Rock-soil bearing capacity testing device

Abstract

The utility model discloses a rock-soil bearing capacity testing device, which belongs to the technical field of geological engineering and comprises a bottom plate, a support is fixedly mounted at the end of the upper wall of the bottom plate, power equipment is mounted on the upper wall of a transverse plate at the upper end of the support, and a buffer pressure head is fixedly mounted at the output end of the power equipment. A buffer pressure head is fixedly mounted on the upper wall of the bottom plate, a placing box corresponding to the buffer pressure head is fixedly mounted on the upper wall of the bottom plate, positioning assemblies are assembled on the upper wall of the bottom plate and located on the periphery of the placing box, and the output ends of the positioning assemblies penetrate through the placing box to act on the rock surface. Self-adaptive and high-stability lateral positioning of irregular rock samples is achieved, a safety pin triggering mechanism, a disc spring energy storage element and a hydraulic damping cavity are integrated in a buffering pressing head, and a multi-stage cooperative impact energy buffering mechanism is constructed.

Description

Technical Field

[0001] This utility model belongs to the field of geological engineering technology, and specifically provides a soil and rock bearing capacity testing device. Background Technology

[0002] In the field of geotechnical engineering, accurately determining the bearing capacity of rock and other soil materials is a crucial step in foundation design, slope stability assessment, and underground engineering construction. Existing geotechnical bearing capacity testing devices typically use a rigid indenter to apply vertical pressure to a rock sample placed on a pressure platform until the sample fails, thereby obtaining its ultimate bearing capacity.

[0003] However, such traditional devices have significant drawbacks: First, for irregularly shaped rock samples, conventional lateral restraints or clamping devices struggle to achieve effective and uniform fixation, leading to sample slippage or deflection during testing. This causes eccentricity in the applied load, severely impacting the accuracy and reliability of the test data. Second, rock materials, especially brittle rocks, undergo sudden brittle fracture upon reaching their ultimate bearing capacity, releasing enormous impact energy instantaneously. This impact force can damage precision components such as pressure sensors and drive devices. Therefore, a soil and rock bearing capacity testing device needs to be designed. Utility Model Content

[0004] To address the aforementioned problems, this utility model provides a soil and rock bearing capacity testing device.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a soil bearing capacity testing device, including a base plate, a bracket fixedly installed on the upper end of the base plate, a power device installed on the upper horizontal plate of the bracket, a buffer pressure head fixedly installed at the output end of the power device, a placement box corresponding to the buffer pressure head fixedly installed on the upper wall of the base plate, and positioning components are assembled on the upper wall of the base plate and around the placement box, and the output end of the positioning components penetrates the placement box and acts on the rock surface;

[0006] The buffer head includes a pressure head, a buffer block, a pressure plate, and a disc spring. The pressure head has a placement cavity inside, and the buffer block is movably assembled in the placement cavity. The upper and lower ends of the buffer block have elastic buffer cavities and damping cavities, respectively. A partition is fixedly installed in the damping cavity, and small holes are evenly distributed on the surface of the partition. Safety pins are evenly assembled between the lower wall of the buffer block and the lower wall of the placement cavity, and between the lower wall of the partition and the lower wall of the placement cavity. Hydraulic oil is filled around the safety pins in the placement cavity. The pressure plate is movably assembled in the elastic buffer cavity, and a disc spring is assembled between the lower wall of the pressure plate and the lower wall of the elastic buffer cavity. The pressure plate is fixedly installed at the output end of the power equipment.

[0007] Furthermore, the lower wall of the elastic buffer cavity is uniformly fixedly equipped with columns, the lower surface of the pressure plate is provided with slots corresponding to the columns, and the disc spring is sleeved on the outside of the columns.

[0008] Furthermore, a pressure head end plate is fixedly installed on the upper end of the pressure head, and a buffer block end plate is fixedly installed on the upper end of the buffer block, with the buffer block end plate located inside the placement cavity.

[0009] Furthermore, the positioning component includes an electric push rod, a push plate, and a positioning structure. The output end of the electric push rod is fixedly mounted with the push plate. The side wall of the placement box has a rectangular hole, and the push plate is movably assembled into the rectangular hole. The positioning structure is evenly assembled on the push plate.

