Compression resistance detection device and detection method for carbonaceous soft rock roadbed structure

Abstract

The invention discloses a carbonaceous soft rock roadbed structure compression resistance detection device and detection method, and belongs to the field of compression testing machines. The device comprises a rack, a detection workbench arranged on the rack, and a pressurization assembly installed on the rack. The detection workbench is provided with a through hole, and the inner wall surface of the through hole is provided with a plurality of convex supporting blocks which are annularly distributed. The movable carrying table moves up and down in the axial direction of the through hole; the bottom side surface of the movable carrying table is connected with a driving mechanism for driving the movable carrying table to move; during detection, the columnar sample shrinks into the through hole, and the top part of the columnar sample extends out of the upper surface of the detection workbench. According to the invention, by designing the detection workbench with the through hole, a semi-closed detection space is created; when the pressurizing assembly applies pressure to the sample and damages the sample, most of disintegrated fragments are limited in the through hole and the cavity below the through hole and cannot splash all around.

Description

Technical Field

[0001] This invention relates to the field of pressure testing machines, and in particular to a device and method for testing the compressive strength of carbonaceous soft rock subgrade structures. Background Technology

[0002] Carbonaceous soft rock, as a special type of roadbed filling material, is prone to softening, disintegration, and strength reduction when exposed to water. Therefore, its application in roadbed engineering projects such as highways and railways requires strict quality control. Compressive strength is one of the key indicators for evaluating the performance of its roadbed structure.

[0003] To accurately reflect the actual structural strength and bearing capacity of the roadbed after on-site compaction, existing methods often involve directly drilling undisturbed columnar samples from the roadbed for compressive strength testing. However, existing pressure testing equipment for this purpose has limitations when testing undisturbed columnar samples of special materials such as carbonaceous soft rock. For example, CN111650053A discloses a concrete pressure testing machine whose structure includes a hydraulic lifter, pressure plate, pressure testing platform, display controller, support, balance support rod, and placement platform structure, with the hydraulic lifter mounted on the support. When testing undisturbed columnar samples using this pressure testing machine, if the sample fails during testing, the disintegration or splashing fragments lack effective protection and restraint, potentially posing safety hazards to the equipment or operators, and affecting the cleanliness of the testing environment and subsequent cleanup. Summary of the Invention

[0004] This invention provides a device and method for testing the compressive strength of carbonaceous soft rock roadbed structures, which can solve the problem that in the prior art, when a columnar undisturbed sample is damaged during testing, there is a lack of effective protection and restraint for the disintegration or splashing fragments.

[0005] A compressive strength testing device for carbonaceous soft rock subgrade structures includes a frame, a testing workbench mounted on the frame, and a pressurizing assembly mounted on the frame. The pressurizing assembly applies pressure to a columnar sample placed on the testing workbench. The testing workbench has a through hole, and the inner wall of the through hole is provided with multiple annularly distributed convex support blocks. It also includes a movable platform that moves up and down along the axial direction of the through hole, and the bottom side of the movable platform is connected to a driving mechanism that drives its movement. During testing, the columnar sample retracts into the through hole, and its top part protrudes from the upper surface of the testing workbench.

[0006] Furthermore, the pressurizing assembly includes a pressure block and a pressurizing cylinder that drives the pressure block to move up and down in a vertical direction, and a pressure sensor is provided between the output end of the pressurizing cylinder and the pressure block.

[0007] Furthermore, the bottom of the through hole extends into the interior of the frame, and the drive mechanism includes a support plate installed in the frame. A lifting cylinder is mounted on the upper surface of the support plate, and the output end of the lifting cylinder is connected to the side of the bottom of the movable platform.

[0008] Furthermore, a mounting cavity communicating with the through hole is provided at the bottom of the frame, and the support plate is installed in the mounting cavity; the upper surfaces at both ends of the support plate are provided with bent portions, and support beams supporting the lower surfaces at both ends of the support plate are provided on the two opposite inner walls of the mounting cavity; locking bolts are threaded onto the bent portions, and pins are provided at the ends of the locking bolts; pin holes for inserting the pins are provided on the inner walls of the mounting cavity.

