Soil direct shear multi-parameter detection device and detection method

Abstract

The invention provides a soil direct shear multi-parameter detection device and method, the soil direct shear multi-parameter detection device comprises an upper shear box and a lower shear box, the upper shear box comprises two transverse push plates and two longitudinal side plates which are connected; a push-pull device is arranged on the side surface of the upper shear box, so that the upper shear box displaces relative to the lower shear box; a pressure sensor and a linear displacement sensor are also arranged on the side surface of the upper shear box; the lower shear box is arranged below the upper shear box and is fixedly connected with the experiment table, and the size of the lower shear box is matched with that of the upper shear box; a detachable rectangular flat plate for generating sliding friction is arranged at the top end of the upper shear box, or a detachable round roller for generating rolling friction is arranged at the top end of the upper shear box. The method has the beneficial effects that detection of various soil parameters can be completed in a short time, the detection period is greatly shortened, physical and chemical properties such as sliding friction coefficients and rolling friction coefficients between the soil and different materials can be measured, and comprehensive soil characteristic analysis is provided.

Description

Technical Field

[0001] The present invention relates to the technical field of detection devices and inspection and testing services, and in particular to a soil direct shear multi-parameter detection device and a detection method. Background Art

[0002] As an important tool for studying soil science, the soil information database can provide rich and multi-dimensional soil information, which covers many aspects of soil physics, chemistry, biology and environment. Soil mechanical properties and soil physicochemical properties are the core components of soil information. In-depth mining of this information has important guiding significance for regulating soil environment, optimizing tillage tools and farming methods. However, the soil information database has problems such as a large number of soil samples, large differences in soil properties, and a small amount of soil available for testing. It is difficult to efficiently and accurately obtain effective soil information, especially soil mechanical properties with a large number of parameters.

[0003] At present, conventional soil direct shear detection devices can accurately detect soil mechanical property parameters, but they generally have problems such as single detection parameters, large amount of soil, long time consumption, and difficult operation; it is difficult to meet the detection needs of rapid and accurate acquisition of soil information under the background of big data. Therefore, the development of a soil direct shear detection device with multiple parameters and less soil consumption is of great significance for the establishment of soil information big data.

[0004] The existing soil shear strength measuring device (CN117705609A) is mainly used to obtain the shear strength value of rooted soil indoors. It can be applied to shear strength detection under different working conditions such as underwater rooted soil, saturated soil, and soil with specific moisture content. However, the sample box of the device has a size of 500mm*500mm and a depth of 400mm, and the detection soil consumption is relatively large. Although it can realize accurate detection of a certain mechanical property parameter, it is often difficult to meet the needs of the soil sample library for low soil consumption and rapid detection of multiple soil mechanical property parameters. Summary of the invention

[0005] In order to solve the problems of single detection parameters, large amount of soil and long time consumption of current soil direct shear detection devices; The invention provides a soil direct shear multi-parameter detection device, comprising an upper shear box and a lower shear box, the upper shear box comprising two horizontal push plates and two longitudinal side plates connected to form a push-pull device on the side of the upper shear box to make the upper shear box displace relative to the lower shear box, and a pressure sensor and a linear displacement sensor are also arranged on the side of the upper shear box; the lower shear box is arranged below the upper shear box and fixedly connected to a laboratory table, and the size of the lower shear box is adapted to the upper shear box; a detachable rectangular flat plate for generating sliding friction is arranged on the top of the upper shear box, or a detachable roller for generating rolling friction is arranged on the top of the upper shear box.

[0006] As a preferred solution, a screw hole is provided at the top of the push plate, and first hanging ears are provided at both sides of the side plate. Screw holes are provided at positions corresponding to the first hanging ears and bolts are provided to fix the push plate and the side plate.

[0007] As a preferred solution, the lower shear box is surrounded by four L-shaped side panels to form a quadrilateral container, and the side panels are fixedly connected to the ground by bolts.

