Small-sized automatic sounding device capable of being used for measuring strength of fully-weathered layer

Abstract

The invention relates to a small automatic sounding device and method for determining the strength of a fully weathered layer, a motor drives a gear set to control a clamping jaw to grab / release a drop hammer, and automatic free falling hammering is realized; a thin film pressure sensor, a proximity switch and a digital dial indicator are combined to cooperatively monitor the number of hammering times, the hammer falling speed and the penetration depth, and the deformation modulus is calculated in real time through an MCU. The device is portable, solves the problems that traditional equipment is heavy and personal errors exist, and is suitable for rapidly evaluating the strength of the fully-weathered layer of field sites such as slopes and foundation pits.

Description

Technical Field

[0001] The present invention relates to the field of geotechnical engineering detection technology, in particular to a portable automated standard penetration test device for quickly measuring the strength and deformation modulus of soft rock and soil bodies such as fully weathered layers and residual soil. Background Art

[0002] Penetration tests are a common method for evaluating the physical and mechanical properties of soil. They include standard penetration tests, dynamic penetration tests, and static penetration tests, and are widely used in fields such as foundation engineering and earthquake engineering. However, traditional penetration test equipment is bulky and inconvenient to carry and move, which limits its application in complex scenarios such as slopes. Existing small-scale penetration equipment relies on manual control to apply pressure. Inconsistencies in penetration speed and energy can lead to fluctuations in measurement parameters, and test parameter monitoring relies on manual measurement and recording, which is time-consuming and labor-intensive. In addition, moving the device can easily lead to errors in subsequent test data.

[0003] Traditional penetration test equipment is usually bulky, and the inconvenience of carrying and moving it seriously limits its application in complex scenarios such as slopes. Existing small-scale penetration equipment often relies on manual control when applying pressure, which makes the measurement accuracy susceptible to operator influence. For example, inconsistencies in penetration speed and penetration energy may cause fluctuations in key parameters such as the measured penetration strength. In traditional test methods, the monitoring of test parameters relies entirely on manual measurement and recording, which is not only time-consuming but also laborious. Each time the test is restarted after the equipment is moved, the movement of the device may cause errors in the subsequent test data. Therefore, a small-scale automatic penetration device that can be used to measure the strength of the entire weathered layer is proposed. It can easily perform rapid data acquisition and comparative analysis in indoor or field environments to support scientific research and survey and design work. Summary of the Invention

[0004] In order to solve the problems that traditional in-situ penetration devices are large and inconvenient to carry, and that parameter measurement and force application methods during small penetration device tests are easily affected by human factors and lead to errors, the present invention provides a small automatic probing device that can be used to measure the strength of the entire weathering layer, including a placement plane 1 and a penetration monitor body 7. The placement plane 1 is provided with a height adjustment device 5, and the height adjustment device 5 connects the placement plane 1 and the penetration monitor body 7. The penetration monitor body 7 is provided with a free hammer device 3 and a penetration device 2, and the placement plane 1 and the penetration monitor body 7 are both provided with a data monitoring device 4.

[0005] Furthermore, the penetration device 2 includes a drop hammer 200 , a connecting shaft 202 and a penetration head 204 . The drop hammer 200 is slidably mounted above the connecting shaft 202 . Both the drop hammer 200 and the connecting shaft 202 are mounted in the penetration monitor body 7 .

[0006] Furthermore, a first limit plate 201 and a second limit plate 203 are fixedly installed at both ends of the connecting shaft 202, the outer diameter of the first limit plate 201 is slightly smaller than the inner diameter of the penetration monitor body 7, the first limit plate 201 is slidably installed inside the penetration monitor body 7, and the second limit plate 203 is installed outside the penetration monitor body 7. A penetration head 204 is threadedly installed on the end of the connecting shaft 202 near the second limit plate 203.

[0007] Furthermore, the free hammer device 3 includes a first motor 300, a first gear 301, a second gear 302, a threaded rod 303, a connecting block 304, a clamping jaw 305, a spring 309 and a clamping column 312. The first motor 300 is fixedly installed on one side of the penetration monitor body 7, the first gear 301 is fixedly installed on the output shaft of the first motor 300, the first gear (301) is meshed with the second gear (302), the spring 309 is fixedly installed between the two clamping jaws 305, the two clamping jaws 305 are rotationally symmetrically installed on the connecting block 304, the connecting block 304 is fixedly connected to the threaded rod 303, the second gear 302 is threadedly meshed with the threaded rod 303, the clamping column 312 is fixedly installed on the upper surface of the drop hammer 200, and the clamping jaw 305 can clamp / release the clamping column 312.