[0009] Furthermore, the upper surface of the support beam is provided with a limiting protrusion, and the side of the limiting protrusion near the support plate is provided with a positioning hole, and the side of the support plate is provided with a positioning post that can be inserted into the positioning hole.

[0010] Furthermore, a gap is formed between two adjacent convex support blocks, and a support portion passing through the gap is provided on the periphery of the movable platform.

[0011] Furthermore, a positioning mechanism is provided on the upper surface of the testing worktable located at the through hole. The positioning mechanism is used to position the cylindrical sample placed in the through hole. The positioning mechanism includes a semi-circular side guard installed on the upper surface of the testing worktable. A pair of parallel strip side guards are provided at both ends of the semi-circular side guard. A guide portion is provided at the end of the strip side guard. The semi-circular side guard, the strip side guard, and the guide portion are integrally formed. The two guide portions are in the shape of an "eight". The semi-circular side guard and the strip side guard cooperate to form a "U" shape. The inner diameter of the semi-circular side guard is larger than the diameter of the through hole, and the two are coaxially arranged.

[0012] Furthermore, a first push rod structure is provided on the inner wall surface of the junction of the semi-circular side guard and the strip side guard, and a second push rod structure is provided on the inner wall surface of the semi-circular side guard located between the two first push rod structures. The first push rod structure and the second push rod structure are identical in structure. The first push rod structure includes a telescopic sleeve rod, and the end of the telescopic sleeve rod is provided with a spherical abutment that abuts against the cylindrical sample. The telescopic sleeve rod includes an inner sleeve and an outer sleeve that are sealed together. The inner wall surface of the outer sleeve is provided with a limiting protrusion ring that restricts the movement path of the inner sleeve. A groove is provided on the upper surface of the semi-circular side guard and / or the strip side guard. A telescopic sleeve that extends and retracts in the vertical direction is installed in the groove. An indicator block is connected to the top of the telescopic sleeve. The telescopic sleeve and the telescopic sleeve rod are connected.

[0013] Furthermore, the outer wall of the semi-circular side guard is provided with a mounting ear, and a mounting bolt passes through the mounting hole of the mounting ear; the upper surface of the testing workbench is provided with an annular groove at the port of the threaded hole that is threaded to the mounting bolt, and the mounting ear located on the periphery of the mounting hole is provided with an annular positioning boss that is inserted into the annular groove.

[0014] A method for testing the compressive strength of carbonaceous soft rock subgrade structures, characterized in that it employs a compressive strength testing device for carbonaceous soft rock subgrade structures as described above, specifically including: Step 1: Use a sampling device to collect columnar samples of the active carbonaceous soft rock subgrade; Step 2: Place the cylindrical sample onto the upper surface of the testing stage, and control the movable stage to move upward until its upper surface and the upper surface of the testing stage are coplanar; Step 3: Control the columnar sample to move to the upper surface of the movable stage, and then control the movable stage to slowly move downward to the maximum stroke. At this time, the bottom end of the columnar sample is against the convex support block. Step 4: Control the pressurization component to move downwards to complete the test.

[0015] 1. This invention creates a semi-enclosed testing space by designing a testing worktable with through holes; when the pressurizing component applies pressure to the sample and causes it to break, most of the disintegrating fragments are confined within the through holes and cannot splash outwards.

[0016] 2. This invention, through the cooperation of the movable platform and the driving mechanism, first places the cylindrical sample on the detection worktable, then pushes the cylindrical sample along the upper surface of the detection worktable to the upper surface of the movable platform, and then the driving mechanism controls the movable platform to slowly and smoothly descend until the convex support block supports the bottom surface of the cylindrical sample. This avoids the impact caused by the sample falling freely, prevents accidental damage caused by improper handling before detection, and ensures the accuracy of the detection data. Attached Figure Description

[0017] Figure 1 A schematic diagram of the compressive strength testing device is provided for this invention. Figure 1 ; Figure 2 Provided for the present invention Figure 1 The main view; Figure 3 Provided for the present invention Figure 2 Draw a sectional view from AA; Figure 4 Provided for the present invention Figure 2 Enlarged view of a section at point C; Figure 5 A schematic diagram of the mating structure of the movable platform and the through hole is provided for this invention; Figure 6A schematic diagram of the compressive strength testing device is provided for this invention. Figure 2 ; Figure 7 Provided for the present invention Figure 6 Enlarged view of a portion of point A in the middle; Figure 8 Provided for the present invention Figure 7 The main view; Figure 9 Provided for the present invention Figure 8 Enlarged view of section B in the middle.

