurry on the soil body.

7. The method for testing thermal and shear properties of the contact interface of a non-displacement pile according to claim 6, wherein, In the step S08, the five pile-slurry-soil model test blocks are respectively supplied with water at 10℃, 20℃, 30℃, 40℃ and 50℃, and the water supply time is 2 hours.

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