Coarse-particle soil direct shear and repeated shear test equipment and test method

Abstract

The invention relates to coarse-particle soil direct shear and repeated shear test equipment and a test method, and relates to the field of soil mechanics test equipment. According to the technical scheme, the friction detection and rolling mechanism outputs horizontal shearing force through the horizontal servo motor, the shearing force deducts extra friction force generated by related rolling parts through the friction sensor, and the reliability of test data is improved; the V-shaped embedded guide rail is matched with the V-shaped bearing seat, so that chipping abrasion is avoided, the shearing box mechanism is limited to only do one-way reciprocating motion, lateral movement deflection is prevented, vertical stress uniformity is guaranteed, the service life is prolonged, the maintenance cost is reduced, and automatic alignment can be achieved to improve efficiency; the conveying mechanism provides power and is matched with a motor and the like to achieve automatic operation, labor intensity and cost are reduced, and the automation degree is high; the shearing box mechanism in modular design is convenient to maintain, sample loading boxes of different specifications and types can be replaced, subsequent maintenance is facilitated, and the experiment efficiency and the resource utilization rate are improved; the lifting foot margin mechanism is convenient to install, and a fixed floor does not need to be transformed.

Description

Technical Field

[0001] This invention relates to the field of soil mechanics testing equipment, and in particular to a test device and method for direct shear and repeated shear tests on coarse-grained soil. Background Technology

[0002] The working principle of the direct shear test apparatus is based on the direct shear test. Specifically, different vertical pressures are applied to the coarse-grained sample to achieve consolidation, and then a horizontal shear force is applied under the corresponding vertical stress conditions until the sample fails. In this way, the shear strength of the coarse-grained sample on a fixed shear plane can be directly measured, and then the internal friction angle and cohesion of the soil can be determined according to Coulomb's law.

[0003] The existing operating procedure is as follows: First, the lower shear box is suspended on the roller rack. A slit ring and steel balls are placed on the lower shear box to control the size of the shear slit. Then, the upper shear box is placed, ensuring concentricity between the upper and lower boxes and positioning them with fixing pins. The weighed sample is layered into the shear box, with each layer controlled to a predetermined height using methods such as compaction, vibration, or static pressure. A permeable plate and pressure plate are placed sequentially on the sample surface, ensuring alignment during installation. The pressure plate is leveled with a spirit level, and the upper and lower reaction steel beams are also kept horizontal. Two to four vertical dial indicators are installed, and the vertical drive shaft is slowly started until all components contact, at which point the initial deformation reading is recorded. A horizontal dial indicator or displacement gauge is installed, ensuring the force line of the horizontal drive shaft passes through the center of the shear surface. The horizontal drive shaft is then slowly started until it contacts the force point of the lower shear box and stops.

[0004] Taking the slow shear test as an example, an impermeable steel plate of the same thickness as the permeable plate is placed at the contact point between the upper and lower surfaces of the specimen. After applying a vertical load to the specimen, the specimen is considered to have completed the consolidation process under vertical pressure after 24 hours of consolidation. This state is maintained throughout the test. The fixing pins of the upper and lower shear boxes are removed and the slit ring is taken off. The readings of the vertical and horizontal force gauges, dial gauges, etc. are recorded. The horizontal drive shaft and stopwatch are started. When the shear stress reading reaches a stable state or shows a significant retreat, it indicates that the specimen has been sheared. If the shear stress reading continues to increase, the shear deformation needs to reach 60 mm or 1 / 15 to 1 / 10 of the specimen's side length. The reading of the load sensor or force gauge is recorded every 1 mm, and the vertical displacement reading is recorded as needed until the specimen is sheared. After the test, the dial gauge or displacement gauge, horizontal load, vertical load, and loading equipment are removed in time. The shear surface is briefly described as needed. At the same time, a specimen near the shear surface is taken to determine its moisture content and particle size distribution after shearing.

[0005] However, existing technologies have many obvious drawbacks: Firstly, large direct shear apparatuses obtain the shear strength of coarse aggregates by measuring the frictional force between soil and rock particles at the shear surface. During large direct shear tests, due to the large vertical load applied, the frictional force generated between the shear box and the base and upper pressure plate during shearing is usually difficult to ignore. However, this additional frictional force is not deducted when calculating the soil shear strength, resulting in the measured soil shear strength being greater than the actual value. Existing technologies have not yet been able to properly solve this problem (this invention effectively eliminates the error introduced by the frictional force of the test device itself by adding a sensor between the V-shaped bearing seat and the lower shear box above it, significantly improving the test accuracy).

[0006] Secondly, during the test, sample debris inevitably falls below the shear box. In addition, dust, sand and other impurities easily adhere to the surface of the rollers in the geotechnical laboratory environment, which can easily cause contamination of the roller surface. Once impurities enter the inside of the roller bearing, they can easily cause the roller to jam and run poorly, thus affecting the reliability of the test results. During long-term wear and tear, foreign objects that penetrate into the roller will accelerate the deterioration of the roller's performance, significantly shorten its service life and reduce the test accuracy (this invention avoids the inherent problems of traditional bearing solutions through a novel V-shaped bearing mechanism).

[0007] Thirdly, according to geotechnical testing specifications, the shear box needs to perform unidirectional and reciprocating motion during the direct shear test. However, existing direct shear testers place the lower shear box directly on the roller rack, making it difficult to effectively restrict other degrees of freedom besides the horizontal direction. If existing technology is used to restrict these degrees of freedom, it will further increase the friction between the lower shear box and the base (traveling parts and slide). If it is not restricted, it will lead to uneven normal pressure on coarse particle samples during the shearing process. (This invention, through the interlocking design of V-shaped guide rail and V-shaped bearing seat, not only reduces the friction between the traveling parts and the slide, improves the test accuracy and equipment service life, but also effectively restricts other degrees of freedom of the lower shear box besides the horizontal direction without adding extra sliding friction.) Summary of the Invention

[0008] The purpose of this invention is to provide a test device and method for direct shear and repeated shear tests on coarse-grained soil, so as to solve the problems existing in the prior art.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a device for direct shear and repeated shear testing of coarse-grained soil, comprising: A shearing box mechanism includes a lower base plate, a lower shearing box mounted on the lower base plate, and an upper shearing box mounted on the lower shearing box. It is used to contain coarse particle samples and to perform shearing operations through the relative movement of the lower shearing box and the upper shearing box. Friction detection and rolling mechanism, which includes an upper mounting plate and a lower mounting plate. The upper mounting plate is connected to the guide block and the upper mounting rail at the bottom of the shear box mechanism through a guide fixing block and a lower fitting guide rail, respectively. A dustproof cloth cover is installed between the upper mounting plate and the lower mounting plate through a cloth cover pressure plate. A friction sensor is also provided between the upper mounting plate and the lower mounting plate. A conveying mechanism, connected to the chain support of the friction detection and rolling mechanism via a chain, is used to drive the friction detection and rolling mechanism to move along the slide rail; and A horizontal loading mechanism and a vertical loading mechanism, wherein the horizontal loading mechanism is mounted on one side of the vertical loading mechanism; The horizontal loading mechanism is used to apply a horizontal shearing force to the lower shear box and, in conjunction with a sensor, detects the horizontal force and displacement; the vertical loading mechanism is used to apply a vertical pressure to the coarse particle sample inside the shear box mechanism and, in conjunction with a sensor, detects the vertical displacement and pressure.