[0010] Furthermore, the positioning structure includes a piston cylinder, a push rod, and a positioning head. The piston cylinder is fixedly installed on the outer wall of the push plate. The outer end of the piston cylinder is connected to an external oil pump through a pipeline. A piston push head is movably mounted on the outer side of the inner cavity of the piston cylinder. A moving plate is fixedly installed on the outer end of the push rod, and the moving plate is movably mounted on the inner side of the inner cavity of the piston cylinder. The positioning head is fixedly installed on the inner end of the push rod. The piston cylinder is filled with magnetorheological fluid between the piston push head and the moving plate.

[0011] Furthermore, the inner end of the positioning head is a spherical surface.

[0012] Furthermore, a protruding plate is fixedly installed in the middle of the inner cavity of the piston cylinder, and a magnetic guide plate corresponding to the piston cylinder is assembled on the upper surface of the base plate, with an electromagnet installed at the lower end of the magnetic guide plate.

[0013] The beneficial effects of using this utility model are:

[0014] This invention utilizes a positioning assembly consisting of an electric push rod, a push plate, and a magnetorheological fluid positioning structure. The positioning head can first adaptively contact and conform to the contour of the rock surface, and then the magnetorheological fluid is solidified by a magnetic field to rigidly lock the positioning head. This provides a uniform and reliable lateral constraint force for irregular rock samples, effectively preventing sample slippage or rotation during the test, and fundamentally ensuring the alignment of the applied load and the accuracy of the test results.

[0015] This invention integrates a safety pin triggering mechanism, a disc spring energy storage element, and a hydraulic damping chamber inside the buffer head, forming a progressive buffering path of "mechanical triggering - elastic energy storage - fluid energy consumption," which can reliably protect power equipment and force sensors from damage and extend the service life of the device. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the present invention.

[0017] Figure 2This is a front sectional view of the buffer pressure head of this utility model.

[0018] Figure 3 This is a three-dimensional schematic diagram of the positioning component of this utility model.

[0019] Figure 4 This is a cross-sectional view of the positioning structure of this utility model.

[0020] The reference numerals in the attached drawings include: 1. base plate, 2. bracket, 3. power equipment, 4. buffer head, 41. head, 411. safety pin, 412. head end plate, 42. buffer block, 421. partition plate, 422. small hole, 423. column, 424. buffer block end plate, 43. pressure plate, 431. slot, 44. disc spring, 5. placement box, 51. rectangular hole, 6. positioning assembly, 61. electric push rod, 62. push plate, 63. piston cylinder, 631. piston push head, 632. protruding plate, 64. push rod, 641. moving plate, 65. positioning head, 7. magnetic guide plate. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Reference Figures 1 to 4 A soil and rock bearing capacity testing device includes a base plate 1, a bracket 2 fixedly installed on the upper end of the base plate 1, a power device 3 installed on the upper horizontal plate of the bracket 2, a buffer pressure head 4 fixedly installed at the output end of the power device 3, a placement box 5 corresponding to the buffer pressure head 4 fixedly installed on the upper wall of the base plate 1, and positioning components 6 are assembled on the upper wall of the base plate 1 and around the placement box 5, and the output end of the positioning components 6 penetrates the placement box 5 and acts on the rock surface.

[0023] The rock to be tested is placed in the placement box 5, and the rock is positioned and fixed from the side by the positioning component 6. The power equipment 3 drives the buffer pressure head 4 to move down to apply pressure to the rock for load-bearing capacity testing.

[0024] The power unit 3 can be a hydraulic cylinder or an electric push rod.

[0025] When the pressure applied to the rock reaches its limit, the rock will break and generate a large impact force. The buffer head 4 can buffer this impact force and protect the equipment.

[0026] This device also needs to be equipped with a force sensor to measure the applied pressure and then calculate the rock bearing capacity.

[0027] The buffer head 4 includes a head 41, a buffer block 42, a pressure plate 43, and a disc spring 44. The head 41 has a placement cavity inside, and the buffer block 42 is movably assembled in the placement cavity. The upper and lower ends of the buffer block 42 are respectively provided with an elastic buffer cavity and a damping cavity. A partition plate 421 is fixedly installed in the damping cavity, and small holes 422 are evenly opened on the surface of the partition plate 421. Safety pins 411 are evenly assembled between the lower wall of the buffer block 42 and the lower wall of the placement cavity, and between the lower wall of the partition plate 421 and the lower wall of the placement cavity. Hydraulic oil is filled around the safety pins 411 in the placement cavity. The pressure plate 43 is movably assembled in the elastic buffer cavity, and a disc spring 44 is assembled between the lower wall of the pressure plate 43 and the lower wall of the elastic buffer cavity. The pressure plate 43 is fixedly installed at the output end of the power equipment 3.