[0008] As a preferred solution, it also includes a slide rail, which is composed of two parallel guide rails and fixed plates fixed at both ends of the guide rails. Guide plates are arranged on both sides of the upper shear box and are slidably arranged on the guide rails.

[0009] As a preferred solution, the push-pull device includes a servo motor and a spiral push rod. The servo motor is fixedly arranged on the fixed plate. One end of the spiral push rod is connected to the servo motor, and the other end is connected to the upper shear box.

[0010] As a preferred solution, the roller and the rectangular flat plate are provided with support rods and connecting parts are provided on both sides of the support rods to connect the shear box, the connecting parts include a second hanging ear and a connecting rod, the second hanging ear is detachably connected to the push plate, and the two ends of the connecting rod are respectively hinged to the second hanging ear and the support rod.

[0011] In addition, the present invention also provides a soil direct shear multi-parameter detection method, comprising the following steps: Shear parameter detection: Push the pressed soil sample along the upper shear box so that the sample is placed in the middle of the upper and lower shear boxes, place a pressing block on the upper surface of the soil, open the push-pull device to push the upper shear box 6mm, close the push-pull device and remove the pressing block, open the push-pull device to pull the upper shear box back to the initial position; take out the tested soil sample and put in a soil sample with the same properties and size, place a pressing block twice the weight of the previous pressing block on the upper surface of the soil, repeat the above detection operation, and calculate the shear strength, internal friction angle and cohesion through the data obtained by the pressure sensor and the linear displacement sensor; Sliding friction coefficient detection: After the second shearing is completed, the push-pull device pulls the upper shear box back to the initial position, and there is no need to remove the soil; remove the side plate, remove the soil above the lower shear box and flatten the remaining soil, and then reinstall the side plate; hinge the rectangular plate and the connecting piece and assemble it with the upper shear box, adjust the position of the connecting piece so that the rectangular plate fits the soil surface; turn on the push-pull device to push the upper shear box 10mm; calculate the sliding coefficient between the soil and the plate material through the data obtained by the pressure sensor and the linear displacement sensor and the mass of the rectangular plate; Rolling friction coefficient detection: remove the connecting parts and replace the rectangular plate with a roller, adjust the position of the connecting parts so that the roller fits the soil surface, turn on the push-pull device to pull the upper shear box back to the initial position, and calculate the rolling friction coefficient between the soil and the roller material through the data obtained by the pressure sensor and the linear displacement sensor and the mass of the roller.

[0012] As a preferred solution, after each detection step is completed, the pressure sensor and the linear displacement sensor are cleared.

[0013] The beneficial effects of the present invention are: The present invention reduces the amount of soil samples required by optimizing the design of the detection device, thereby reducing the experimental cost and the demand for resources. Secondly, the detection device of the present invention can complete the detection of various soil parameters in a short time, greatly shortening the detection cycle, so that the results can be quickly fed back, providing instant data support for engineering decision-making and research. Finally, the present invention can not only detect the mechanical properties of the soil such as shear strength, internal friction angle and cohesion, but also measure the physical and chemical properties such as the sliding friction coefficient and rolling friction coefficient between the soil and different materials, providing a comprehensive soil property analysis platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, wherein Figure 1 A schematic diagram of the structure of the present invention.

[0015] Figure 2 A schematic structural diagram of the present invention from another angle.

[0016] Figure 3 A schematic structural diagram of the bottom of the present invention.

[0017] Figure 4 Schematic diagram of shear parameter detection according to the present invention.

[0018] Figure 5 Schematic diagram of the sliding friction coefficient detection of the present invention.

[0019] Figure 6 Schematic diagram of the rolling friction coefficient detection of the present invention.

