Soil-structure interface unsaturated temperature control direct shear specimen box

Abstract

The application provides a soil-structure interface non-saturated temperature control direct shear sample box, which comprises the following: the inside of the upper shear box is surrounded by a soil sample cavity wall to form a non-saturated soil sample cavity, the non-saturated soil sample cavity is used for containing a non-saturated soil sample; two opposite side walls in the first direction of the outer box body are respectively provided with T-shaped grooves; the soil sample cavity wall is respectively embedded with a water-permeable stone and a pottery clay plate, and the water-permeable stone and the pottery clay plate are directly connected to the outside of the outer box body through pipelines; the lower shear box is provided with a structure material installation cavity used for installing a structure material sample; the upper shear box and the lower shear box are in a superposed state, the box body of the lower shear box is provided with a temperature control water bath pipeline, and the temperature control water bath pipeline is isolatedly arranged with the structure material installation cavity, and the application solves the problems of long saturation regulation path, large sample disturbance, temperature control structure dependent on whole machine modification and insufficient shear box and interface sample adaptability in the soil-structure interface shear test in the prior art.

Description

Technical Field

[0001] This utility model relates to the technical field of structural interface shear testing equipment, specifically to a soil-structure interface unsaturated temperature-controlled direct shear test box. Background Technology

[0002] Soil-structure interfaces are widely found in engineering applications such as pile-soil interfaces, retaining wall-soil interfaces, lining-soil interfaces, geosynthetic-soil interfaces, and foundation-soil interfaces. The shear strength of the interface is influenced by factors including soil moisture content, saturation, matrix suction, temperature, surface properties of the structural materials, and normal pressure. For unsaturated soil-structure interfaces, accurately controlling soil saturation and stably regulating the interface temperature are crucial for obtaining reliable interface mechanical parameters.

[0003] Existing direct shear devices for unsaturated soil or soil-structure interfaces typically incorporate a pressure chamber, humidity control module, infiltration water supply module, and freeze-thaw or water bath temperature control module from a holistic perspective. For example, existing unsaturated soil-structure interface shear apparatuses that control relative humidity often control the test environment through a closed pressure chamber and humidity control module; existing multi-functional shear box direct shear devices can improve shear tests based on freeze-thaw or temperature environments; and existing dry-wet cycle infiltration direct shear devices can perform infiltration and shearing processes on the same sample. While each of these devices has its applicable scenarios, they still have the following shortcomings when used as replacement sample box components: First, saturation control often relies on the end face, ambient humidity, or overall piping, resulting in a long control path; second, soil sample transfer or changes in the external environment may cause sample disturbance; third, the temperature control structure often relies on the entire machine or external cavities, making it difficult to directly modify the sample box without altering the main structure of the direct shear loading equipment; and fourth, some devices are not designed for sample box structures where the upper unsaturated soil sample and the lower structural material sample directly form an interface shear surface. Utility Model Content

[0004] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a soil-structure interface unsaturated temperature-controlled direct shear test box, which solves the problems of long saturation control path, large sample disturbance, reliance on whole machine modification for temperature control structure, and insufficient compatibility between shear box and interface sample in the existing soil-structure interface shear test.

[0005] To achieve the above technical objectives, the present invention provides a soil-structure interface unsaturated temperature-controlled direct shear sample box, including an upper shear box and a lower shear box. The upper shear box includes an outer box body and a soil sample cavity wall disposed within the outer box body. The soil sample cavity wall encloses and forms an unsaturated soil sample cavity, which is used to contain unsaturated soil samples.

[0006] With the shearing direction as the first direction and the direction perpendicular to the shearing direction in the horizontal plane as the second direction, the outer box body is provided with T-shaped grooves on the two opposite side walls along the first direction. The T-shaped grooves are used to cooperate with the shearing drive component of the external direct shear loading device.

[0007] The walls of the soil sample chamber are inlaid with permeable stones and clay plates respectively. Both the permeable stones and the clay plates have contact surfaces exposed to the unsaturated soil sample chamber for direct contact with the sides of the unsaturated soil sample. Both the permeable stones and the clay plates are directly connected to the outside of the outer box through pipes.

[0008] The lower shear box is provided with a structural material mounting cavity for mounting structural material samples. When the upper shear box and the lower shear box are stacked, the lower surface of the unsaturated soil sample and the upper surface of the structural material sample form a soil-structure interface shear surface. The lower shear box is provided with a temperature-controlled water bath pipeline, which is isolated from the structural material mounting cavity.