[0028] Based on the type of rock, the bearing capacity range of that rock can be found. Based on this, a suitable safety pin 411 is selected so that the breaking pressure of the safety pin 411 is within or slightly greater than the above bearing capacity range. This ensures that when the rock breaks, the impact force generated can break the safety pin 411, thereby realizing the buffering function in the buffer head 4. Due to the characteristics of the safety pin 411, the safety pin 411 needs to be replaced before each test.

[0029] When the buffer head 4 is installed, the safety pin 411 restricts the position of the buffer block 42, preventing the buffer block 42 from moving within the placement cavity.

[0030] The pressure head 41 is the part that applies pressure to the rock. When the power equipment 3 operates, it drives the pressure plate 43 to move downward, which in turn drives the buffer pressure head 4 to move downward. When the buffer pressure head 4 contacts the rock surface, the pressure will first compress the disc spring 44 to store elastic potential energy, and then apply pressure to the rock until the rock breaks. The impact force generated by the rock breaking acts on the buffer pressure head 4, which will cause the safety pin 411 to break and no longer support the pressure head 41 and the buffer block 42. At the same time, it releases the elastic potential energy of the disc spring 44, generating a downward force to compensate for the upward impact of the rock breaking and avoid damage to the power equipment and force sensor. During this process, the position of the pressure plate 43 remains unchanged, and the pressure head 41 and the buffer block 42 will both undergo vertical displacement. For the damping chamber, hydraulic oil flows into the damping chamber through the small hole 422, generating huge flow resistance and continuously consuming impact energy. The disc spring 44 in the elastic buffer chamber plays an auxiliary buffering role.

[0031] Specifically, the lower wall of the elastic buffer cavity is uniformly fixed with columns 423, the lower surface of the pressure plate 43 is provided with slots 431 corresponding to the columns 423, and the disc spring 44 is sleeved on the outside of the columns 423.

[0032] Specifically, a pressure head end plate 412 is fixedly installed on the upper end of the pressure head 41, and a buffer block end plate 424 is fixedly installed on the upper end of the buffer block 42, with the buffer block end plate 424 located inside the placement cavity.

[0033] Specifically, the positioning component 6 includes an electric push rod 61, a push plate 62, and a positioning structure. The output end of the electric push rod is fixedly mounted with the push plate 62. A rectangular hole 51 is opened on the side wall of the placement box 5, and the push plate 62 is movably assembled in the rectangular hole 51. The positioning structure is evenly assembled on the push plate 62.

[0034] Specifically, the positioning structure includes a piston cylinder 63, a push rod 64, and a positioning head 65. The piston cylinder 63 is fixedly installed on the outer wall of the push plate 62. The outer end of the piston cylinder 63 is connected to an external oil pump through a pipeline. A piston push head 631 is movably mounted on the outer side of the inner cavity of the piston cylinder 63. A movable plate 641 is fixedly installed on the outer end of the push rod 64, and the movable plate 641 is movably mounted on the inner side of the inner cavity of the piston cylinder 63. The positioning head 65 is fixedly installed on the inner end of the push rod 64. The piston cylinder 63 is filled with magnetorheological fluid between the piston push head 631 and the movable plate 641.

[0035] Specifically, the inner end of the positioning head 65 is a spherical surface, which facilitates contact with the uneven surface of the rock and enables the application of force in multiple directions.

[0036] Specifically, a protruding plate 632 is fixedly installed in the middle of the inner cavity of the piston cylinder 63, and a magnetic guide plate 7 corresponding to the piston cylinder 63 is assembled on the upper surface of the base plate 1. An electromagnet is installed at the lower end of the magnetic guide plate 7.

[0037] After the rock is placed in the placement box 5, the electric push rod 61 moves the push plate 62 inward until it is close to the rock and then stops. Then, hydraulic oil is injected into the piston cylinder 63. Through the transmission of the piston push head 631 and the magnetorheological fluid, the push rod 64 and the positioning head 65 are moved until they contact the rock surface. Through multiple positioning heads 65 in different directions and positions, the rock can be stably positioned and its position defined. Then, the electromagnet is energized to make the surface of the magnetic plate 7 magnetic, and a magnetic field is applied to the piston cylinder 63, causing the magnetorheological fluid to turn into a solid, further increasing the strength and stability of the positioning head 65. Finally, it can be ensured that when the buffer pressure head 4 applies pressure to the rock, the rock position is fixed, and the pressure can be applied smoothly, making the result more accurate.