[0010] In some implementations, the shear box mechanism further includes: The following components are included: an upper wear-resistant plate installed inside the upper shear box; a sliding seat installed outside the upper shear box; a sliding shaft passing through the vertical shaft hole of the sliding seat; a rotating plunger passing through the horizontal shaft hole of the sliding seat; a lower wear-resistant plate installed inside the lower shear box; a guide seat installed outside the lower shear box; a lower bottom plate wear-resistant plate installed on the lower bottom plate; a barrier installed around the lower bottom plate; a flexible tube elastically disposed inside the shear box mechanism; a sealing gasket installed between the barrier and the lower bottom plate; a support installed on one side of the guide block; angle irons for supporting feet installed on both sides of the bottom of the lower bottom plate; and an overflow port disposed at the bottom of the lower bottom plate and connected to the inside of the shear box mechanism. The rotating plunger is used to fix the position of the sliding shaft in the sliding seat. The guide seat is positioned corresponding to the sliding seat. The bottom end of the sliding shaft is inserted into the guide seat. The bottom of the tendon tube is tightly fitted onto the outer periphery of the lower base plate. The top of the tendon tube flips over the upper shear box and is tightly fitted onto the top outer periphery of the upper shear box through the flange.

[0011] In some implementations, a stacking plate, a pad, and a gap insert are provided between the upper shear box and the lower shear box. The upper and lower parts of the gap insert are threadedly connected to the upper shear box and the lower shear box respectively through a mesh knob and a pad. A fixing plate is installed at the right angle between the lower shear box and the lower base plate. An adjusting threaded block is installed on the side of the fixing plate away from the lower shear box. An adjusting screw passes through the adjusting threaded block and abuts against the fixing plate. A fork pin seat is also installed on one side of the lower shear box. Lifting rings are also installed near the four corners of the lower base plate.

[0012] In some implementations, the friction detection and rolling mechanism also includes: The following components are mounted on the upper mounting plate: a friction roller conveyor; two friction mounting seats respectively mounted on the opposite surfaces of the upper and lower mounting plates; a friction sensor mounted between the two friction mounting seats; a friction bearing seat mounted on the lower mounting plate; a friction bearing shaft passing through the bearing hole of the friction bearing seat; a friction bearing mounted on the front end of the friction bearing shaft; an oil nozzle mounted on the end of the friction bearing shaft and connected to the internal oil passage of the friction bearing shaft; a tightening seat mounted on the upper mounting plate and located on one side of the friction bearing seat; a roller seat mounted on the lower mounting plate; a roller bearing mounted in the bearing hole of the roller seat; a magnetic head mounting plate mounted on the bottom of the lower mounting plate; a magnetic head mounted on the magnetic head mounting plate; a V-shaped bearing seat mounted on the lower mounting plate; a V-shaped bearing shaft mounted in the shaft hole of the V-shaped bearing seat; a V-shaped bearing fixed to the shaft end of the V-shaped bearing shaft by a locking nut; and an anti-collision sensing block and a proximity sensing plate mounted on the bottom of the lower mounting plate. The location of the friction sensor is protected from dust contamination by a sealing plate, rubber gasket, and sealing plate; the tightening seat can slide the friction bearing seat, so that the side wall of the friction bearing is constrained to move with the friction roller.

[0013] In some implementations, the conveying mechanism includes: The following components are included: a conveyor pipe mounted on a fixed bracket by a fixed angle iron; a chain guide rail mounted on the conveyor pipe for guiding the chain; an idler shaft mounted on one end and the middle of the conveyor pipe by an idler lock plate; a toothless idler wheel sleeved on the idler shaft and meshing with the chain; a motor mounting plate mounted on the conveyor pipe; a motor mounted on the motor mounting plate; a bearing housing mounting plate connected to the motor mounting plate by a reinforcing rib; a bearing housing mounted on the bearing housing mounting plate; an end cover mounted on the outside of the bearing housing; a spacer and a drive sprocket located on the side of the bearing housing mounting plate away from the bearing housing; an idler wheel mounted on the other end of the conveyor pipe; and a drive shaft that passes sequentially through the drive sprocket, the spacer, and the bearing housing. A top block is installed below the idler shaft in the middle of the conveying pipe to support the idler shaft, so that the toothless idler lifts the chain away from the conveying pipe; the idler and the drive sprocket mesh with the chain, and the toothless idler is in direct contact with the chain.

[0014] In some implementations, a proximity fixing sheet metal is also installed on the conveying pipe, and a metal sensor corresponding to the proximity sensing plate of the friction detection and rolling mechanism is installed on the proximity fixing sheet metal; a cover housing that encloses the chain, the drive sprocket and the toothless idler wheel is also installed on the conveying pipe; the slide is installed on the fixed bracket, and an anti-collision block corresponding to the anti-collision sensing block of the friction detection and rolling mechanism is installed on the slide.

[0015] In some implementations, the horizontal loading mechanism includes: A push plate mounted on a push plate mounting base, a horizontal servo motor mounted on the push plate, a load mounting plate mounted on the output end of the horizontal servo motor, a horizontal pressure sensor mounted on the load mounting plate, a pin hole end mounted on the horizontal pressure sensor via a locking sleeve, and a connector mounted on the push plate mounting base and connected to the vertical base of the vertical loading mechanism. The pin of the vertical loading mechanism is inserted into the pin hole end and the fork pin seat of the shear box mechanism to realize the consolidation and shear test of the soil sample.

[0016] In some implementations, the vertical loading mechanism includes: A pin seat mounted on a vertical base, a pin inserted into the pin hole of the pin seat, a horizontal displacement sensor mounted on the vertical base, a V-shaped fitting guide rail mounted on the vertical base and corresponding to the V-shaped bearing of the friction detection and rolling mechanism, a magnetic rail mounted on the vertical base and corresponding to the magnetic head of the friction detection and rolling mechanism, columns mounted on both sides of the vertical base, a support beam mounted between the two columns, a crossbeam mounted on the top of the two columns, a vertical displacement sensor mounted on the crossbeam via a vertical displacement sensor mounting plate, a vertical servo motor mounted on the crossbeam, a fixed load upper plate mounted on the output end of the vertical servo motor, a fixed load lower plate connected to the fixed load upper plate via a vertical pressure sensor, and a pressure transmission plate mounted at the bottom of the fixed load lower plate. The bottom of the pressure transmission plate is also equipped with a pressure transmission wear-resistant plate, which is used to uniformly transmit the pressure applied by the vertical servo motor to the coarse particle sample, while reducing the wear of the pressure transmission plate.

[0017] In some implementations, the coarse-grained soil direct shear and repeated shear test equipment further includes: The lifting foot mechanism includes a shock-absorbing and fixed chassis, a lifting shaft mounted on the shock-absorbing and fixed chassis, a leveling block threaded onto the lifting shaft, a locking ring threaded onto the lifting shaft and abutting against the leveling block, and a fixing screw mounted on the top of the lifting shaft via a large washer. The horizontal loading mechanism and the vertical loading mechanism are both equipped with lifting foot mechanisms at their bottoms. The fixing screws are respectively connected to the push plate fixing seat of the horizontal loading mechanism and the vertical base of the vertical loading mechanism. The shock-absorbing fixing chassis of the lifting foot mechanism is installed on the fixed floor.

[0018] Secondly, the present invention provides a method for direct shear and repeated shear tests on coarse-grained soil, wherein the method is applied in the coarse-grained soil direct shear and repeated shear test equipment as described above, and the method includes: S1. Consolidation Test: The conveying mechanism drives the shear box mechanism into the vertical loading mechanism. The roller bearing disengages from the slide rail, and the V-bearing rolls along the V-shaped interlocking guide rail. The anti-collision sensing block and the magnetic head contact the horizontal displacement sensor and the magnetic rail respectively to measure the displacement. After reaching the position, the conveying mechanism stops, keeping the sliding shaft between the upper and lower shear boxes in the inserted state to prevent relative movement between the upper and lower shear boxes during the consolidation process. Switch to consolidation mode, and the vertical servo motor drives the pressure plate to apply the specified consolidation pressure. When the pressure value output by the vertical pressure sensor is stably maintained at the specified consolidation pressure, and the vertical displacement output by the vertical displacement sensor no longer changes within a certain period of time, the consolidation ends. S2. Shear test: Loosen the mesh knob of the shear box mechanism to let the pad fall off, remove the gap insert plate, loosen the rotating plunger to pull the sliding shaft to the upper position and lock it, so that it is separated from the lower shear box; the horizontal servo motor drives the horizontal pressure sensor, which in turn drives the pin hole end, the fork pin seat and the lower shear box in sequence. The friction force generated by the upper mounting plate and the lower mounting plate is output by the friction sensor and the horizontal servo motor together; when the horizontal displacement reaches the threshold or the sample is sheared, stop, pull out the pin, control the conveying mechanism to make the proximity sensing plate close to the metal sensor and stop, loosen the guide fixing block bolt, and use the lifting ring to lift the shear box mechanism to the cleaning area for cleaning and storage.