[0009] Compared with the prior art, the beneficial effects of this utility model include:

[0010] This application integrates the functions of unsaturated soil saturation control and interface temperature control into a replaceable direct shear sample box body. It can be directly adapted without modifying the main structure of existing direct shear loading equipment, significantly reducing test upgrade costs. By embedding terracotta plates and permeable stones on the sides of the upper shear box to directly form the lateral boundary of the soil sample cavity, moisture control and gas-liquid exchange are achieved directly from the side of the soil sample. Compared with traditional end-face seepage and environmental humidity control methods, this significantly shortens the saturation control path. Furthermore, the soil sample can be loaded into the box once to complete the moisture balance and shear test, completely avoiding structural disturbance during sample transfer. Combined with the terracotta plates and permeable stones on both sides... The arrangement of stones on the two opposite outer walls of the soil sample chamber along the second direction effectively improves the uniformity of soil saturation field control. The lower shear box adopts a built-in temperature-controlled water bath pipeline that is completely isolated from the structural sample installation cavity. It can precisely control the soil-structure interface temperature through the structural material side, and the temperature control medium will not contact the sample or interfere with the original water content of the soil sample. The shear drive connection structure and water-air control structure are arranged in different directions on different side walls of the box, with clear functional zoning and no interference between them. All structures are contained within the outer contour of the box, with a compact structure and reliable sealing performance. It can be widely adapted to the interfacial shear mechanical property testing of various engineering structural materials and unsaturated soils.

[0011] According to some embodiments of this utility model, the lower shear box further includes:

[0012] The structural material support platform and the limiting wall surrounding the structural material support platform are arranged around the outside of the structural material mounting cavity. The structural material support platform is located below the structural material mounting cavity, and the temperature-controlled water bath pipeline is arranged around the outside of the limiting wall.

[0013] According to some embodiments of the present invention, the upper surface of the structural material support platform is flush with or 0.1 mm to 1 mm higher than the upper surface of the lower shear box, so that the upper surface of the structural material sample can form the soil-structure interface shear surface with the lower surface of the unsaturated soil sample.

[0014] According to some embodiments of the present invention, a temperature control medium inlet and a temperature control medium outlet for connecting an external circulating temperature control source are provided on the outer surface of the lower shear box. The temperature control medium inlet is connected to the liquid inlet end of the temperature control water bath pipeline, and the temperature control medium outlet is connected to the liquid outlet end of the temperature control water bath pipeline.

[0015] According to some embodiments of the present invention, a temperature sensor is provided inside the lower shear box, and the temperature sensor is used to detect the temperature of the lower shear box.

[0016] According to some embodiments of the present invention, the T-shaped groove includes a wide groove section near the unsaturated soil sample cavity and a narrow groove section that communicates with the wide groove section and extends to the outer side of the upper shear box.

[0017] According to some embodiments of the present invention, the upper shear box is further provided with a moisture control chamber and a gas-liquid exchange chamber. The terracotta plate is connected to the moisture control chamber through a pipe, and the permeable stone is connected to the gas-liquid exchange chamber through a pipe. Both the moisture control chamber and the gas-liquid exchange chamber are located on the outer surface of the upper shear box.

[0018] According to some embodiments of this utility model, the temperature-controlled water bath pipeline is located inside the bottom wall or side wall of the lower shear box, and is at least partially arranged around the structural material mounting cavity; the temperature-controlled water bath pipeline is a ring pipeline, a serpentine pipeline, a U-shaped pipeline, or a multi-segment parallel pipeline.

[0019] According to some embodiments of the present invention, the upper shear box or the lower shear box is provided with a positioning surface, a connecting hole, a guide groove or a limiting step that cooperates with an external direct shear loading device.

[0020] According to some embodiments of the present invention, the outer side of the upper shear box is provided with a detachable pressure cover and a sealing ring. The detachable pressure cover is used to press the clay plate or the permeable stone, and the sealing ring is pressed between the detachable pressure cover and the upper shear box.

[0021] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] The above and / or additional aspects and advantages of this invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein the abstract drawings are to be completely consistent with one of the drawings in the specification:

[0023] Figure 1 A top view of the upper shear box provided in one embodiment of the present invention;

[0024] Figure 2 This is a top view of the lower shear box provided in one embodiment of the present invention.

[0025] Figure 3 This is a cross-sectional view of the stacked upper and lower shear boxes according to an embodiment of the present invention.

[0026] Figure 4 This is a partial cross-sectional view of the terracotta panel lateral control structure and the permeable stone lateral control structure provided in one embodiment of the present invention.