[0008] Furthermore, the clamping jaw 305 is rotatably mounted on the connecting block 304 via a rotating shaft 308, a clamping head 306 is provided at one end of the clamping jaw 305, and a tail claw 307 is provided at the end of the clamping jaw 305 away from the clamping head 306, and a thin film pressure sensor 311 is fixedly mounted on both the clamping head 306 and the tail claw 307, a conical groove 310 is provided at the top of the penetration monitor body 7, the aperture size above the conical groove 310 is smaller than the aperture size below, and the threaded rod 303 passes through the conical groove 310 and is rotatably mounted in the conical groove 310.

[0009] Furthermore, a dial indicator mounting groove 404 is provided on the penetration monitor body 7, and the digital dial indicator 402 is fixedly installed in the dial indicator mounting groove 404. A measuring rod 403 is provided on the digital dial indicator 402, and the axis of the measuring rod 403 is parallel to the axis of the limiting slide bar 205. One end of the measuring rod 403 is in contact with the lower surface of the first limiting disk 201, and a card cover 405 is clamped in the dial indicator mounting groove 404.

[0010] Furthermore, the data monitoring device 4 includes an industrial control screen 400, an MCU controller 401, a digital dial indicator 402 and a proximity switch 407. The industrial control screen 400 and the MCU controller 401 are fixedly installed on the placement plane 1, and the digital dial indicator 402 and the proximity switch 407 are fixedly installed in the penetration monitor body 7.

[0011] Furthermore, there are two proximity switches 407, which are installed vertically. The industrial control panel 400 is electrically connected to the MCU controller 401, and the MCU controller 401 is electrically connected to the first motor 300, the film pressure sensor 311, the digital dial indicator 402 and the proximity switch 407 respectively.

[0012] Furthermore, the height adjustment device 5 includes a fixing frame 500, which is fixedly mounted on the placement plane 1. A connecting rod 501 is fixedly mounted on the penetration monitor body 7. The other end of the connecting rod 501 is slidably mounted in the fixing frame 500. An adjusting rod 502 is threadedly mounted on one end of the connecting rod 501 close to the fixing frame 500. The adjusting rod 502 passes through the fixing frame 500 and is rotatably mounted in the fixing frame 500. A rotating handle 503 is fixedly mounted on one end of the adjusting rod 502 located outside the fixing frame 500.

[0013] On the other hand, the present invention also provides a method for measuring the strength of the entire weathered layer, based on any of the above-mentioned devices, comprising the steps of: S1, fix the placement plane 1 on the surface of the fully weathered layer, select an appropriate penetration head 204 and install it on the connecting shaft 202, rotate the rotation handle 503 to adjust the height, so that the penetration head 204 contacts the surface of the fully weathered layer and the second limit plate 203 abuts against the bottom end of the penetration monitor body 7; S2, reset the digital dial indicator 402 to zero and set the test parameters through the industrial control screen 400; S3: The first motor 300 drives the first gear 301 and the second gear 302 to rotate, causing the threaded rod 303 to drive the clamping jaw 305 to descend until the chuck 306 clamps the clamping column 312 on the drop hammer 200. After the film pressure sensor 311 on the chuck 306 triggers a pressure signal, the first motor 300 reverses and drives the drop hammer 200 to ascend. S4, when the tail claw 307 enters the tapered groove 310, the clamping jaw 305 rotates to release the clamping column 312 due to the contour of the groove, and the drop hammer 200 freely falls to hit the first limit plate 201, penetrating the entire weathered layer through the connecting shaft 202 and the penetration head 204. At the same time, the thin film pressure sensor 311 on the tail claw 307 triggers a signal, and the MCU controller 401 controls the first motor 300 to pause and then repeat steps S3-S4 to perform multiple tests; S5, calculate the speed by recording the falling time of the drop hammer 200 through two proximity switches 407, obtain the penetration depth through the measuring rod 403 of the digital dial indicator 402, and estimate the equivalent undrained shear strength and deformation modulus based on the number of hammer blows N recorded by the MCU controller 401. The equivalent undrained shear strength τ=0.8437N+67.656, unit kPa, and the deformation modulus E=0.4758N-0.7321, unit MPa, N≥2.