[0019] The beneficial effects of the technical solution provided by this invention include at least the following: The friction detection and rolling mechanism of this technical solution outputs horizontal shearing force through a horizontal servo motor. The shearing force is deducted by a friction sensor from the additional friction generated by the rolling components, improving the reliability of the test data. The V-shaped interlocking guide rail and V-shaped bearing seat cooperate to avoid debris wear, limit the shear box mechanism to unidirectional reciprocating motion, prevent lateral displacement and deflection, ensure uniform vertical stress, extend service life, reduce maintenance costs, and can also automatically align to improve efficiency. The conveying mechanism provides power and works with the motor to achieve automatic operation, reducing labor intensity and costs, and achieving a high degree of automation. The modular design of the shear box mechanism is easy to maintain and can replace sample loading boxes of different specifications and types, facilitating subsequent maintenance and improving experimental efficiency and resource utilization. The lifting foot mechanism is easy to install and does not require modification of the fixed floor. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0021] Figure 1 An overall axonometric view of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention is shown.

[0022] Figure 2 The diagram shows an upper axial side view of the shear box mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention.

[0023] Figure 3 The diagram shows a lower axonometric view of the shear box mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention.

[0024] Figure 4 This image shows a partial axial sectional view of the friction detection and rolling mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention.

[0025] Figure 5 The image shows a lower axial side view of the friction detection and rolling mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention.

[0026] Figure 6 An axonometric view of the conveying mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention is shown.

[0027] Figure 7 An axonometric view of the lifting foot mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention is shown.

[0028] Figure 8 An axonometric view of the horizontal loading mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention is shown.

[0029] Figure 9 An axonometric view of the vertical loading mechanism of a coarse-grained soil direct shear and repeated shear test apparatus provided in an exemplary embodiment of the present invention is shown.

[0030] In the picture: 1. Shear box mechanism; 2. Friction detection and rolling mechanism; 3. Conveying mechanism; 4. Lifting foot mechanism; 5. Fixed floor; 6. Horizontal loading mechanism; 7. Vertical loading mechanism; 101. Upper shear box; 102. Upper wear-resistant plate; 103. Lifting ring; 104. Stacking plate; 105. Pad plate; 106. Pad block; 107. Mesh knob; 108. Gap insert plate; 109. Fixing plate; 110. Lower base plate; 111. Adjusting threaded block; 112. Adjusting screw; 113. Guide seat; 114. Rotating plunger; 115. Sliding seat; 116. Sliding shaft; 117. Lower shear box; 118. Lower wear-resistant plate; 119. Fork pin seat; 120. Lower base plate wear-resistant plate; 121. Reinforcing tube; 122. Enclosure; 123. Sealing gasket; 124. Angle iron support; 125. Backing; 126. Guide block; 127. Upper fitting guide rail; 128. Overflow outlet; 201. Guide fixing block; 202. Upper mounting plate; 203. Lower fitting guide rail; 204. Sealing plate; 205. Sealing plate rubber gasket; 206. Cloth cover pressure plate; 207. Dustproof cloth cover; 208. Lower mounting plate; 209. Friction mounting seat; 210. Friction sensor; 211. V-bearing seat; 212. V-bearing shaft; 213. V-bearing; 214. Locking round nut; 215. Roller bearing; 216. Roller seat; 217. Adjusting seat; 218. Friction bearing seat; 219. Oil nozzle; 220. Friction bearing shaft; 221. Friction bearing; 222. Friction roller conveyor; 223. Magnetic head mounting plate; 224. Magnetic head; 225. Chain pull seat; 226. Anti-collision sensing block; 227. Proximity sensing plate; 301. Idler shaft; 302. Idler lock plate; 303. Gearless idler wheel; 304. Conveyor pipe; 305. Chain; 306. Fixed angle iron; 307. Chain guide rail; 308. Top block; 309. Slide rail; 310. Idler wheel; 311. Bearing housing mounting plate; 312. Bearing housing; 313. End cap; 314. Metal sensor; 315. Proximity fixing sheet metal; 316. Cover; 317. Anti-collision block; 318. Fixed bracket; 319. Spacer; 320. Drive sprocket; 321. Drive shaft; 322. Motor mounting plate; 323. Motor; 324. Reinforcing rib plate; 41. Shock-absorbing and fixed chassis; 42. Locking ring; 43. Lifting shaft; 44. Leveling block; 45. Fixing screw; 46. Large shim; 61. Horizontal servo motor; 62. Push plate; 63. Load mounting plate; 64. Horizontal pressure sensor; 65. Locking sleeve; 66. Pin hole end; 67. Connector; 68. Push plate fixing seat; 701. Vertical servo motor; 702. Vertical displacement sensor; 703. Crossbeam; 704. Vertical displacement sensor mounting plate; 705. Fixed load upper plate; 706. Vertical pressure sensor; 707. Fixed load lower plate; 708. Pressure transmission plate; 709. Pressure transmission wear-resistant plate; 710. Support beam; 711. Pin; 712. Pin seat; 713. Vertical base; 714. Magnetic track; 715. Horizontal displacement sensor; 716. V-shaped interlocking guide rail; 717. Column. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0032] In this specification, identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings, while the terms "bottom surface," "top surface," "inner," and "outer" refer to directions towards or away from a specific component. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this specification, "multiple" means two or more.

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Figure 1 This diagram shows an overall axonometric view of a coarse-grained soil direct shear and repeated shear testing apparatus according to an exemplary embodiment of the present invention. The apparatus includes a shear box mechanism 1, comprising a lower base plate 110, a lower shear box 117 mounted on the lower base plate 110, and an upper shear box 101 mounted on the lower shear box 117. The apparatus is used to contain coarse-grained samples, and the shearing operation is achieved through the relative movement of the lower shear box 117 and the upper shear box 101 (see reference...). Figure 2 , Figure 3The friction detection and rolling mechanism 2 includes an upper mounting plate 202 and a lower mounting plate 208. The upper mounting plate 202 is connected to the guide block 126 and the upper fitting guide rail 127 at the bottom of the shear box mechanism 1 via a guide fixing block 201 and a lower fitting guide rail 203, respectively. A dustproof cloth cover 207 is installed between the upper mounting plate 202 and the lower mounting plate 208 via a cloth cover pressure plate 206. A friction sensor 210 is also provided between the upper mounting plate 202 and the lower mounting plate 208 (see reference). Figure 4 , Figure 5 ); conveying mechanism 3, which is connected to the chain pull seat 225 of friction detection and rolling mechanism 2 via chain 305, is used to drive friction detection and rolling mechanism 2 to move along slide 309 (see reference). Figure 6 ); and a horizontal loading mechanism 6 and a vertical loading mechanism 7, wherein the horizontal loading mechanism 6 is mounted on one side of the vertical loading mechanism 7 (see also...). Figure 8 , Figure 9 The horizontal loading mechanism 6 is used to apply horizontal shearing force to the lower shear box 117 and cooperates with the sensor to detect the horizontal force and displacement; the vertical loading mechanism 7 is used to apply vertical pressure to the coarse particle sample in the shear box mechanism 1 and cooperates with the sensor to detect the vertical displacement and pressure, thereby carrying out the consolidation process of the sample.

