Bio-based porous elastic mixture roadbed test device

Abstract

This invention relates to the field of road material testing technology, specifically disclosing a bio-based porous elastic mixture roadbed testing device. The device includes a base plate with two parallel upright plates fixedly connected to its upper side. Each upright plate has a clamping device rotatably connected to one side. The two clamping devices are correspondingly arranged and used to clamp precast specimens. Each clamping device has a torque application device on one side, and the torque applied by the two torque application devices to the clamping devices is always opposite. This invention, by setting two torque application devices that always apply opposite torque forces, can perform torsional and fatigue performance tests on precast specimens, as well as permeability tests. It can also test the compressive strength, shear strength, and tensile strength of repair plates. By comparing multiple repair plates, it can determine which ratio of repair plate has the optimal performance in each aspect.

Description

Technical Field

[0001] This invention relates to the field of road material testing technology, and in particular to a testing device for bio-based porous elastic mixture roadbeds. Background Technology

[0002] In the field of road engineering, after repairing existing roadbeds with novel materials such as bio-based porous elastic mixtures, a systematic evaluation of the comprehensive road performance of the repaired material is required to select the optimal material mix. However, existing testing devices, such as the testing device disclosed in CN115876616B that tests the mechanical behavior of road repairs through friction and normal pressure, can only test the compressive and shear strength of the repaired material, but cannot test the overall torsional stiffness of the repaired roadbed, nor can they test the interfacial bond strength and permeability of the repaired material. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a bio-based porous elastic mixture roadbed testing device.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A bio-based porous elastic mixture roadbed test device includes a base plate, two parallel vertical plates are fixedly connected to the upper side of the base plate, and a clamping device is rotatably connected to one side of each vertical plate. The two clamping devices are correspondingly arranged and used to clamp the precast specimens. Each clamping device is provided with a torque application device on one side, and the torque applied by the two torque application devices to the clamping devices is always opposite.

[0005] Preferably, a flat plate is fixedly connected to the upper side of the two upright plates. The flat plate is provided with a sliding groove, and a slider is slidably connected in the sliding groove. A first hydraulic cylinder is mounted on the slider, and the telescopic end of the first hydraulic cylinder is fixedly connected to a pressure plate. A push-pull device is mounted on the flat plate, which is used to drive the slider to slide back and forth in the sliding groove.

[0006] Preferably, the pressure plate has a cavity inside, and the bottom of the pressure plate has multiple water outlet holes communicating with the cavity. A water inlet pipe communicating with the cavity is provided on one side of the pressure plate.

[0007] Preferably, the pressure plate has multiple grooves, and the water outlet holes are arranged in the grooves one by one.

[0008] Preferably, the bottom surface of the pressure plate is rough.

[0009] Preferably, the precast specimen includes an existing roadbed material test plate, which has at least two simulated repair grooves, and the simulated repair grooves contain a repair plate of bio-based porous elastic mixture.

[0010] Preferably, a water collection device is provided at the bottom of the inner side of the simulated repair trench. The water collection device includes a water collection tray, a water collection trough on the water collection tray, and a water collection pipe at the center of the water collection trough. The water collection pipe penetrates downward through the existing roadbed material test plate.

[0011] Preferably, the water collection pipe has multiple sliding holes on its wall, which are evenly arranged around the axis of the water collection pipe and the direction of the sliding holes is consistent with the axis of the water collection pipe. Sliding rods are slidably connected inside the sliding holes, and the lower end of the sliding rods is a spherical surface. Each sliding rod is equipped with a strain gauge pressure sensor.

[0012] Preferably, the water collection tray is provided with multiple relief grooves, and each relief groove is provided with a transition plate, with the upper end of the slide rod being fixedly connected to the transition plate in a corresponding manner.

[0013] Preferably, a plurality of water receiving buckets are mounted on the upper side of the base plate, and the water receiving buckets are equipped with drain pipes. A top extension device is installed inside the water receiving buckets. The top extension device includes a second hydraulic cylinder, which is vertically installed inside the water receiving buckets. The telescopic end of the second hydraulic cylinder is fixedly connected to a ball.