[0018] Explanation of reference numerals in the attached figures: 1-Frame, 2-Inspection workbench, 3-Semi-circular side guard, 11-Mounting cavity, 12-Pressure assembly, 20-Through hole, 21-Protruding support block, 22-Movable platform, 23-Annular groove, 24-Threaded hole, 30-Strip side guard, 31-Guide part, 32-Mounting ear, 33-Mounting bolt, 34-Telescopic sleeve rod, 35-Spherical abutment, 100-Columnar sample, 111-Support plate, 112-Lifting cylinder, 113-Bending part, 114-Support beam, 115-Limiting protrusion, 116-Locking bolt, 211-Gap, 221-Support part, 24-Threaded hole. Detailed Implementation

[0019] The specific embodiments of the present invention will be described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0020] Example 1: As Figures 1 to 4 As shown in the figure, the present invention provides a compressive strength testing device for carbonaceous soft rock subgrade structures, which mainly includes a frame 1, a testing workbench 2, and a pressurizing component 12. In order to solve the problems of flying debris, poor safety, and difficulty in cleaning during sample testing in the prior art, the present invention provides a through hole 20 on the testing workbench 2. The inner wall of the through hole 20 is provided with a plurality of annularly distributed convex support blocks 21. During testing, a columnar sample 100 is placed in the through hole 20 and supported by the convex support blocks 21 provided in the through hole 20. Then, the pressurizing component 12 is controlled to apply pressure to the columnar sample 100 placed in the through hole 20. This device completes the control of most of the testing process in a relatively confined space, effectively constraining and collecting debris.

[0021] The convex support block 21 is used to support the columnar sample 100 from below, forming a stable lower fulcrum so that pressure can be applied vertically to both ends of the sample.

[0022] Because the columnar sample 100 has a high density and height, it is quite heavy. When the columnar sample 100 is placed directly into the through hole 20, it will be damaged due to the impact of its weight on the convex support block 21. A movable platform 22 is also provided, which moves up and down along the axial direction of the through hole 20. The bottom side of the movable platform 22 is connected to a drive mechanism that drives its movement. Based on the arrangement of the movable platform 22 and the drive mechanism, when placing the sample, the movable platform 22 can be raised to be flush with the upper surface of the detection worktable 2, and the sample can be rolled into or pushed onto its upper surface. Then, the drive mechanism controls the movable platform 22 to slowly descend, smoothly delivering the sample to the predetermined detection position supported by the convex support block 21. This action enables the columnar sample 100 to be placed smoothly and controllably into the through hole 20, and avoids direct falling impact.

[0023] In actual operation, to facilitate the removal of the damaged columnar sample 100 from the through hole 20 after the test is completed, such as... Figure 5 A gap 211 is formed between two adjacent convex support blocks 21. A support portion 221 is provided on the periphery of the movable stage 22, passing through the gap 211. The gap 211 allows the movable stage 22 to move up and down through the convex support blocks 21. In the above description, when it is necessary to push the columnar sample 100 out from the top of the through hole 20, the movable stage 22 is controlled to move upwards in the drive mechanism; when it is necessary to clean the convex support blocks 21 and the inner wall of the through hole 20, the movable stage 22 is controlled to move downwards in the drive mechanism until it is completely disengaged from the through hole 20.

[0024] The movable stage 22 is a circular plate. Based on the setting of the movable stage 22, when the columnar sample 100 is placed vertically on the movable stage 22, it is convenient to manually adjust the center of the circular plate to coincide with the central axis of the columnar sample 100, which facilitates the positioning of the columnar sample 100.

[0025] Specifically, the pressurizing assembly 12 includes a pressure block, a pressurizing cylinder that drives the pressure block to move up and down vertically, and a pressure sensor disposed between the output end of the pressurizing cylinder and the pressure block. The pressurizing cylinder provides a stable downward pressure, and the pressure block uniformly transmits the pressure to the top of the sample. The pressure sensor is used to measure and record the pressure value applied to the sample in real time and accurately.