[0035] In this embodiment, the lower base plate 110, lower shear box 117, and upper shear box 101 of the shear box mechanism 1 accommodate coarse particle samples, and shearing is achieved through relative motion. The upper mounting plate 202 of the friction detection and rolling mechanism 2 is fitted with the shear box mechanism 1, the dust cover 207 is dustproof, and the friction sensor 210 can work with the horizontal servo motor 61 to detect the friction force during the shearing process. The conveying mechanism 3 is connected to the chain pull seat 225 through the chain 305, driving the friction detection and rolling mechanism 2 to move along the slide 309. The horizontal loading mechanism 6 applies a horizontal shearing force, and works with the sensor to detect the horizontal force and displacement; the vertical loading mechanism 7 applies a vertical pressure, and works with the sensor to detect the vertical displacement and pressure.

[0036] For details, please refer to Figure 2 and Figure 3The shear box mechanism 1 further includes: an upper wear-resistant plate 102 installed inside the upper shear box 101; a sliding seat 115 installed outside the upper shear box 101; a sliding shaft 116 passing through a vertical shaft hole in the sliding seat 115; a rotating plunger 114 passing through a transverse shaft hole in the sliding seat 115; a lower wear-resistant plate 118 installed inside the lower shear box 117; a guide seat 113 installed outside the lower shear box 117; a lower bottom plate wear-resistant plate 120 installed on the lower bottom plate 110; a retaining wall 122 installed around the lower bottom plate 110; a flexible conduit 121 elastically disposed inside the shear box mechanism 1; and a sealing gasket installed between the retaining wall 122 and the lower bottom plate 110. 123, a support 125 installed on one side of the guide block 126, angle irons 124 installed on both sides of the bottom of the lower base plate 110, and an overflow port 128 located at the bottom of the lower base plate 110 and connected to the inner side of the shear box mechanism 1; wherein, the rotating plunger 114 is used to fix the position of the sliding shaft 116 in the sliding seat 115, the guide seat 113 corresponds to the position of the sliding seat 115, the bottom end of the sliding shaft 116 is inserted into the guide seat 113, the bottom of the reinforcing tube 121 is tightly fitted to the outer periphery of the lower base plate 110, and the top of the reinforcing tube 121 is flipped over the upper shear box 101 and tightly fitted to the top outer periphery of the upper shear box 101 through the flange.

[0037] In this embodiment, the upper wear-resistant plate 102 and the lower wear-resistant plate 118 are used to reduce wear during shearing; the sliding seat 115, the sliding shaft 116 cooperate with the guide seat 113 to assist the relative movement of the upper and lower shear boxes, and the rotating plunger 114 is used to fix the position of the sliding shaft 116. The lower base plate wear-resistant plate 120 is used to protect the lower base plate 110; the enclosure 122 and the sealing gasket 123 are used to prevent the sample from overflowing; the reinforcing tube 121 is used to seal the shearing space; the support 125 is used to stabilize the guide block 126; the support angle iron 124 is used to raise the mechanism to prevent wear; and the overflow port 128 is used for drainage.

[0038] Further, see Figure 2 and Figure 3 A stacking plate 104, a pad 105, and a gap insert 108 are provided between the upper shear box 101 and the lower shear box 117. The upper and lower parts of the gap insert 108 are threadedly connected to the upper shear box 101 and the lower shear box 117 respectively through a mesh knob 107 and a pad 106. A fixing plate 109 is installed at the right angle between the lower shear box 117 and the lower base plate 110. An adjusting threaded block 111 is installed on the side of the fixing plate 109 away from the lower shear box 117. An adjusting screw 112 passes through the adjusting threaded block 111 and abuts against the fixing plate 109. A fork pin seat 119 is also installed on one side of the lower shear box 117. Lifting rings 103 are also installed on the lower base plate 110 near the four corners.

[0039] In this embodiment, the stacking plate 104 and pad 105 between the upper shear box 101 and the lower shear box 117 have an adjustable gap. The gap insert plate 108, in conjunction with the textured knob 107 and the pad block 106, can fix the relative positions of the two. The fixing plate 109, adjusting threaded block 111, and adjusting screw 112 between the lower shear box 117 and the lower base plate 110 can fix and finely adjust the position of the lower shear box; the fork pin seat 119 is used to connect the loading mechanism; the lifting ring 103 facilitates hoisting.

[0040] Specifically, see Figure 4 and Figure 5 The friction detection and rolling mechanism 2 further includes: a friction roller conveyor 222 mounted on the upper mounting plate 202; two friction mounting seats 209 respectively mounted on the opposing surfaces of the upper mounting plate 202 and the lower mounting plate 208; a friction sensor 210 mounted between the two friction mounting seats 209; a friction bearing seat 218 mounted on the lower mounting plate 208; a friction bearing shaft 220 passing through the bearing hole of the friction bearing seat 218; a friction bearing 221 mounted on the front end of the friction bearing shaft 220; an oil nozzle 219 mounted on the end of the friction bearing shaft 220 and connected to the internal oil passage of the friction bearing shaft 220; an adjusting seat 217 mounted on the upper mounting plate 202 and located on one side of the friction bearing seat 218; and a roller seat 216 mounted on the lower mounting plate 208. The components include: a roller bearing 215 installed in the bearing hole of the roller seat 216; a magnetic head mounting plate 223 installed at the bottom of the lower mounting plate 208; a magnetic head 224 installed on the magnetic head mounting plate 223; a V-bearing seat 211 installed on the lower mounting plate 208; a V-bearing shaft 212 installed in the shaft hole of the V-bearing seat 211; a V-bearing 213 fixed to the shaft end of the V-bearing shaft 212 by a locking nut 214; and an anti-collision sensing block 226 and a proximity sensing plate 227 installed at the bottom of the lower mounting plate 208. The friction sensor 210 is protected from dust contamination by a sealing plate rubber gasket 205 and a sealing plate 204. The adjusting seat 217 can slide the friction bearing seat 218, causing the sidewall of the friction bearing 221 to be constrained from moving against the friction roller conveyor 222.

[0041] In this embodiment, the friction sensor 210 between the friction mounting bases 209 can work with the horizontal servo motor 61 to detect the friction force during the shearing process. The sealing plate 204 and the sealing plate rubber gasket 205 are used for sealing protection. The friction bearing housing 218, the friction bearing shaft 220, and the friction bearing 221 cooperate with each other. The oil nozzle 219 is used for oil lubrication. The adjusting seat 217 can make the friction bearing 221 contact the friction roller conveyor 222. The roller seat 216 and the roller bearing 215 assist the movement of the mechanism. The magnetic head 224 on the magnetic head mounting plate 223 assists in detection. The V-bearing housing 211, the V-bearing shaft 212, and the V-bearing 213 are fixed by the locking round nut 214 and play a guiding role. The anti-collision sensing block 226 and the proximity sensing plate 227 are used for positioning protection.

[0042] For more details, please refer to Figure 6 The conveying mechanism 3 includes: a conveying pipe 304 mounted on a fixed bracket 318 via a fixed angle iron 306; a chain guide rail 307 mounted on the conveying pipe 304 for guiding the chain 305; an idler shaft 301 mounted on one end and the middle of the conveying pipe 304 via an idler lock plate 302; a toothless idler 303 sleeved on the idler shaft 301 and meshing with the chain 305; a motor mounting plate 322 mounted on the conveying pipe 304; a motor 323 mounted on the motor mounting plate 322; a bearing housing mounting plate 311 connected to the motor mounting plate 322 via a reinforcing rib plate 324; and a bearing housing mounted on the bearing housing mounting plate 311. 312, an end cap 313 installed on the outside of the bearing housing 312, a spacer 319 and a drive sprocket 320 located on the side of the bearing housing mounting plate 311 away from the bearing housing 312, an idler wheel 310 installed at the other end of the conveying pipe 304, and a drive shaft 321 sequentially passing through the drive sprocket 320, the spacer 319 and the bearing housing 312; wherein, a top block 308 is installed below the idler wheel shaft 301 located in the middle of the conveying pipe 304 to support the idler wheel shaft 301, so that the toothless idler wheel 303 supports the chain 305 away from the conveying pipe 304; the idler wheel 310 and the drive sprocket 320 mesh with the chain 305, and the toothless idler wheel 303 directly contacts the chain 305.