[0014] The beneficial effects of the present invention are as follows: The present invention can perform torsional and fatigue performance tests on precast specimens by setting two torque application devices that always apply opposite torque forces, and can also perform water permeability tests on precast specimens. At the same time, it can also test the compressive strength, shear strength and tensile strength of the repair plate. By comparing multiple repair plates, it can determine which ratio of repair plate has the best performance in each aspect. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the basic structure of the present invention; Figure 2 yes Figure 1 Usage diagram; Figure 3 This is a schematic diagram of the basic structure of the pressure plate; Figure 4 This is a schematic diagram of the basic structure of the precast specimen; Figure 5 This is a schematic diagram of the basic structure of a water collection device. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0017] like Figures 1-5As shown, the bio-based porous elastic mixture roadbed testing device provided in this embodiment includes a base plate 1. Two parallel and oppositely arranged upright plates 2 are vertically fixedly connected to the upper side of the base plate 1. Each upright plate 2 has a rotating hole on one side, and the two rotating holes are coaxially arranged. A rotating shaft is rotatably connected in each rotating hole, and a clamping device 5 is fixedly connected to one end of each rotating shaft. The two clamping devices 5 are correspondingly arranged and used to clamp the precast specimen 100. Each clamping device 5 has a torque applying device 51 on one side. The torque applying device 51 can be a hydraulic swing cylinder or a servo motor drive system. The torque applied by the two torque applying devices 51 to the clamping devices 5 is always opposite.

[0018] Preferably, a flat plate 3 is fixedly connected to the upper sides of the two upright plates 2. The flat plate 3 has a groove 31, within which a slider 33 is slidably connected. A vertically arranged first hydraulic cylinder 34 is mounted on the slider 33. The telescopic end of the first hydraulic cylinder 34 is fixedly connected to a pressure plate 4. A push-pull device 35 is mounted on the flat plate 3, which drives the slider 33 to reciprocate within the groove 31. This allows the pressure plate 4 to be precisely aligned with any repair plate 103 on the precast specimen 100.

[0019] The precast specimen 100 includes an existing roadbed material test slab 101 precast from the original roadbed material. Two or more simulated repair grooves 102 are symmetrically pre-formed on the upper surface of the test slab 101. Each simulated repair groove 102 is filled with a different proportion of bio-based porous elastic mixture and cured to form a repair slab 103. This allows for direct comparison of the performance differences of repair slabs 103 formed with different proportions of repair materials under the same test conditions.

[0020] The pressure plate 4 has an internal cavity 41. Multiple water outlet holes 43 communicating with the cavity 41 are located on the bottom of the pressure plate 4. A water inlet pipe 42 communicating with the cavity 41 is located on one side of the pressure plate 4, and the water inlet pipe 42 is connected to an external water source. To prevent the water outlet holes 43 from being blocked and to ensure uniform water distribution, multiple grooves 44 are formed on the bottom surface of the pressure plate 4, with each water outlet hole 43 corresponding to one groove 44. Simultaneously, to provide sufficient friction during shear testing, the bottom surface of the pressure plate 4 is machined to a rough surface.

[0021] The simulated repair trench 102 has a water collection device 8 at the bottom inside. The water collection device 8 includes a water collection plate 81, a water collection trough 82 on the water collection plate 81, and a water collection pipe 83 at the center of the water collection trough 82. The water collection pipe 83 penetrates downward through the existing roadbed material test plate 101.

[0022] The water collecting pipe 83 has multiple sliding holes on its wall, which are evenly arranged around the axis of the water collecting pipe 83 and oriented in the same direction as the axis of the water collecting pipe 83. Sliding rods 85 are slidably connected within the sliding holes. The lower end of each sliding rod 85 extends beyond the bottom surface of the water collecting pipe 83 and is spherical. Each sliding rod 85 is equipped with a strain gauge pressure sensor 86. The water collecting tray 81 has multiple clearance grooves, each containing a transition plate 84. The upper ends of the sliding rods 85 are fixedly connected to the corresponding transition plates 84.