[0038] The convex plate 632 is provided so that when the magnetorheological fluid solidifies, the solidified magnetorheological fluid will not move within the piston cylinder 63 due to the restriction of the convex plate 632. At this time, there is no need to inject hydraulic oil or control the oil pressure from the outside, which can further improve the stability of rock positioning.

[0039] When the device detects rock fracturing (through data fluctuations from a force sensor or images captured by an external camera), it controls the electromagnet to be de-energized, causing the magnetic field to disappear. The magnetorheological fluid can then transform into a liquid state in a very short time. At this point, the convex plate 632 no longer acts as a limiter, allowing the positioning head 65 to retract under impact. The structure of the piston cylinder 63 forms a magnetorheological fluid damper, which, together with the buffering capacity of the hydraulic oil, protects the push plate and the positioning head.

[0040] The above content is only a preferred embodiment of this utility model. For those skilled in the art, many changes can be made in the specific implementation and application scope based on the concept of this utility model. As long as these changes do not depart from the concept of this utility model, they all fall within the protection scope of this utility model.

Claims

1. A soil and rock bearing capacity testing device, characterized in that: The device includes a base plate, a bracket is fixedly installed on the upper wall end of the base plate, a power device is installed on the upper horizontal plate of the bracket, a buffer pressure head is fixedly installed at the output end of the power device, a placement box corresponding to the buffer pressure head is fixedly installed on the upper wall of the base plate, and positioning components are assembled on the upper wall of the base plate and around the placement box, and the output end of the positioning components penetrates the placement box and acts on the rock surface. The buffer head includes a pressure head, a buffer block, a pressure plate, and a disc spring. The pressure head has a placement cavity inside, and the buffer block is movably assembled in the placement cavity. The upper and lower ends of the buffer block have elastic buffer cavities and damping cavities, respectively. A partition is fixedly installed in the damping cavity, and small holes are evenly distributed on the surface of the partition. Safety pins are evenly assembled between the lower wall of the buffer block and the lower wall of the placement cavity, and between the lower wall of the partition and the lower wall of the placement cavity. Hydraulic oil is filled around the safety pins in the placement cavity. The pressure plate is movably assembled in the elastic buffer cavity, and a disc spring is assembled between the lower wall of the pressure plate and the lower wall of the elastic buffer cavity. The pressure plate is fixedly installed at the output end of the power equipment.

2. The soil and rock bearing capacity testing device according to claim 1, characterized in that: The lower wall of the elastic buffer cavity is uniformly fixed with columns, the lower surface of the pressure plate is provided with slots corresponding to the columns, and the disc spring is sleeved on the outside of the columns.

3. The soil and rock bearing capacity testing device according to claim 1, characterized in that: A pressure head end plate is fixedly installed on the upper end of the pressure head, and a buffer block end plate is fixedly installed on the upper end of the buffer block, with the buffer block end plate located inside the placement cavity.

4. The soil and rock bearing capacity testing device according to claim 1, characterized in that: The positioning component includes an electric push rod, a push plate, and a positioning structure. The output end of the electric push rod is fixedly mounted with the push plate. The side wall of the placement box has a rectangular hole, and the push plate is movably assembled into the rectangular hole. The positioning structure is evenly assembled on the push plate.

5. The soil and rock bearing capacity testing device according to claim 4, characterized in that: The positioning structure includes a piston cylinder, a push rod, and a positioning head. The piston cylinder is fixedly installed on the outer wall of the push plate. The outer end of the piston cylinder is connected to an external oil pump through a pipeline. A piston push head is movably mounted on the outer side of the inner cavity of the piston cylinder. A moving plate is fixedly installed on the outer end of the push rod and is movably mounted on the inner side of the inner cavity of the piston cylinder. The positioning head is fixedly installed on the inner end of the push rod. The piston cylinder is filled with magnetorheological fluid between the piston push head and the moving plate.

6. The soil and rock bearing capacity testing device according to claim 5, characterized in that: The inner end of the positioning head is a spherical surface.

7. The soil and rock bearing capacity testing device according to claim 5, characterized in that: A protruding plate is fixedly installed in the middle of the inner cavity of the piston cylinder, and a magnetic guide plate corresponding to the piston cylinder is assembled on the upper surface of the base plate. An electromagnet is installed at the lower end of the magnetic guide plate.

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