[0027] Explanation of reference numerals in the attached drawings: Upper shear box 101, Lower shear box 102, Unsaturated soil sample chamber 103, Structural material installation chamber 104, T-groove 105, Clay plate 106, Permeable stone 107, Water pressure interface 108, Gas-liquid interface 109, Moisture control chamber 110, Gas-liquid exchange chamber 111, Sealing ring 112, Removable pressure cap 113, Temperature-controlled water bath pipeline 114, Temperature-controlled medium inlet 115, Temperature-controlled medium outlet 116, Structural material support platform 117, Limiting wall 118, Temperature sensor 119, Distribution groove 120. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0029] It should be noted that although functional modules are divided in the system diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than the module division in the system or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned figures are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0030] Reference Figures 1 to 4 , Figure 1 A top view of the upper shear box provided in one embodiment of the present invention; Figure 2 This is a top view of the lower shear box provided in one embodiment of the present invention. Figure 3 This is a cross-sectional view of the stacked upper and lower shear boxes according to an embodiment of the present invention. Figure 4 This is a partial cross-sectional view of the terracotta panel lateral control structure and the permeable stone lateral control structure provided in one embodiment of the present invention.

[0031] In one embodiment, the soil-structure interface unsaturated temperature-controlled direct shear sample box includes an upper shear box 101 and a lower shear box 102. The upper shear box 101 is enclosed by a soil sample chamber wall to form an unsaturated soil sample chamber 103, which is used to contain unsaturated soil samples. With the shear direction as the first direction and the direction perpendicular to the shear direction in the horizontal plane as the second direction, the inner wall of the outer box is provided with T-shaped grooves 105 on the two opposite sides along the first direction. The T-shaped grooves 105 are used to cooperate with the shear drive component of the external direct shear loading device. Permeable stones 107 and terracotta plates 106 are respectively inlaid on the soil sample chamber wall. Both 7 and terracotta plate 106 have contact surfaces exposed to the unsaturated soil sample cavity for direct contact with the side of the unsaturated soil sample. Both permeable stone 107 and terracotta plate 106 are directly connected to the outside of the outer box through pipes. The lower shear box 102 is provided with a structural material mounting cavity 104 for mounting structural material samples. The upper shear box 101 and the lower shear box 102 are stacked. The lower surface of the unsaturated soil sample and the upper surface of the structural material sample form a soil-structure interface shear surface. The lower shear box 102 is provided with a temperature-controlled water bath pipe 114 inside the box. The temperature-controlled water bath pipe 114 is isolated from the structural material mounting cavity 104.

[0032] In use, the structural material sample can be first installed in the structural material installation cavity 104 of the lower shear box 102, and then the unsaturated soil sample can be installed in the unsaturated soil sample cavity 103 of the upper shear box 101, so that the terracotta plate 106 and the permeable stone 107 are in contact with the side of the unsaturated soil sample. Then, the water pressure interface 108 is connected to an external water pressure or water head control device, the gas-liquid interface 109 is connected to an external gas pressure, drainage or gas-liquid control device, and the temperature control medium inlet 115 and the temperature control medium outlet 116 are connected to an external circulating temperature control source.

[0033] During the saturation control stage, moisture can be transferred to the side of the unsaturated soil sample via the water pressure interface 108, internal pipelines, moisture control chamber 110, and terracotta plate 106; gas or moisture can be exchanged with the side of the unsaturated soil sample via the gas-liquid interface 109, internal pipelines, gas-liquid exchange chamber 111, and permeable stone 107. Since the terracotta plate 106 and permeable stone 107 directly constitute the lateral boundary of the unsaturated soil sample chamber 103, the saturation control path is short, and it is not necessary to transfer the soil sample from other humidification devices to the shear box. During the temperature control stage, the temperature control medium circulates through the temperature-controlled water bath pipeline 114 inside the lower shear box 102 and transfers heat to the soil-structure interface shear surface through the structural material sample. This temperature control method isolates the temperature control medium from the sample, reducing the impact of leakage on the soil sample's water content and interfacial contact state.

[0034] This application integrates the functions of unsaturated soil saturation control and interface temperature control into the independently replaceable direct shear sample box body. It can be directly adapted and used without modifying the main structure of the existing direct shear loading equipment, which greatly reduces the cost of test upgrades.