[0023] Multiple water collection buckets 6 are mounted on the upper side of the base plate 1. Drain pipes 61 are provided at the bottom of the side walls of each water collection bucket 6 for draining leaked water. A lifting device 7 is installed inside each water collection bucket 6. The lifting device 7 includes a second hydraulic cylinder 71, which is vertically installed inside the water collection bucket 6. The telescopic end of the second hydraulic cylinder 71 is fixedly connected to a sphere 72. The position of the sphere 72 is coaxial with the water collection pipe 83. The sphere 72 can maintain adaptive contact with the spherical surface at the lower end of all sliding rods 85.

[0024] The bio-based porous elastic mixture roadbed testing device of this embodiment can perform torsional and fatigue performance tests on precast specimens 100. Precast specimens 100, containing repair plates 103 with different proportions, are prepared according to specifications, and both ends of the precast specimens 100 are firmly clamped by clamping devices 5. First, two applying devices 51 output equal and opposite torque forces to apply graded or continuous torsional loading to the precast specimens 100. By recording the relationship curve between torque and torsion angle, the overall torsional stiffness of the precast specimens 100 can be directly obtained. After the torque is removed, the deformation recovery of the precast specimens 100 is monitored to evaluate the self-recovery performance of different materials. The torque is continuously increased until the precast specimens 100 fail; the resulting ultimate torque is the overall strength of the precast specimens 100 against torsional fracture. To simulate the repeated torsional and shear effects caused by vehicle turning on the roadbed, the two torque applying devices 51 are cyclically loaded in opposite directions throughout the process, with the torque directions of the two torque applying devices 51 always being opposite. After the alternating fatigue loading is stopped after a predetermined number of cycles, the remaining performance of the repair plate 103 can be obtained through subsequent tests, thereby directly comparing the fatigue resistance performance of different repair plates 103.

[0025] After the fatigue resistance test is completed by reciprocating loading, the precast specimen 100 is kept under a certain torque force, and the push-pull device 35 is activated to drive the slider 33, so that the pressure plate 4 is positioned directly above the target repair plate 103. Then, the first hydraulic cylinder 34 drives the pressure plate 4 to apply vertical pressure to the repair plate 103, thus obtaining the compressive bearing capacity of the repair plate 103 under torsional conditions. While maintaining the pressure plate 4 applying vertical pressure to the repair plate 103, the push-pull device 35 is activated to drive the slider 33 to move horizontally. Due to the interlocking friction between the rough surface of the bottom of the pressure plate 4 and the upper surface of the repair plate 103, the pressure plate 4 will simultaneously apply a horizontal thrust to the repair plate 103. Thus, the shear resistance of the repair plate 103 under torsional conditions can be obtained.

[0026] The bio-based porous elastic mixture roadbed testing device of this embodiment can also perform permeability testing on the precast specimen 100. Using the push-pull device 35, the pressure plate 4 is moved above the repair plate 103 to be tested, and the pressure plate 4 is lightly pressed against the surface of the precast specimen 100. Water at a specified head pressure is injected into the cavity 41 of the pressure plate 4 through the water inlet pipe 42. The water is evenly released onto the surface of the repair plate 103 through the bottom groove 44 and the water outlet hole 43 and permeates downwards. The water permeating through the repair plate 103 is collected by the water collection tray 81 below it, flows through the water collection trough 82 to the water collection pipe 83, and finally falls into the water receiving bucket 6. By measuring the amount of water seepage within a specified time, the permeability performance of different repair plates 103 is obtained. The bio-based porous elastic mixture roadbed testing device of this embodiment can also perform interfacial tensile strength testing on the precast specimen 100 under non-uniform deformation. The tensile strength test can be performed with or without applied torque force on the precast specimen 100. When it is necessary to test the interfacial normal bond strength between the repair plate 103 and the existing roadbed material test plate 101, the second hydraulic cylinder 71 in the corresponding water receiving bucket 6 is activated, pushing the ball 72 at its top upward. The ball 72 first adaptively contacts all the spherical surfaces at the lower ends of all the slide bars 85, and then continues to apply an upward thrust. This thrust is evenly transmitted to the bottom surface of the repair plate 103 through the slide bars 85 and the transition plate 84, forming an upward normal pull-out force. The magnitude of the force is accurately measured by the strain gauge pressure sensor 86 on the slide bar 85. In this way, the interfacial tensile bond strength can be measured.