[0020] The reference numerals in the accompanying drawings are: 201. Guide rail; 202. Servo motor; 203. Fixed plate; 204. Side panel; 205. Push plate; 206. Side panel; 207. First hanging ear; 208. Screw push rod; 209. Pressure sensor; 210. Linear displacement sensor; 211. Support rod; 212. Second hanging ear; 213. Connecting rod; 214. Roller; 215. Rectangular plate; 216. Guide plate. DETAILED DESCRIPTION

[0021] To illustrate the features of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0022] Embodiment 1: See also Figures 1 to 3 An embodiment of the present invention is a soil direct shear multi-parameter detection device, which is composed of a measuring system and a slide rail system. The measuring system is driven by a push-pull device to slide in the slide rail system, wherein the measuring system includes an upper shear box and a lower shear box, and the cross-section of the upper shear box and the lower shear box is a square of 6cmx6cm.

[0023] The upper shear box includes two horizontal push plates 205 and two longitudinal side plates 206 connected together. A screw hole is opened at the top of the push plate 205, and first hanging ears 207 are set on both sides of the side plates 206. Screw holes are set at the corresponding positions of the first hanging ears 207 and bolts are set to fix the push plate 205 and the side plates 206. When placing soil samples, they can be placed directly from above. When taking out the soil samples, the side plates 206 are removed and the soil is taken out.

[0024] A push-pull device is arranged on the side of the upper shear box to displace the upper shear box relative to the lower shear box. The push-pull device includes a servo motor 202 and a screw push rod 208. One end of the screw push rod 208 is connected to the servo motor 202, and the other end is connected to the upper shear box. A pressure sensor 209 and a linear displacement sensor 210 are also arranged on the side of the upper shear box. The push plate 205 is provided with a countersunk hole and connected to the pressure sensor 210 by bolts to avoid damaging the soil sample block inside the shear box. The soil is subjected to shear force through the relative displacement of the upper shear box and the lower shear box, and relevant data is collected through the pressure sensor 209 and the linear displacement sensor 210, so as to calculate the mechanical properties of the soil.

[0025] The lower shear box is arranged below the upper shear box and is fixedly connected to the laboratory bench. The size of the lower shear box is adapted to the upper shear box. The lower shear box is surrounded by four L-shaped side panels 204 to form a quadrilateral container. The side panels 204 are fixedly connected to the ground with bolts. After use, the bolts are removed and the side panels 204 are taken down for cleaning.

[0026] In particular, in this embodiment, a detachable rectangular flat plate 215 for generating sliding friction is provided at the top of the upper shear box, or a detachable roller 214 for generating rolling friction is provided at the top of the upper shear box, which are respectively used to measure the sliding friction and rolling friction of the soil. The rectangular flat plate 215 and the roller 214 are connected to the upper shear box in such a way that the roller 214 and the rectangular flat plate 215 are provided with a support rod 211 and connecting parts are provided on both sides of the support rod to connect the upper shear box, the connecting parts include a second hanging ear 212 and a connecting rod 213, the second hanging ear 212 is detachably connected to a push plate 205, and the two ends of the connecting rod 213 are respectively hinged to the second hanging ear 212 and the support rod 211. Through this connection method, the rectangular flat plate 215 and the roller 214 can be removed by removing the bolts, and the angle of the connecting parts can be adjusted so that the rectangular flat plate 215 and the roller 214 are attached to the soil surface, so that the measurement result is more accurate.

[0027] The slide rail system is composed of two parallel guide rails 201 and fixed plates 203 fixed at both ends of the guide rails. The servo motor 202 is fixed on the fixed plate 203. Guide plates 216 are arranged on both sides of the upper shear box and are slidably arranged on the guide rails 201. In this embodiment, the two sides of the push plate 205 are extended to serve as guide plates 216. Guide rail holes are opened on the guide plates 216 to allow the guide rails to pass through, so that the servo motor 202 drives the measuring system to slide on the slide rail system.

[0028] In this embodiment, the measuring system is organically integrated with the upper shear box, the lower shear box, the rectangular plate and the roller, so that the device has the basis for detecting various soil mechanical parameters.