[0035] This application achieves direct moisture control and gas-liquid exchange from the side of the soil sample by laterally embedding clay plates 106 and permeable stones 107 into the upper shear box 101, directly forming the lateral boundary of the soil sample cavity. Compared with traditional end-face seepage and environmental humidity control methods, this significantly shortens the saturation control path. Furthermore, the soil sample can be loaded into the box once to complete the moisture balance and shear test, completely avoiding structural disturbance during sample transfer. Combined with the reverse staggered arrangement of the clay plates 106 and permeable stones 107 on both sides, moisture enters the unsaturated soil sample laterally through the clay plates 106, while gas or pore water is discharged laterally through the permeable stones 107. The side-to-side cross-flow paths, arranged in opposite directions, help reduce the local dominant channels and control dead zones formed by unilateral inflow, thereby effectively improving the control uniformity of the soil sample saturation field. The lower shear box 102 adopts a built-in temperature-controlled water bath pipeline 114 that is completely isolated from the structural sample installation cavity. It can precisely control the soil-structure interface temperature through the structural material side, and the temperature control medium will not contact the sample or interfere with the original water content of the soil sample. The shear drive connection structure and water-air control structure are arranged in different directions on different side walls of the box, with clear functional zoning and no interference between them. All structures are housed within the outer contour of the box, resulting in a compact structure and reliable sealing performance.

[0036] Furthermore, the lower shear box also includes: a structural material support platform 117 and a limiting wall 118 surrounding the structural material support platform 117. The limiting wall 118 is arranged around the outside of the structural material mounting cavity 104, and the structural material support platform 117 is located below the structural material mounting cavity 104. A temperature-controlled water bath pipeline 114 is arranged around the outside of the limiting wall 118. This arrangement of the temperature-controlled water bath pipeline 114 can better control the temperature at the location of the structural material mounting cavity 104, which helps to simulate more scenarios.

[0037] The upper surface of the structural material support platform 117 is flush with or 0.1 mm to 1 mm higher than the upper surface of the lower shear box 102, so that the upper surface of the structural material sample can form a soil-structure interface shear surface with the lower surface of the unsaturated soil sample.

[0038] The lower shear box 102 has a temperature-controlled medium inlet 115 and a temperature-controlled medium outlet 116 on its outer surface for connecting to an external circulating temperature control source. The temperature-controlled medium inlet 115 is connected to the liquid inlet of a temperature-controlled water bath pipe 114, and the temperature-controlled medium outlet 116 is connected to the liquid outlet of the temperature-controlled water bath pipe 114. The ability to connect the temperature-controlled medium inlet 115 and the temperature-controlled medium outlet 116 to an external circulating temperature control source facilitates accurate temperature control at the structural material mounting cavity 104. A temperature sensor 119 is installed inside the lower shear box 102 to detect the temperature inside the lower shear box 102, enabling real-time temperature adjustment.

[0039] The T-shaped groove 105 includes a wide groove section near the unsaturated soil sample chamber 103 and a narrow groove section that communicates with the wide groove section and extends to the outer side of the upper shear box 101. The T-shaped groove 105 facilitates connection to the shear drive component of an external direct shear loading device. The upper shear box 101 or the lower shear box 102 is provided with a positioning surface, connecting hole, guide groove, or limiting step that mates with the external direct shear loading device.

[0040] Among them, the control chamber connected to the terracotta plate 106 through the pipe is the moisture control chamber 110, and the control chamber connected to the permeable stone 107 through the pipe is the gas-liquid exchange chamber 111. Both the moisture control chamber 110 and the gas-liquid exchange chamber 111 are located on the outer surface of the upper shear box 101.

[0041] The temperature-controlled water bath pipeline 114 is located within the bottom or side wall of the lower shear box 102 and is at least partially arranged around the structural material mounting cavity 104. The temperature-controlled water bath pipeline 114 can be a ring-shaped pipeline, a serpentine pipeline, a U-shaped pipeline, or multiple parallel pipeline segments. The design of a ring-shaped pipeline, a serpentine pipeline, a U-shaped pipeline, or multiple parallel pipeline segments can improve the temperature uniformity within the bottom or side wall of the lower shear box 102 and enhance the reliability of the experiment.

[0042] Furthermore, the upper shear box 101 is provided with a detachable pressure cover 113 and a sealing ring 112 on the outside. The detachable pressure cover 113 is used to press the terracotta plate 106 or the permeable stone 107. The sealing ring 112 is pressed between the detachable pressure cover 113 and the upper shear box 101. A distribution groove 120 is provided between the detachable pressure cover 113 and the terracotta plate 106 and the permeable stone 107. A moisture regulation chamber 110 and a gas-liquid exchange chamber 111 are respectively provided in the distribution groove 120 corresponding to the terracotta plate 106 and the permeable stone 107.