[0027] When the precast specimen 100 warps and deforms under torsion, resulting in uneven gaps between the repair plate 103 and the existing roadbed material test plate 101, the lower ends of each slide rod 85 are not on the same horizontal plane. Through the point contact between the sphere 72 and the spherical surface at the lower end of the slide rod 85 in this embodiment, the top stretching force is adaptively and evenly distributed to all slide rods 85, thereby ensuring that the pull-out strength test results are accurate and reliable even under non-uniform deformation conditions.

[0028] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A biobased porous elastic mix subgrade testing device, characterized by: Includes a base plate (1), on which two parallel upright plates (2) are fixedly connected. Each upright plate (2) is rotatably connected to a clamping device (5) on one side. The two clamping devices (5) are correspondingly arranged and used to clamp the precast specimen (100). Each clamping device (5) is provided with a torque applying device (51) on one side. The torque applied by the two torque applying devices (51) to the clamping device (5) is always opposite.

2. The bio-based porous elastic mix subgrade testing device according to claim 1, characterized in that: The two upright plates (2) are fixedly connected to a flat plate (3) on their upper sides. The flat plate (3) is provided with a sliding groove (31). A slider (33) is slidably connected in the sliding groove (31). A vertically arranged first hydraulic cylinder (34) is mounted on the slider (33). The telescopic end of the first hydraulic cylinder (34) is fixedly connected to a pressure plate (4). A push-pull device (35) is mounted on the flat plate (3). The push-pull device (35) is used to drive the slider (33) to slide back and forth in the sliding groove (31).

3. The bio-based porous elastic mixture roadbed test device according to claim 2, characterized by: The pressure plate (4) has a cavity (41) inside, and the bottom of the pressure plate (4) has multiple water outlet holes (43) communicating with the cavity (41). The side of the pressure plate (4) has a water inlet pipe (42) communicating with the cavity (41).

4. The bio-based porous elastic mixture roadbed test device according to claim 3, characterized by: The pressure plate (4) is provided with multiple grooves (44), and the water outlet holes (43) are arranged one by one in the grooves (44).

5. The bio-based porous elastic mixture roadbed test device according to claim 4, characterized by: The bottom surface of the pressure plate (4) is rough.

6. The bio-based porous resilient mix subgrade testing device of claim 3, wherein: The precast specimen (100) includes an existing roadbed material test plate (101), on which at least two simulated repair grooves (102) are provided, and a repair plate (103) of bio-based porous elastic mixture is provided in the simulated repair grooves (102).

7. The bio-based porous elastic mixture roadbed test device according to claim 6, characterized in that: The simulated repair trench (102) has a water collection device (8) at the bottom inside. The water collection device (8) includes a water collection tray (81), a water collection trough (82) on the water collection tray (81), and a water collection pipe (83) at the center of the water collection trough (82). The water collection pipe (83) penetrates downward through the existing roadbed material test plate (101).

8. The bio-based porous resilient mix subgrade testing device of claim 7, wherein: The water collection pipe (83) has multiple sliding holes on its wall. The sliding holes are evenly arranged around the axis of the water collection pipe (83) and the direction of the sliding holes is consistent with the direction of the axis of the water collection pipe (83). The sliding rod (85) is slidably connected in the sliding hole. The lower end of the sliding rod (85) is a spherical surface. Each sliding rod (85) is equipped with a strain gauge pressure sensor (86).

9. The bio-based porous resilient mix subgrade testing device of claim 8, wherein: The water collection tray (81) is provided with multiple clearance grooves, and each clearance groove is provided with a transition plate (84). The upper end of the slide rod (85) is fixedly connected to the transition plate (84) in a corresponding manner.

10. The biobased porous elastomeric mix subgrade testing device of claim 8, wherein: The base plate (1) is equipped with multiple water collection buckets (6) on its upper side. The water collection buckets (6) are provided with drain pipes (61). The water collection buckets (6) are equipped with a top extension device (7). The top extension device (7) includes a second hydraulic cylinder (71). The second hydraulic cylinder (71) is vertically installed in the water collection buckets (6). The telescopic end of the second hydraulic cylinder (71) is fixedly connected to a ball (72).

Images