[0026] To facilitate the smooth up-and-down movement of the movable platform 22, the bottom of the through hole 20 extends into the interior of the frame 1. The driving mechanism provided by the present invention includes a support plate 111 installed in the frame 1. A lifting cylinder 112 is installed on the upper surface of the support plate 111, and the output end of the lifting cylinder 112 is connected to the bottom side of the movable platform 22.

[0027] It is understood that when cleaning the convex support block 21, the inner wall of the through hole 20, and the movable platform 22, the entire drive mechanism can be moved out from below the through hole 20. To achieve this, the present invention provides an installation cavity 11 communicating with the through hole 20 below the frame 1, and a support plate 111 is installed in the installation cavity 11. Bends 113 are provided on the upper surfaces of both ends of the support plate 111, and support beams 114 supporting the lower surfaces of both ends of the support plate 111 are provided on the two opposite inner walls of the installation cavity 11. Locking bolts 116 are threaded onto the bends 113, and pins are provided at the ends of the locking bolts 116. Pin holes for inserting the pins are provided on the inner walls of the installation cavity 11. The support beams 114 support the support plate 111 from below and bear the main load. The cooperation of the locking bolts 116 and the pins locks the support plate 111 to the frame 1 from the side, preventing horizontal movement or shaking. This design ensures structural rigidity while allowing the entire drive mechanism to be removed from the mounting cavity 11 as a whole, facilitating inspection and maintenance.

[0028] To achieve rapid and precise positioning of the support plate 111 during installation, a limiting protrusion 115 is provided on the upper surface of the support beam 114. A positioning hole is provided on the side of the limiting protrusion 115 near the support plate 111, and a positioning post is provided on the side of the support plate 111 to be inserted into the positioning hole. The limiting protrusion 115 and its positioning hole cooperate with the positioning post on the side of the support plate 111 to play the role of pre-positioning and error prevention. When the support plate 111 is placed into the installation cavity 11, the positioning post can automatically guide it to fall into the correct position, simplifying the installation process and ensuring the alignment of the lifting cylinder 112 and the movable platform 22.

[0029] A method for testing the compressive strength of carbonaceous soft rock subgrade structures, specifically including: Step 1: Use a sampling device to collect 100 columnar samples of the active carbonaceous soft rock subgrade; Step 2: Place the columnar sample 100 on the upper surface of the detection stage 2, and control the movable stage 22 to move upward until its upper surface and the upper surface of the detection stage 2 are coplanar; Step 3: Control the columnar sample 100 to move to the upper surface of the movable stage 22, and then control the movable stage 22 to slowly move downward to the maximum stroke. At this time, the bottom end of the columnar sample 100 is against the convex support block 21. At this time, most of the columnar sample 100 has been retracted into the through hole 20, with only a small part of the top exposed. Step 4: Control the pressurizing cylinder of the pressurizing component 12 to drive the pressure block downward to apply axial pressure to the exposed part of the columnar sample 100, and record the pressure-displacement data through the pressure sensor until the sample is destroyed; the fragments of the columnar sample 100 are effectively confined in the through hole 20 and the space below it.

[0030] Example 2, based on Example 1, to facilitate the accurate alignment and placement of the columnar sample 100 onto the movable stage 22, as follows: Figures 6-8 A positioning mechanism is provided on the upper surface of the inspection workbench 2 located at the through hole 20. The positioning mechanism includes a semi-circular side block 3 installed on the upper surface of the inspection workbench 2. A pair of parallel strip side blocks 30 are connected to both ends of the semi-circular side block 3. A guide part 3 is provided at the end of the strip side block 30. The semi-circular side block 3, the strip side block 30 and the guide part 31 are integrally formed. The two guide parts 31 have an "eight" shaped opening. The semi-circular side block 3 and the strip side block 30 cooperate to form a "U" shaped structure. The inner diameter of the semi-circular side block 3 is larger than the diameter of the through hole 20, and the two are coaxially arranged. A first push rod structure is provided on the inner wall surface at the junction of the semi-circular side block 3 and the strip side block 30. A second push rod structure is provided on the inner wall surface of the semi-circular side block 3 located between the two first push rod structures. The first push rod structure and the second push rod structure have the same structure.