[0029] Embodiment 2: See also Figures 4 to 6 This embodiment provides a soil direct shear multi-parameter detection method, which allows operators to use the device of embodiment 1 more efficiently to continuously measure shear parameters, sliding friction and rolling friction, and specifically includes the following steps: S1. Shear parameter detection: Push the pressed sand sample along the upper shear box so that the sample is placed in the middle of the upper and lower shear boxes. Place a 2kg block on the upper surface of the soil. The normal positive pressure σ1 = m1*9.81*10 -3 / (S*10 -4 )=5.45 KN / m 2 , open the push-pull device and push the upper shear box 6mm at a shear speed of 1mm / min. Figure 4 , pause the push-pull device and remove the pressure block, open the push-pull device to pull the upper shear box back to the initial position, and calculate the shear strength τ1 according to the reading of the pressure sensor, which is 26.3 KN / m 2 ; Take out the tested soil sample and put in a soil sample with the same properties and size. Place a 4kg pressure block on the upper surface of the soil. The normal pressure σ2= m2*9.81*10 -3 / (S*10 -4 )=10.9 KN / m 2 Repeat the above detection operation, and calculate the shear strength τ2 as 26.3KN / m through the data of pressure sensor 209 2 ; Substituting σ1, τ1; σ2, τ2 into the Coulomb equation, τ=c+σtanφ, we can get the cohesion c as 21.4KN / m 2 , the friction angle φ is 41.8°; S2. Sliding friction coefficient test: After the second shearing is completed, the push-pull device pulls the upper shear box back to the initial position, and there is no need to remove the soil; remove the side plate 206, remove the soil above the lower shear box and flatten the remaining soil, and replace the side plate 206; assemble the 65Mn material and the rectangular flat plate 215 weighing 128g with the connecting piece by hinge and connect it to the upper shear box, adjust the position of the connecting piece so that the rectangular flat plate 215 fits the soil surface. Figure 5 ; The push-pull device is turned on with a push plate speed of 0.1 mm / s, and the upper shear box is pushed 10 mm. The linear displacement sensor 210 records the running distance; the sliding friction coefficient between the soil and the flat plate material is calculated by the data obtained by the pressure sensor 209 and the linear displacement sensor 210 and the mass of the rectangular plate 215; S3. Testing of rolling friction coefficient: Remove the connector and replace the rectangular plate 215 with a 65Mn material and a roller 214 weighing 240 g. Adjust the position of the connector so that the roller 214 fits the soil surface. Figure 6 , open the push-pull device to pull the upper shear box back to the initial position at a push plate speed of 0.1mm / s, the linear displacement sensor 210 records the running distance, and the motor stops when the specified distance is reached. The rolling friction coefficient between the soil and the roller material is calculated to be 0.17 through the data obtained by the pressure sensor 209 and the linear displacement sensor 210 and the mass of the roller 214.

[0030] In particular, in order to make the detection result more accurate and avoid the influence of the error of the device on the detection result, this embodiment performs a zeroing operation on the pressure sensor 209 and the linear displacement sensor 210 after each detection step is completed.

[0031] The above embodiments and drawings are only used to illustrate the technical solutions of the present invention, and are not intended to limit the present invention. The present invention is described in detail with reference to the preferred embodiments. It should be understood by those skilled in the art that any changes, modifications, additions or substitutions made by those skilled in the art within the essential scope of the present invention do not deviate from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention. Other related technical structures not fully disclosed in the present invention are prior art in the art.

Claims

1. A soil direct shear multi-parameter detection device, comprising an upper shear box and a lower shear box, characterized in that: The upper shear box comprises two transverse push plates (205) and two longitudinal side plates (206) connected together; a push-pull device is arranged on the side of the upper shear box to enable the upper shear box to move relative to the lower shear box; a pressure sensor (209) and a linear displacement sensor (210) are also arranged on the side of the upper shear box; The lower shear box is arranged below the upper shear box and is fixedly connected to the ground, and the size of the lower shear box is adapted to the upper shear box; A detachable rectangular flat plate (215) for generating sliding friction is arranged at the top of the upper shear box, or a detachable round roller (214) for generating rolling friction is arranged at the top of the upper shear box.