[0043] In this embodiment, the conveying pipe 304 is fixed to the fixed bracket 318 by a fixed angle iron 306, and the chain guide rail 307 guides the chain 305; the idler shaft 301 is used to mount the toothless idler 303 to assist the chain 305 in transmission, and the top block 308 under the middle idler shaft 301 supports it so that the chain is away from the conveying pipe 304. The motor 323 is fixed by the motor mounting plate 322, and drives the drive sprocket 320 through the drive shaft 321, which cooperates with the idler 310 to drive the chain 305; the bearing seat 312 and other components support the drive shaft, and the reinforcing ribs 324 enhance the structural stability.

[0044] Further, please refer to Figure 6The conveying pipe 304 is also equipped with a proximity fixing sheet metal 315, and a metal sensor 314 corresponding to the proximity sensing plate 227 of the friction detection and rolling mechanism 2 is installed on the proximity fixing sheet metal 315; the conveying pipe 304 is also equipped with a cover 316 that covers the chain 305, the drive sprocket 320 and the toothless idler wheel 303; the slide 309 is installed on the fixed bracket 318, and an anti-collision block 317 corresponding to the anti-collision sensing block 226 of the friction detection and rolling mechanism 2 is installed on the slide 309.

[0045] In this embodiment, a metal sensor 314 is installed on the proximity fixing sheet metal 315 on the conveying pipe 304, corresponding to the proximity sensing plate 227 of the friction detection and rolling mechanism 2, which can accurately detect its position and ensure accurate movement positioning. The cover 316 encloses the chain 305, the drive sprocket 320, and the toothless idler wheel 303, preventing personnel from touching the moving parts and foreign objects from being drawn in, thus providing safety protection. The slide rail 309 on the fixed bracket 318 is equipped with anti-collision blocks 317, corresponding to the anti-collision sensing blocks 226 of the friction detection and rolling mechanism 2, which can prevent equipment damage caused by excessive movement and ensure operational safety. These components further improve the safety and reliability of the conveying mechanism.

[0046] Specifically, please refer to Figure 8 The horizontal loading mechanism 6 includes: a push plate 62 mounted on a push plate fixing seat 68, a horizontal servo motor 61 mounted on the push plate 62, a load mounting plate 63 mounted on the output end of the horizontal servo motor 61, a horizontal pressure sensor 64 mounted on the load mounting plate 63, a pin hole end 66 mounted on the horizontal pressure sensor 64 via a locking sleeve 65, and a connector 67 mounted on the push plate fixing seat 68 and connected to the vertical base 713 of the vertical loading mechanism 7; wherein, the pin 711 of the vertical loading mechanism 7 is inserted into the pin hole end 66 and the fork pin seat 119 of the shear box mechanism 1 to realize the consolidation and shear test of the soil sample.

[0047] In this embodiment, the push plate 62 on the push plate fixing seat 68 is used to mount the horizontal servo motor 61. The horizontal servo motor 61 is connected to the horizontal pressure sensor 64 through the load mounting plate 63 to provide power for shearing. The horizontal pressure sensor 64 is fitted with a locking sleeve 65 to the pin hole end 66. The pin 711 of the vertical loading mechanism 7 is inserted into the pin hole end 66 and the fork pin seat 119 of the shear box mechanism 1 to achieve the connection and coordination of the three. The connecting piece 67 connects the push plate fixing seat 68 and the vertical base 713 to ensure overall stability and coordinate the recording of horizontal shearing force and shearing displacement.

[0048] For details, please refer to Figure 9The vertical loading mechanism 7 includes: a pin seat 712 mounted on the vertical base 713; a pin 711 inserted into the pin hole of the pin seat 712; a horizontal displacement sensor 715 mounted on the vertical base 713; a V-shaped fitting guide rail 716 mounted on the vertical base 713 and corresponding to the V-shaped bearing 213 of the friction detection and rolling mechanism 2; a magnetic rail 714 mounted on the vertical base 713 and corresponding to the magnetic head 224 of the friction detection and rolling mechanism 2; columns 717 mounted on both sides of the vertical base 713; a support beam 710 mounted between the two columns 717; and a crossbeam 710 mounted on the top of the two columns 717. 03. A vertical displacement sensor 702 is mounted on the crossbeam 703 via a vertical displacement sensor mounting plate 704; a vertical servo motor 701 is mounted on the crossbeam 703; a fixed load upper plate 705 is mounted on the output end of the vertical servo motor 701; a fixed load lower plate 707 is connected to the fixed load upper plate 705 via a vertical pressure sensor 706; and a pressure transmission plate 708 is mounted on the bottom of the fixed load lower plate 707. The pressure transmission plate 708 is also equipped with a pressure transmission wear-resistant plate 709 at its bottom, which is used to uniformly transmit the pressure applied by the vertical servo motor 701 to the coarse particle sample, while reducing the wear of the pressure transmission plate 708.

[0049] In this embodiment, the pin seat 712 on the vertical base 713 is fitted with a pin 711, connecting the horizontal loading mechanism 6 and the shear box mechanism 1; the horizontal displacement sensor 715 measures the displacement, the V-shaped fitting guide rail 716 cooperates with the V-shaped bearing 213 for guidance, and the magnetic rail 714 corresponds to the magnetic head 224 for auxiliary positioning. The vertical servo motor 701 on the crossbeam 703 transmits pressure through the fixed load plate 705, and the pressure-transmitting wear-resistant plate 709 applies the fixed pressure. The vertical displacement sensor and the vertical pressure sensor work together to realize vertical loading, pressure transmission and data detection, ensuring the accuracy of the test.

[0050] For more details, please refer to Figure 7 The coarse-grained soil direct shear and repeated shear test equipment also includes: a lifting foot mechanism 4, which includes a shock-absorbing fixed base 41, a lifting shaft 43 installed on the shock-absorbing fixed base 41, a leveling block 44 threaded on the lifting shaft 43, a locking ring 42 threaded on the lifting shaft 43 and abutting against the leveling block 44, and a fixing screw 45 installed on the top of the lifting shaft 43 through a large washer 46; wherein, the bottom of the horizontal loading mechanism 6 and the vertical loading mechanism 7 are both equipped with the lifting foot mechanism 4, and the fixing screw 45 is respectively connected to the push plate fixing seat 68 of the horizontal loading mechanism 6 and the vertical base 713 of the vertical loading mechanism 7; the shock-absorbing fixed base 41 of the lifting foot mechanism 4 is installed on the fixed floor 5, which reduces the installation difficulty.

[0051] In this embodiment, the shock-absorbing and fixed chassis 41 is installed on the fixed floor 5, serving a shock-absorbing and stabilizing function. The leveling block 44 on the lifting shaft 43 is height-adjustable and, in conjunction with the locking ring 42, is fixed in position, achieving leveling of the horizontal loading mechanism 6 and the vertical loading mechanism 7. The fixing screw 45 connects the push plate fixing seat 68 and the vertical base 713 through the large washer 46, stably fixing the horizontal and vertical loading mechanisms. It provides support for the two mechanisms, ensuring the stability of the equipment during loading, reducing the impact of vibration, ensuring accurate force transmission during the test, and improving the stability of equipment operation and the accuracy of the test.

[0052] Next, the test methods of the coarse-grained soil direct shear and repeated shear test equipment involved in the embodiments of the present invention will be described.

[0053] Step S1, Lower shear box installation: Tightly tighten the reinforcing tube 121 onto the lower base plate 110, place the wear-resistant plate 120 of the lower base plate inside the reinforcing tube 121 and ensure it fits snugly against the lower base plate 110; fix the lower wear-resistant plate 118 onto the lower shear box 117, hoist the lower shear box 117 onto the lower base plate 110, fix the adjusting threaded block 111 onto the lower base plate 110, adjust the adjusting screw 112 on the adjusting threaded block 111 to precisely align the lower shear box 117 to the reference position, and then firmly fix the lower shear box 117 onto the lower base plate 110 using the fixing plate 109; to prevent coarse particle samples from overflowing from the side during the consolidation test, install a barrier 122 and a sealing gasket 123 on the lower base plate 110, and install an overflow outlet 128 below it for consolidation drainage.