[0031] During operation, the operator can first push the columnar sample 100 along the figure-eight shaped guide part 31 until the outer wall surface of the columnar sample 100 touches the ends of the first push rod structure and the second push rod structure.

[0032] like Figure 9 The first push rod structure includes a telescopic sleeve 34, the end of which is provided with a spherical abutment 35 that can abut against the cylindrical sample 100; the telescopic sleeve 34 is composed of an inner sleeve and an outer sleeve that are sealed together, and the inner wall of the outer sleeve is provided with a limiting protrusion ring that restricts the movement path of the inner sleeve; a telescopic sleeve that extends and retracts in the vertical direction is installed in the groove on the upper surface of the semi-circular side stop 3, and an indicator block is connected to its top, and the telescopic sleeve is connected to the three telescopic sleeves 34; when the cylindrical sample 100 is pushed in, the three telescopic sleeves 34 are controlled to complete the maximum contraction under the squeezing action of the side wall of the cylindrical sample 100. At this time, under the action of pressure, the upper surface of the indicator block is controlled to protrude from the upper surface of the semi-circular side stop 3. That is, when the upper surface of the indicator block is observed to protrude from the upper surface of the semi-circular side stop 3, it indicates that the cylindrical sample 100 has been completely centered.

[0033] To achieve rapid, accurate, and repeatable positioning of the positioning mechanism on the testing workbench; such as Figure 7A mounting lug 32 is provided on the outer wall of the semi-circular side stop 3, and a mounting bolt 33 passes through the mounting hole of the mounting lug 32. A threaded hole 24 that mates with the mounting bolt 33 is provided on the upper surface of the inspection workbench 2, and an annular groove 23 is provided at the end of the threaded hole 24. An annular positioning boss that can be inserted into the annular groove 23 is provided on the mounting lug 32 located around the mounting hole. During installation, the annular positioning boss is first placed into the annular groove 23 to achieve radial limiting and initial alignment of the positioning mechanism, and then the mounting bolt 33 is tightened. This ensures the coaxiality of the semi-circular side stop 3 and the through hole 20 after each installation or disassembly and reinstallation, ensuring positioning accuracy.

[0034] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A device for testing the compressive strength of carbonaceous soft rock roadbed structures, characterized in that, It includes a frame (1), a testing workbench (2) mounted on the frame (1), and a pressurizing assembly (12) mounted on the frame (1). The pressurization assembly (12) is used to apply pressure to the cylindrical sample (100) placed on the testing table (2); The testing workbench (2) has a through hole (20), and the inner wall of the through hole (20) is provided with a plurality of convex support blocks (21) arranged in a ring. It also includes a movable platform (22) that moves up and down along the axial direction of the through hole (20), and the bottom side of the movable platform (22) is connected to a drive mechanism that drives its movement; During testing, the columnar sample (100) is retracted into the through hole (20), and its top part protrudes from the upper surface of the testing workbench (2).

2. The compressive strength testing device for carbonaceous soft rock subgrade structures as described in claim 1, characterized in that, The pressurizing assembly (12) includes a pressure block and a pressurizing cylinder that drives the pressure block to move up and down in the vertical direction. A pressure sensor is provided between the output end of the pressurizing cylinder and the pressure block.

3. The compressive strength testing device for carbonaceous soft rock subgrade structures as described in claim 1, characterized in that, The bottom of the through hole (20) extends into the interior of the frame (1). The drive mechanism includes a support plate (111) installed in the frame (1). A lifting cylinder (112) is installed on the upper surface of the support plate (111). The output end of the lifting cylinder (112) is connected to the bottom side of the movable platform (22).

4. The compressive strength testing device for carbonaceous soft rock subgrade structures as described in claim 3, characterized in that, The frame (1) is provided with a mounting cavity (11) communicating with the through hole (20) below, and the support plate (111) is installed in the mounting cavity (11); The upper surfaces of both ends of the support plate (111) are provided with bent portions (113), and the two inner walls of the mounting cavity (11) are provided with support beams (114) supporting the lower surfaces of both ends of the support plate (111). A locking bolt (116) is threaded onto the bent portion (113), and a pin is provided at the end of the locking bolt (116). The inner wall of the mounting cavity (11) is provided with a pin hole for the pin to be inserted.