2. The soil direct shear multi-parameter detection device according to claim 1, characterized in that: A screw hole is provided at the top of the push plate (205), and first hanging ears (207) are provided on both sides of the side plate (206). Screw holes are provided at positions corresponding to the first hanging ears (207) and bolts are provided to fix the push plate (205) and the side plate (206).

3. The soil direct shear multi-parameter detection device according to claim 1, characterized in that: The lower shear box is surrounded by four L-shaped side panels (204) to form a quadrilateral container, and the side panels (204) are fixedly connected to the ground by bolts.

4. The soil direct shear multi-parameter detection device according to claim 1, characterized in that: It also includes a slide rail, which is composed of two parallel guide rails (201) and fixed plates (203) fixedly arranged at both ends of the guide rails. Guide plates (216) are arranged on both sides of the upper shear box and are slidably arranged on the guide rails (201).

5. The soil direct shear multi-parameter detection device according to claim 4, characterized in that: The push-pull device comprises a servo motor (202) and a spiral push rod (208); the servo motor (202) is fixedly arranged on the fixed plate (203); one end of the spiral push rod (208) is connected to the servo motor (202), and the other end is connected to the upper shear box.

6. The soil direct shear multi-parameter detection device according to claim 1, characterized in that: The roller (214) and the rectangular flat plate (215) are provided with a support rod (211), and connecting pieces are provided on both sides of the support rod to connect to the shear box, the connecting piece comprises a second hanging ear (212) and a connecting rod (213), the second hanging ear (212) is detachably connected to the push plate (205), and the two ends of the connecting rod (213) are respectively hinged to the second hanging ear (212) and the support rod (211).

7. A soil direct shear multi-parameter detection method, characterized in that: The following steps are involved: S1. Shear parameter detection: The pressed soil sample is pushed along the upper shear box so that the sample is placed in the middle of the upper and lower shear boxes, a pressing block is placed on the upper surface of the soil, the push-pull device is turned on to push the upper shear box by 6 mm, the push-pull device is turned off and the pressing block is removed, and the push-pull device is turned on to pull the upper shear box back to the initial position; the tested soil sample is taken out and a soil sample with the same properties and size is placed, a pressing block twice the weight of the previous pressing block is placed on the upper surface of the soil, and the above-mentioned testing operation is repeated, and the soil shear strength, internal friction angle and cohesion are calculated using the data obtained by the pressure sensor (209) and the linear displacement sensor (210); S2. Sliding friction coefficient test: After the second shearing is completed, the push-pull device pulls the upper shear box back to the initial position without removing the soil; the side plate (206) is removed, the soil above the lower shear box is removed and the remaining soil is flattened, and then the side plate (206) is reinstalled; the rectangular plate (215) is hingedly assembled with the connecting piece and connected to the upper shear box, and the position of the connecting piece is adjusted so that the rectangular plate (215) fits the soil surface; the push-pull device is turned on to push the upper shear box by 10 mm; the sliding friction coefficient between the soil and the plate material is calculated using the data obtained by the pressure sensor (209) and the linear displacement sensor (210) and the mass of the rectangular plate (215); S3. Rolling friction coefficient test: The connecting piece is removed and the rectangular plate (215) is replaced by a roller (214). The position of the connecting piece is adjusted so that the roller (214) fits the soil surface. The push-pull device is turned on to pull the upper shear box back to the initial position. The rolling friction coefficient between the soil and the roller is calculated based on the data obtained by the pressure sensor (209) and the linear displacement sensor (210) and the mass of the roller (214).

8. The soil direct shear multi-parameter detection method according to claim 7, characterized in that: After each detection step is completed, the pressure sensor (209) and the linear displacement sensor (210) are cleared.

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