[0054] Step S2, Upper Shear Box Installation: Select a pad 105 of the appropriate height according to the sample requirements and fix it on the lower shear box 117. Then assemble the stacked plate 104 to the same height as the pad 105. Fix the upper wear-resistant plate 102 and the sliding seat 115 on the upper shear box 101. Rotate the rotary plunger 114 to slide the sliding shaft 116 to the lowest position and then rotate the rotary plunger 114 again to lock it. When hoisting the upper shear box 101, align the sliding shaft 116 with the guide seat 113 fixed on the lower shear box 117. Turn the reinforcing tube 121 over the upper shear box 101, insert the gap insert 108 between the upper and lower shear boxes, add the shim 106, and then rotate the mesh knob 107 to tighten it. Fix the lifting ring 103 on the lower base plate 110 for easy adjustment and transportation later.

[0055] Step S3, Placement and Fixing of Shear Box Mechanism: Place the shear box mechanism 1 in the coarse particle sample filling area to fill the coarse particle sample. Since the upper fitting guide rail 127 and guide block 126 are covered with lubricating oil, in order to avoid them directly contacting the ground and causing wear and dirt, the shear box mechanism 1 is raised by installing support angle iron 124 at the bottom; the backrest 125 is fixedly installed on the lower base plate 110, and the guide block 126 is pressed to enhance the stability during use; after the coarse particle sample is filled, the reinforcing tube 121 is tied at the wear-resistant plate 120 of the upper lower base plate, and the shear box mechanism 1 is hoisted onto the friction detection and rolling mechanism 2.

[0056] Step S4: Connecting and fixing the friction detection and rolling mechanism with the shear box mechanism: Engage the guide fixing block 201 and the lower fitting guide rail 203 with the guide block 126 and the upper fitting guide rail 127 on the shear box mechanism 1, respectively, and tighten the bolts on the guide fixing block 201 to fix the shear box mechanism 1 relative to the friction detection and rolling mechanism 2. To obtain the friction force generated during the shearing process, install a friction sensor 210 between the friction mounting base 209 of the upper mounting plate 202 and the lower mounting plate 208. After installation... The sealing plate 204 and sealing plate rubber gasket 205 are fixedly installed on the upper mounting plate 202 to enclose the operating space; to provide support during the consolidation process, a friction roller conveyor 222 is fixedly installed on the upper mounting plate 202, and a tensioning seat 217 and a friction bearing seat 218 are fixedly installed on the lower mounting plate 208. A friction bearing shaft 220 is fixedly installed inside the friction bearing seat 218, and a friction bearing 221 is fixed at its front end; to reduce the coefficient of friction, an oil nozzle 219 is installed on the friction bearing shaft 220, and the tensioning seat 217 is adjusted by... The bolts on plate 7 allow the friction bearing housing 218 to slide and the friction bearing 221 to contact the friction roller conveyor 222. To reduce environmental impact, a cloth cover pressure plate 206 and a dustproof cloth cover 207 are installed between the upper mounting plate 202 and the lower mounting plate 208 to isolate dust. A roller seat 216 and a roller bearing 215 are installed on the lower mounting plate 208 to facilitate friction detection and relative rolling of the rolling mechanism 2 on the conveying mechanism 3. The chain pull seat 225 is fixedly installed on the lower mounting plate 208 and connected to the chain 305 to lift... Provides horizontal traction force; to detect horizontal relative displacement, the magnetic head mounting plate 223, the anti-collision sensing block 226, and the proximity sensing plate 227 are fixed relative to each other on the lower mounting plate 208, and the magnetic head 224 is fixed on the magnetic head mounting plate 223 to obtain high-precision displacement data; the V-bearing seat 211 is fixed on the lower mounting plate 208, and the V-bearing shaft 212 is fixedly mounted on the V-bearing seat 211. The V-bearing 213 is fixed relative to the V-bearing shaft 212 by locking round nut 214 to provide guidance for shearing.

[0057] Step S5, Conveying Mechanism Operation and Positioning: Operate the conveying mechanism 3 to move the friction detection and rolling mechanism 2 to the shear box mechanism 1 to the loading area. The chain pull seat 225 is connected to the chain 305, and the chain 305 rolls relative to each other on the chain guide rail 307. The chain guide rail 307 is fixedly installed on the conveying pipe 304. The idler wheel lock plate 302 is fixedly installed on the conveying pipe 304 to lock the idler wheel shaft 301 and the relatively rolling toothless idler wheel 303. The toothless idler wheel 303 assists the chain 305 in rolling. Because the chain 305 is relatively long, it may rub against the conveying pipe 304 during movement. A top block 308 is provided in the middle of the conveying pipe 304. The top block 308 can make the idler wheel shaft 301 move upward, driving the toothless idler wheel 303 to lift the chain 305 away from the conveying pipe 304. The power of the chain 305 comes from the motor 323, which is fixed on the motor mounting plate 322. The motor mounting plate 322 is connected to the bearing seat mounting plate 311. The chain 305 is fixed to the conveying pipe 304 via reinforcing ribs 324. The tension of the chain 305 can be adjusted by bolts on the conveying pipe 304. The drive sprocket 320 and idler sprocket 310 are in direct contact with the chain 305. The drive shaft 321 passes through the bearing housing 312, the drive sprocket 320, and the spacer 319, and is fixed to the chain 305 via end caps 313. The proximity fixing sheet metal 315 is fixed to the conveying pipe 304, and the metal sensor 314 is fixed to the proximity fixing sheet metal 315 to detect whether the proximity sensing plate 227 has reached the corresponding position. The cover 316 provides protection for the running chain 305 to prevent personnel limbs and foreign objects from being caught in it. The roller bearing 215 rolls relative to the slide rail 309. The anti-collision block 317 on the slide rail 309 can prevent damage to the equipment due to exceeding the limit. The slide rail 309 and the conveying pipe 304 are fixed to the fixed bracket 318 by fixing angle iron 306, and the overall height can be adjusted according to the site requirements.

[0058] Step S6, Loading Mechanism Installation and Leveling: Install the lifting foot mechanism 4 below the horizontal loading mechanism 6 and the vertical loading mechanism 7. The shock-absorbing fixed chassis 41 contacts the fixed floor 5. Leveling is achieved by adjusting the lifting shaft 43 to control the lifting block 44. The locking ring 42 is tightened to fix the relative position of the lifting shaft 43. The fixing screw 45 is fixed on the lifting shaft 43. To reduce friction, a large shim 46 is placed in the middle, and the fixing is strengthened by the nut and washer. The horizontal loading mechanism 6 is fixed on the fixed floor 5 by the fixing screw 45. The fixing screw 45 passes through the push plate fixing seat 68 and is fixed by the nut and washer. The push plate 62 is fixed on the push plate fixing seat 68. The horizontal servo motor 61 is fixed on the push plate 62. The load mounting plate 63 is fixed on the output end of the horizontal servo motor 61. One end of the horizontal pressure sensor 64 is connected to the load mounting plate 63, and the other end is fixed to the mounting pin hole end 66 by the locking sleeve 65. One end of the connector 67 is fixed on the push plate fixing seat 68, and the other end is connected to the vertical loading mechanism 7.