5. The compressive strength testing device for carbonaceous soft rock subgrade structures as described in claim 4, characterized in that, The upper surface of the support beam (114) is provided with a limiting protrusion (115), and the limiting protrusion (115) is provided with a positioning hole on one side near the support plate (111). The side of the support plate (111) is provided with a positioning post that can be inserted into the positioning hole.

6. The compressive strength testing device for carbonaceous soft rock subgrade structures as described in claim 1, characterized in that, A gap (211) is formed between two adjacent convex support blocks (21), and a support part (221) passing through the gap (211) is provided on the periphery of the movable platform (22).

7. The compressive strength testing device for carbonaceous soft rock subgrade structures as described in claim 1, characterized in that, A positioning mechanism is provided on the upper surface of the detection workbench (2) located at the through hole (20). The positioning mechanism is used to position the columnar sample (100) placed in the through hole (20). The positioning mechanism includes a semi-circular side guard (3) installed on the upper surface of the detection workbench (2). A pair of parallel strip side guards (30) are provided at both ends of the semi-circular side guard (3). A guide part (31) is provided at the end of the strip side guard (30). The semi-circular side guard (3), the strip side guard (30) and the guide part (31) are integrally formed. The two guide parts (31) are in the shape of an "eight", and the semi-circular side guard (3) and the strip side guard (30) are in the shape of a "U". The inner diameter of the semi-circular side guard (3) is larger than the diameter of the through hole (20), and the two are coaxially arranged.

8. The compressive strength testing device for carbonaceous soft rock subgrade structure as described in claim 7, characterized in that, The inner wall surface at the junction of the semi-circular side guard (3) and the strip side guard (30) is provided with a first top rod structure, and the inner wall surface of the semi-circular side guard (3) located between the two first top rod structures is provided with a second top rod structure. The first top rod structure and the second top rod structure have the same structure. The first push rod structure includes a telescopic sleeve rod (34), and the end of the telescopic sleeve rod (34) is provided with a spherical abutment (35) that abuts against the cylindrical sample (100). The telescopic sleeve (34) includes an inner sleeve and an outer sleeve that are sealed together. The inner wall of the outer sleeve is provided with a limiting protrusion to restrict the movement path of the inner sleeve. The upper surface of the semi-circular side guard (3) and / or the strip side guard (30) is provided with a groove, and a telescopic sleeve that extends and retracts in the vertical direction is installed in the groove. The top of the telescopic sleeve is connected to an indicator block, and the telescopic sleeve and the telescopic rod (34) are connected.

9. The compressive strength testing device for carbonaceous soft rock subgrade structure as described in claim 8, characterized in that, The outer wall surface of the semi-circular side guard (3) is provided with mounting ears (32), and mounting bolts (33) pass through the mounting holes of the mounting ears (32). The upper surface of the testing workbench (2) is provided with a threaded hole (24) that is threaded to the mounting bolt (33). An annular groove (23) is provided at the port of the threaded hole (24). An annular positioning boss that is inserted into the annular groove (23) is provided on the mounting ear (32) located on the periphery of the mounting hole.

10. A method for testing the compressive strength of carbonaceous soft rock subgrade structures, characterized in that, It employs a carbonaceous soft rock subgrade structure compressive strength testing device as described in claim 8 or 9 above, specifically including: Step 1: Use a sampling device to collect columnar samples (100) of the active carbonaceous soft rock subgrade. Step 2: Place the columnar sample (100) on the upper surface of the detection worktable (2) and control the movable stage (22) to move upward until its upper surface and the upper surface of the detection worktable (2) are coplanar; Step 3: Control the columnar sample (100) to move to the upper surface of the movable stage (22), and then control the movable stage (22) to slowly move downward to the maximum stroke. At this time, the bottom end of the columnar sample (100) abuts against the convex support block (21). Step 4: Control the pressurization component (12) to move downward to complete the test.

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