[0014] Advantages:

[0015] (I) the device is placed on the position to be tested by placing a plane, the penetration head is in contact with the surface of the fully weathered layer, the first gear is driven to rotate by the first motor, the second gear is engaged with the first gear, the threaded rod is lifted by the second gear, when the threaded rod is lowered, the clamping jaw can clamp the clamping column on the drop hammer, after the clamping column is clamped, the first motor is reversed to make the threaded rod rise, when the threaded rod rises, the drop hammer rises until the tail claw enters the conical groove, the clamping jaw releases the clamping column to make the drop hammer free fall and hammer the first limiting disc to perform the penetration test, the drop hammer is in free fall by the electric drive, and the test error caused by human factors is avoided.

[0016] (II) when the drop hammer is in free fall, the drop hammer passes through two proximity switches respectively, the distance between the two proximity switches and the signal time received by the two proximity switches are calculated, and then the falling speed of the drop hammer is calculated, when the drop hammer hits the first limiting disc, the first limiting disc and the connecting shaft are pressed down, the first limiting disc is pressed down to trigger the measuring rod, at this time, the numerical value of the displacement of the measuring rod, i.e. the penetration depth, can be read by the digital dial gauge, the number N of times of hammering of the device can be recorded by the MCU controller and the industrial control screen, and the deformation modulus of the fully weathered layer can be estimated by the value N and the penetration depth.

[0017] (III) the suspension height of the penetration monitor body is adjusted by rotating the adjusting rod and the rotating handle, the adjusting rod is lifted and lowered by being engaged with the adjusting rod screw, and the penetration monitor body can be fixed by the fixing frame and the connecting rod during the test, so that the device does not need to be manually held during the test, and the device can remain stable when being hammered. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a three-dimensional structure schematic view of the present application; Figure 2 is a structure schematic view of the height adjusting device of the present application, mainly showing the schematic view of the connecting rod and the adjusting rod; Figure 3 is a structure schematic view of the industrial control screen and the MCU controller of the present application; Figure 4 is a structure schematic view of the first gear and the second gear of the present application; Figure 5 is a structure schematic view of the connecting shaft and the digital dial gauge of the present application; Figure 6 is a structure schematic view of the present application Figure 5 is an enlarged structure schematic view of part A in the present application; Figure 7It is the structural schematic view of the limit slide rod and rear proximity switch structure of the present application. Figure 8 It is the structural schematic view of the drop hammer and connecting shaft structure of the present application. Figure 9 It is the structural schematic view of the spring and clamping jaw structure of the present application. Figure 10 It is the structural schematic view of the measuring rod and first limit disc structure of the present application.

[0019] The figure mark: 1, placement plane; 2, penetration device; 3, free hammering device; 4, data monitoring device; 5, height adjusting device; 7, penetration monitor main body; 200, drop hammer; 201, first limit disc; 202, connecting shaft; 203, second limit disc; 204, penetration head; 205, limit slide rod; 300, first motor; 301, first gear; 302, second gear; 303, threaded rod; 304, connecting block; 305, clamping jaw; 306, chuck; 307, tail claw; 308, rotating shaft; 309, spring; 310, conical groove; 311, thin film pressure sensor; 312, clamping column; 400, industrial control screen; 401, MCU controller; 402, digital dial gauge; 403, measuring rod; 404, dial gauge installation groove; 405, clamping cover; 407, proximity switch; 500, fixing frame; 501, connecting rod; 502, adjusting rod; 503, rotating handle. DETAILED DESCRIPTION

[0020] The specific embodiments of the present application are described in further detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0021] It should be understood that when used in the specification and the appended claims, the term "comprising" indicates the presence of the described features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0022] In order to make the drawing simple, only the parts related to the present application are shown in each drawing, which does not represent the actual structure of the product. In addition, in order to make the drawing simple and easy to understand, in some drawings, only one of the components with the same structure or function is shown, or only one of them is marked. In this paper, "one" not only means "only one", but also means "more than one".

[0023] It should be further understood that the term "and / or" used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0024] In the embodiments shown in the accompanying drawings, directional indications (such as up, down, left, right, front, and rear) used to explain the structure and movement of various components of the present invention are not absolute but relative. These descriptions are applicable when the components are in the positions shown in the accompanying drawings. If the descriptions of the positions of these components are changed, the directional indications will also change accordingly.

[0025] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings and other embodiments can be obtained based on these drawings without inventive work.