[0059] Step S7, Consolidation Test Operation: The other end of the connector 67 is fixed to the vertical base 713, the pin seat 712 is fixed to the vertical base 713, the pin 711 is inserted into the pin hole of the pin seat 712, the V-shaped fitting guide rail 716, the horizontal displacement sensor 715, the magnetic rail 714 and the column 717 are all fixed to the vertical base 713; the conveying mechanism 3 drives the shear box mechanism 1 on the friction detection and rolling mechanism 2 into the interior of the vertical loading mechanism 7, and the roller bearing 215 disengages from the slide rail 3. 09. The V-bearing 213 and the V-shaped mating guide rail 716 begin to roll. The anti-collision sensing block 226 contacts the horizontal displacement sensor 715 to generate horizontal displacement data. The magnetic head 224 contacts the magnetic rail 714 to generate horizontal displacement data. Based on the reference horizontal displacement data, the shear box mechanism 1 is transported to the designated position. The conveying mechanism 3 stops transporting and switches to the consolidation test loading mode. The pin 711 is inserted between the pin hole end 66 and the fork pin seat 119. The support beam 710 is fixed to the two columns 717. Between them, the upper shear box 101 contacts and is relatively fixed to the support beam 710; the upper end of the column 717 is fixed to the crossbeam 703, and the crossbeam 703 is fixed to the vertical servo motor 701 and the vertical displacement sensor mounting plate 704. The vertical displacement sensor 702 is fixed to the vertical displacement sensor mounting plate 704. The upper plate of the consolidation load 705 is fixed to the output end of the vertical servo motor 701. The vertical pressure sensor 706 is installed between the upper plate of the consolidation load 705 and the lower plate of the consolidation load 707. The lower plate of the consolidation load 707 is relatively fixed to the pressure transmission plate 708. The pressure transmission wear-resistant plate 709 is fixed to the pressure transmission plate 708. The vertical servo motor 701 drives the pressure transmission plate 708 to apply the specified consolidation pressure. The vertical pressure sensor 706 outputs the vertical pressure value, and the vertical displacement sensor 702 outputs the vertical displacement. When the pressure value output by the vertical pressure sensor 706 is stably maintained at the specified consolidation pressure, and the vertical displacement output by the vertical displacement sensor 702 no longer changes within a certain period of time, the consolidation ends.

[0060] Step S8, Shearing Test Operation: The operator loosens the mesh knob 107 on the shear box mechanism 1, causing the pad 106 to fall off, removes the gap insert plate 108, rotates the rotating plunger 114 to pull the sliding shaft 116 to the upper position, and locks the rotating plunger 114 to disengage the sliding shaft 116 from the lower shear box 117; the horizontal servo motor 61 pushes the horizontal pressure sensor 64 forward, the horizontal pressure sensor 64 pushes the pin hole end 66, the pin hole end 66 pushes the fork pin seat 119, the fork pin seat 119 pushes the lower shear box 117, and the lower shear... Box 117 drives the upper mounting plate 202. The frictional force generated between the upper mounting plate 202 and the lower mounting plate 208 is jointly output by the friction sensor 210 and the horizontal servo motor 61. When the measured horizontal displacement reaches the threshold or the sample is sheared, the mechanism stops, the pin 711 is pulled out, and the conveying mechanism 3 is moved. After the proximity sensor plate 227 approaches the metal sensor 314, the conveying mechanism 3 stops moving, the bolts on the guide fixing block 201 are loosened, and the shearing box mechanism 1 is lifted to the cleaning area by the lifting ring 103. After cleaning, it is stored. It can be understood that the test operation of reciprocating shearing is to repeat the direct shearing operation.

[0061] In the embodiments disclosed in this invention, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments disclosed in this invention according to the specific circumstances.

[0062] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A device for direct shearing and repeated shearing tests on coarse-grained soil, characterized in that, include: The shearing box mechanism (1) includes a lower base plate (110), a lower shearing box (117) mounted on the lower base plate (110), and an upper shearing box (101) mounted on the lower shearing box (117). It is used to hold coarse particle samples and to perform shearing operations through the relative movement of the lower shearing box (117) and the upper shearing box (101). Friction detection and rolling mechanism (2) includes an upper mounting plate (202) and a lower mounting plate (208). The upper mounting plate (202) is connected to the guide block (126) at the bottom of the shear box mechanism (1) and the upper mounting rail (127) respectively through the guide fixing block (201) and the lower fitting guide rail (203). A dustproof cloth cover (207) is installed between the upper mounting plate (202) and the lower mounting plate (208) through the cloth cover pressure plate (206). A friction sensor (210) is also provided between the upper mounting plate (202) and the lower mounting plate (208). A conveying mechanism (3), which is connected to the chain pull seat (225) of the friction detection and rolling mechanism (2) via a chain (305), is used to drive the friction detection and rolling mechanism (2) to move along the slide (309); and A horizontal loading mechanism (6) and a vertical loading mechanism (7), wherein the horizontal loading mechanism (6) is mounted on one side of the vertical loading mechanism (7); The horizontal loading mechanism (6) is used to apply a horizontal shearing force to the lower shear box (117) and cooperate with the sensor to detect the horizontal force and displacement; the vertical loading mechanism (7) is used to apply a vertical pressure to the coarse particle sample in the shear box mechanism (1) and cooperate with the sensor to detect the vertical displacement and pressure.

2. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 1, characterized in that, The shear box mechanism (1) further includes: The upper wear-resistant plate (102) installed inside the upper shear box (101), the sliding seat (115) installed outside the upper shear box (101), the sliding shaft (116) passing through the vertical shaft hole of the sliding seat (115), the rotating plunger (114) passing through the transverse shaft hole of the sliding seat (115), the lower wear-resistant plate (118) installed inside the lower shear box (117), the guide seat (113) installed outside the lower shear box (117), and the lower bottom plate wear-resistant plate (118) installed on the lower bottom plate (110) 20) A fence (122) installed around the lower base plate (110), a reinforcing tube (121) elastically set inside the shear box mechanism (1), a sealing gasket (123) installed between the fence (122) and the lower base plate (110), a backing (125) installed on one side of the guide block (126), angle irons (124) installed on both sides of the bottom of the lower base plate (110), and an overflow outlet (128) set at the bottom of the lower base plate (110) and connected to the inside of the shear box mechanism (1). The rotating plunger (114) is used to fix the position of the sliding shaft (116) in the sliding seat (115). The guide seat (113) corresponds to the position of the sliding seat (115). The bottom end of the sliding shaft (116) is inserted into the guide seat (113). The bottom of the tendon tube (121) is tightly fitted on the outer periphery of the lower base plate (110). The top of the tendon tube (121) is flipped over the upper shear box (101) and tightly fitted on the top outer periphery of the upper shear box (101) through the flange.

3. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 2, characterized in that: A stacking plate (104), a pad plate (105), and a gap insert plate (108) are provided between the upper shear box (101) and the lower shear box (117). The upper and lower parts of the gap insert plate (108) are threadedly connected to the upper shear box (101) and the lower shear box (117) respectively through a mesh knob (107) and a pad block (106). A fixing plate (109) is installed at the right angle between the lower shear box (117) and the lower base plate (110). An adjusting thread block (111) is installed on the side of the fixing plate (109) away from the lower shear box (117). An adjusting screw (112) passes through the adjusting thread block (111) and abuts against the fixing plate (109). A fork pin seat (119) is also installed on one side of the lower shear box (117). Lifting rings (103) are also installed on the lower base plate (110) near the four corners.

4. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 1, characterized in that, The friction detection and rolling mechanism (2) also includes: The following components are mounted on the upper mounting plate (202): a friction roller conveyor (222), two friction mounting seats (209) respectively mounted on the opposite surfaces of the upper mounting plate (202) and the lower mounting plate (208), a friction sensor (210) mounted between the two friction mounting seats (209), a friction bearing seat (218) mounted on the lower mounting plate (208), a friction bearing shaft (220) passing through the bearing hole of the friction bearing seat (218), a friction bearing (221) mounted on the front end of the friction bearing shaft (220), an oil nozzle (219) mounted on the end of the friction bearing shaft (220) and connected to the internal oil passage of the friction bearing shaft (220), and a friction sensor (210) mounted on the upper mounting plate (202) and located on the friction roller conveyor (222). The bearing housing (218) includes a tensioning seat (217) on one side, a roller seat (216) mounted on the lower mounting plate (208), a roller bearing (215) mounted in the bearing hole of the roller seat (216), a magnetic head mounting plate (223) mounted on the bottom of the lower mounting plate (208), a magnetic head (224) mounted on the magnetic head mounting plate (223), a V-shaped bearing housing (211) mounted on the lower mounting plate (208), a V-shaped bearing shaft (212) mounted in the shaft hole of the V-shaped bearing housing (211), a V-shaped bearing (213) fixed to the shaft end of the V-shaped bearing shaft (212) by a locking round nut (214), and an anti-collision sensing block (226) and a proximity sensing plate (227) mounted on the bottom of the lower mounting plate (208). The position of the friction sensor (210) is protected from dust contamination by the sealing plate rubber gasket (205) and the sealing plate (204); the adjusting seat (217) can slide the friction bearing seat (218) so that the side wall of the friction bearing (221) is constrained to move with the friction roller track (222).

5. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 1, characterized in that, The conveying mechanism (3) includes: The following components are described: a conveying pipe (304) mounted on a fixed bracket (318) via a fixed angle iron (306); a chain guide rail (307) mounted on the conveying pipe (304) for guiding the chain (305); an idler shaft (301) mounted on one end and the middle of the conveying pipe (304) via an idler lock plate (302); a toothless idler wheel (303) sleeved on the idler shaft (301) and meshing with the chain (305); a motor mounting plate (322) mounted on the conveying pipe (304); and a motor (323) mounted on the motor mounting plate (322). The bearing housing mounting plate (311) is connected to the motor mounting plate (322) via the reinforcing rib plate (324), the bearing housing (312) is mounted on the bearing housing mounting plate (311), the end cap (313) is mounted on the outside of the bearing housing (312), the spacer (319) and the drive sprocket (320) are located on the side of the bearing housing mounting plate (311) away from the bearing housing (312), the idler wheel (310) is mounted on the other end of the conveying pipe (304), and the power shaft (321) is sequentially passed through the drive sprocket (320), the spacer (319) and the bearing housing (312). A top block (308) is installed below the idler shaft (301) in the middle of the conveying pipe (304) to support the idler shaft (301) so that the toothless idler (303) lifts the chain (305) away from the conveying pipe (304); the idler (310) and the drive sprocket (320) mesh with the chain (305), and the toothless idler (303) is in direct contact with the chain (305).

6. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 5, characterized in that: The conveying pipe (304) is also equipped with a proximity fixing sheet metal (315), and the proximity fixing sheet metal (315) is equipped with a metal sensor (314) corresponding to the proximity sensing plate (227) of the friction detection and rolling mechanism (2); the conveying pipe (304) is also equipped with a cover (316) that covers the chain (305), the drive sprocket (320) and the toothless idler wheel (303); the slide (309) is installed on the fixed bracket (318), and the slide (309) is equipped with an anti-collision block (317) corresponding to the anti-collision sensing block (226) of the friction detection and rolling mechanism (2).

7. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 1, characterized in that, The horizontal loading mechanism (6) includes: A push plate (62) mounted on a push plate mounting base (68), a horizontal servo motor (61) mounted on the push plate (62), a load mounting plate (63) mounted on the output end of the horizontal servo motor (61), a horizontal pressure sensor (64) mounted on the load mounting plate (63), a pin hole end (66) mounted on the horizontal pressure sensor (64) via a locking sleeve (65), and a connector (67) mounted on the push plate mounting base (68) and connected to the vertical base (713) of the vertical loading mechanism (7). The pin (711) of the vertical loading mechanism (7) is inserted into the pin hole end (66) and the fork pin seat (119) of the shear box mechanism (1) to realize the consolidation and shear test of the soil sample.

8. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 1, characterized in that, The vertical loading mechanism (7) includes: A pin seat (712) mounted on the vertical base (713), a pin (711) inserted into the pin hole of the pin seat (712), a horizontal displacement sensor (715) mounted on the vertical base (713), a V-shaped fitting guide rail (716) mounted on the vertical base (713) and corresponding to the V-shaped bearing (213) of the friction detection and rolling mechanism (2), a magnetic track (714) mounted on the vertical base (713) and corresponding to the magnetic head (224) of the friction detection and rolling mechanism (2), columns (717) mounted on both sides of the vertical base (713), and columns (717) mounted on the two columns. The support beam (710) between the columns (717), the crossbeam (703) installed on the top of the two columns (717), the vertical displacement sensor (702) installed on the crossbeam (703) via the vertical displacement sensor mounting plate (704), the vertical servo motor (701) installed on the crossbeam (703), the fixed load upper plate (705) installed on the output end of the vertical servo motor (701), the fixed load lower plate (707) connected to the fixed load upper plate (705) via the vertical pressure sensor (706), and the pressure transmission plate (708) installed at the bottom of the fixed load lower plate (707); The pressure transmission plate (708) is also equipped with a pressure transmission wear-resistant plate (709) at its bottom, which is used to uniformly transmit the pressure applied by the vertical servo motor (701) to the coarse particle sample, while reducing the wear of the pressure transmission plate (708).

9. The equipment for direct shearing and repeated shearing tests of coarse-grained soil according to claim 1, characterized in that, The equipment for direct shear and repeated shear tests of coarse-grained soil also includes: The lifting foot mechanism (4) includes a shock-absorbing fixed chassis (41), a lifting shaft (43) mounted on the shock-absorbing fixed chassis (41), a leveling block (44) threaded onto the lifting shaft (43), a locking ring (42) threaded onto the lifting shaft (43) and abutting against the leveling block (44), and a fixing screw (45) mounted on the top of the lifting shaft (43) via a large washer (46). The bottom of the horizontal loading mechanism (6) and the vertical loading mechanism (7) are both equipped with the lifting foot mechanism (4), and the fixed screw (45) is respectively connected to the push plate fixing seat (68) of the horizontal loading mechanism (6) and the vertical base (713) of the vertical loading mechanism (7); the shock-absorbing fixing chassis (41) of the lifting foot mechanism (4) is installed on the fixed floor (5).

10. A method for direct shear and repeated shear tests on coarse-grained soil, wherein the method is applied to the direct shear and repeated shear test equipment for coarse-grained soil as described in any one of claims 1 to 9, characterized in that, The method includes: S1. Consolidation test: The conveying mechanism (3) drives the shear box mechanism (1) into the vertical loading mechanism (7). The roller bearing (215) disengages from the slide (309), and the V-bearing (213) rolls along the V-shaped interlocking guide rail (716). The anti-collision sensing block (226) and the magnetic head (224) contact the horizontal displacement sensor (715) and the magnetic rail (714) respectively to measure the displacement. After reaching the position, the conveying mechanism (3) stops and keeps the sliding shaft (116) between the upper shear box (101) and the lower shear box (117) in the insertion state to prevent relative movement between the upper shear box (101) and the lower shear box (117) during the consolidation process. Switch to the consolidation mode. The vertical servo motor (701) drives the pressure plate (708) to apply the specified consolidation pressure. When the pressure value output by the vertical pressure sensor (706) is stably maintained at the specified consolidation pressure, and the vertical displacement output by the vertical displacement sensor (702) no longer changes within a certain period of time, the consolidation ends. S2. Shear test: Loosen the mesh knob (107) of the shear box mechanism (1) to make the pad (106) fall off, remove the gap insert (108), loosen the rotating plunger (114) to pull the sliding shaft (116) to the upper position and lock it, so that it is separated from the lower shear box (117); the horizontal servo motor (61) pushes the horizontal pressure sensor (64), which in turn drives the pin hole end (66), the fork pin seat (119) and the lower shear box (117) in sequence. The friction force generated by the upper mounting plate (202) and the lower mounting plate (208) is output by the friction sensor (210) and the horizontal servo motor (61); when the horizontal displacement reaches the threshold or the sample is sheared, stop, the pin (711) is pulled out, control the conveying mechanism (3) to make the proximity sensor plate (227) close to the metal sensor (314) and stop, loosen the guide fixing block (201) bolt, and use the lifting ring (103) to lift the shear box mechanism (1) to the cleaning area for cleaning and storage.

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