[0043] The above is a detailed description of the preferred embodiments of the present utility model. However, the present utility model is not limited to the above-described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present utility model. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present utility model.

[0044] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. A soil-structure interface unsaturated temperature-controlled direct shear sample box, characterized in that, It includes an upper shear box and a lower shear box. The upper shear box includes an outer box body and a soil sample cavity wall disposed within the outer box body. The soil sample cavity wall encloses and forms an unsaturated soil sample cavity, which is used to contain unsaturated soil samples. With the shearing direction as the first direction and the direction perpendicular to the shearing direction in the horizontal plane as the second direction, the outer box body is provided with T-shaped grooves on the two opposite side walls along the first direction. The T-shaped grooves are used to cooperate with the shearing drive component of the external direct shear loading device. The walls of the soil sample chamber are inlaid with permeable stones and clay plates respectively. Both the permeable stones and the clay plates have contact surfaces exposed to the unsaturated soil sample chamber for direct contact with the sides of the unsaturated soil sample. Both the permeable stones and the clay plates are directly connected to the outside of the outer box through pipes. The lower shear box is provided with a structural material mounting cavity for mounting structural material samples. When the upper shear box and the lower shear box are stacked, the lower surface of the unsaturated soil sample and the upper surface of the structural material sample form a soil-structure interface shear surface. The lower shear box is provided with a temperature-controlled water bath pipeline, which is isolated from the structural material mounting cavity.

2. The soil-structure interface unsaturated temperature-controlled direct shear sample box according to claim 1, characterized in that, The lower shear box also includes: The structural material support platform and the limiting wall surrounding the structural material support platform are arranged around the outside of the structural material mounting cavity. The structural material support platform is located below the structural material mounting cavity, and the temperature-controlled water bath pipeline is arranged around the outside of the limiting wall.

3. The soil-structure interface unsaturated temperature-controlled direct shear sample box according to claim 2, characterized in that, The upper surface of the structural material support platform is flush with or 0.1 mm to 1 mm higher than the upper surface of the lower shear box, so that the upper surface of the structural material sample can form the soil-structure interface shear surface with the lower surface of the unsaturated soil sample.

4. The soil-structure interface unsaturated temperature-controlled direct shear sample box according to claim 1, characterized in that, The lower shear box has a temperature control medium inlet and a temperature control medium outlet on its outer surface for connecting to an external circulating temperature control source. The temperature control medium inlet is connected to the liquid inlet of the temperature control water bath pipeline, and the temperature control medium outlet is connected to the liquid outlet of the temperature control water bath pipeline.

5. The soil-structure interface unsaturated temperature-controlled direct shear sample box according to claim 4, characterized in that, A temperature sensor is installed inside the lower shear box to detect the temperature of the lower shear box.

6. The soil-structure interface unsaturated temperature-controlled direct shear sample box according to claim 1, characterized in that, The T-shaped groove includes a wide groove section near the unsaturated soil sample cavity and a narrow groove section that communicates with the wide groove section and extends to the outer side of the upper shear box.

7. The soil-structure interface unsaturated temperature-controlled direct shear test chamber according to claim 1, characterized in that, The upper shear box is also provided with a moisture control chamber and a gas-liquid exchange chamber. The terracotta plate is connected to the moisture control chamber through a pipe, and the permeable stone is connected to the gas-liquid exchange chamber through a pipe. Both the moisture control chamber and the gas-liquid exchange chamber are located on the outer surface of the upper shear box.

8. The soil-structure interface unsaturated temperature-controlled direct shear test chamber according to claim 1, characterized in that, The temperature-controlled water bath pipeline is located inside the bottom wall or side wall of the lower shear box and is at least partially arranged around the structural material mounting cavity; the temperature-controlled water bath pipeline is a ring pipeline, a serpentine pipeline, a U-shaped pipeline, or a multi-segment parallel pipeline.

9. A soil-structure interface unsaturated temperature-controlled direct shear test chamber according to claim 1, characterized in that, The upper shear box or the lower shear box is provided with a positioning surface, connecting hole, guide groove or limiting step to cooperate with an external direct shear loading device.

10. A soil-structure interface unsaturated temperature-controlled direct shear test chamber according to claim 1, characterized in that, The upper shear box is provided with a detachable pressure cover and a sealing ring on the outside. The detachable pressure cover is used to press the clay plate or the permeable stone, and the sealing ring is pressed between the detachable pressure cover and the upper shear box.

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