[0027] Example 1: Reference Figures 1-10 A small automatic penetration test device for measuring the strength of a fully weathered layer includes a placement plane 1 and a penetration monitor body 7. In order to design a penetration test device suitable for use in indoor laboratories to conduct penetration tests on soft rock samples, a height adjustment device 5 is provided on the placement plane 1, a free hammer device 3 and a penetration device 2 are provided in the placement plane 1, and a data monitoring device 4 is provided in both the placement plane 1 and the penetration monitor body 7. The penetration test on the fully weathered layer is conducted by cooperating with the free hammer device 3 and the penetration device 2. The parameters during the test can be monitored by the data monitoring device 4. The height of the penetration monitor body 7 is adjusted by the height adjustment device 5 and the penetration monitor body 7 is supported. In order to realize the function of penetration test on the whole weathering layer, the penetration device 2 includes a drop hammer 200, a connecting shaft 202 and a penetration head 204. The drop hammer 200 is slidably installed above the connecting shaft 202. The drop hammer 200 and the connecting shaft 202 are both installed in the penetration monitor body 7. The first limit plate 201 and the second limit plate 203 are fixedly installed at both ends of the connecting shaft 202. The outer diameter of the first limit plate 201 is slightly smaller than the inner diameter of the penetration monitor body 7. The first limit plate 201 is slidably installed on the penetration monitor body 7. Inside the main body 7, the second limit plate 203 is installed on the outside of the penetration monitor main body 7, and the connecting shaft 202 is threadedly installed with a penetration head 204 on the side close to the second limit plate 203. A limit slide 205 is fixedly installed in the placement plane 1, and the two ends of the limit slide 205 are respectively fixedly connected to the top and bottom walls of the penetration monitor main body 7. The limit slide 205 passes through the first limit plate 201, the drop hammer 200 and the connecting block 304 and slides with the first limit plate 201, the drop hammer 200 and the connecting block 304.

[0028] In order to realize the function of the hammer penetration device to automatically penetrate the entire weathering layer, the free hammer device 3 includes a first gear 301, a second gear 302, a threaded rod 303, a connecting block 304, a clamping jaw 305, a spring 309 and a clamping column 312. The spring 309 is fixedly installed between the two clamping jaws 305, and the two clamping jaws 305 are rotatably installed on the connecting block 304. The connecting block 304 is fixedly connected to the threaded rod 303, the second gear 302 is threadedly engaged with the threaded rod 303, and the clamping column 312 is fixedly installed on the upper surface of the drop hammer 200. A first motor 300 is fixedly installed on one side of the penetration monitor body 7. The gear 301 is fixedly mounted on the output shaft of the first motor 300, the first motor 300 is meshed with the first gear 301, the clamping jaw 305 is rotatably mounted on the connecting block 304 via the rotating shaft 308, a clamping head 306 is provided at one end of the clamping jaw 305, and a tail claw 307 is provided at the end of the clamping jaw 305 away from the clamping head 306, a thin film pressure sensor 311 is fixedly mounted on the clamping head 306 and the tail claw 307, and a conical groove 310 is opened at the top of the monitor body 7, the aperture size above the conical groove 310 is smaller than the aperture size below, and the threaded rod 303 passes through the conical groove 310 and is rotatably mounted in the conical groove 310.

[0029] When in use, place the device flat on the fully weathered layer to be tested through the placement plane 1, and use a fastening device or adhesive to fix the placement plane on the surface of the fully weathered layer, and select a penetration head 204 of appropriate length and install it on the connecting shaft 202. The length of the penetration head 204 should be greater than the depth to be penetrated during the test.

[0030] The digital dial indicator 402 is reset to zero through the industrial control screen 400, and the test parameters are set on the industrial control screen 400. During the test, the first motor 300 drives the first gear 301 to rotate through the output shaft. When the first gear 301 rotates, it meshes with the second gear 302. When the second gear 302 rotates, it meshes with the threaded rod 303 passing through the center to make it descend. When the threaded rod 303 descends, it drives the clamping claw 305 to descend through the connecting block 304 until the chuck 306 clamps the clamping column 312, and the film pressure sensor 311 on the chuck 306 contacts the drop weight 200 to generate pressure. Then, the first motor 300 starts to reverse. The first motor 300 drives the first gear 301 to reverse through the output shaft, so that the threaded rod 303 drives the connecting block 304 and the drop weight 200 to rise until the tail claw 307 enters the conical groove 310. The tail claw 307 is pressed by the conical groove 310. 0 contour, the clamping jaws 305 will rotate with the rotating shaft 308 as the rotating point, one end of the tail claws 307 will approach each other, and one end of the clamping head 306 will move away from each other. When one end of the clamping head 306 moves away from each other, the clamping column 312 will be loosened. When the clamping column 312 loses the clamping of the clamping jaws 305, the drop hammer 200 will fall freely under gravity until the drop hammer 200 hits the first limit plate 201, applying pressure to the first limit plate 201, the connecting shaft 202 and the penetration head 204 to perform a penetration test. At the same time, when the film pressure sensor 311 on the tail claw 307 is squeezed by the contour of the tapered groove 310 to generate pressure, the film pressure sensor 311 transmits a signal to the MCU controller 401, and the MCU controller 401 controls the first motor 300 to stop working again. Then the first motor 300 repeats the above operation of lowering the clamping jaws 305 and starts the second penetration test.

[0031] Example 2: Reference Figure 1-4 In order to realize the function of monitoring test parameters, the data monitoring device 4 includes an industrial control screen 400, an MCU controller 401, a digital dial indicator 402, and a proximity switch 407. The industrial control screen 400 and the MCU controller 401 are fixedly mounted on the placement plane 1, the digital dial indicator 402 and the proximity switch 407 are fixedly mounted in the penetration monitor body 7, the penetration monitor body 7 is provided with a dial indicator mounting groove 404, the digital dial indicator 402 is fixedly mounted in the dial indicator mounting groove 404, a measuring rod 403 is provided on the digital dial indicator 402, the axis of the measuring rod 403 is parallel to the axis of the limit slide 205, one end of the measuring rod 403 is in contact with the lower surface of the first limit disk 201, a card cover 405 is clamped in the dial indicator mounting groove 404, a groove is provided on the placement plane 1, there are two proximity switches 407, and the two proximity switches 407 are installed vertically.

[0032] In order to realize the functions of electrical control and communication of electrical components, the industrial control panel 400 is electrically connected to the MCU controller 401 , and the MCU controller 401 is electrically connected to the first motor 300 , the film pressure sensor 311 , the digital dial indicator 402 , and the proximity switch 407 .

[0033] When the drop hammer 200 is in free fall, it will pass through two proximity switches 407 respectively. The outline size of the drop hammer 200 is larger than the first limit plate 201, so the proximity switch 407 will only sense the movement of the drop hammer 200, and the first limit plate 201 will not be detected by the proximity switch 407. By calculating the time difference between the two proximity switches 407 receiving signals and the installation distance between the two proximity switches 407, the falling speed of the drop hammer 200 can be calculated.

[0034] When the drop hammer 200 hits the first limiting plate 201 , the force of the drop hammer 200 will be transmitted to the entire weathered layer through the first limiting plate 201 , the connecting shaft 202 and the penetration head 204 .

[0035] When the drop hammer 200 hits the first limit plate 201, if the penetration head 204 enters the fully weathered layer, the first limit plate 201 will move downward. When the first limit plate 201 moves downward, it will trigger the measuring rod 403 to move. The dial indicator mounting slot 404 can read the distance moved by the measuring rod 403, so that the penetration depth can be obtained. The signal values ​​of the two thin film pressure sensors 311 are recorded by the MCU controller 401. When the two thin film pressure sensors 311 are triggered once, an electrical signal is recorded as the number N of hammer strikes. The strength, deformation modulus and other parameters of the fully weathered layer can be estimated through the N value and the penetration depth. The remaining features are the same as those in Example 1.

[0036] Example 3: Reference Figure 1-Figure 2 In order to realize the function of fixing and adjusting the height of the penetration monitor body 7, the height adjustment device 5 includes a fixing frame 500, which is fixedly installed on the placement plane 1. A connecting rod 501 is fixedly installed on the penetration monitor body 7, and the other end of the connecting rod 501 is slidably installed in the fixing frame 500. An adjusting rod 502 is threadedly installed on one end of the connecting rod 501 close to the fixing frame 500. The adjusting rod 502 passes through the fixing frame 500 and is rotatably installed in the fixing frame 500. A rotating handle 503 is fixedly installed on one end of the adjusting rod 502 located outside the fixing frame 500.

[0037] By manually rotating the rotating handle 503, the rotating handle 503 is driven to rise and fall through the threaded engagement of the adjusting rod 502 and the connecting rod 501. By controlling the rotation direction of the rotating handle 503, the penetration head 204 on the penetration monitor body 7 is brought into contact with the surface of the fully weathered layer, and the second limit plate 203 is abutted against the bottom end of the penetration monitor body 7. At this time, the debugging is completed. During the test, there is no need to manually hold the device, so that it can remain stable when subjected to hammering force. The remaining features are the same as those in Example 1.

[0038] Working principle: When in use, place the device flat on the fully weathered layer to be tested through the placement plane 1, and use a fastening device or adhesive to fix the placement plane on the surface of the fully weathered layer, and select a penetration head 204 of appropriate length and install it on the connecting shaft 202. The length of the penetration head 204 should be greater than the depth to be penetrated during the test. By manually rotating the rotating handle 503, the rotating handle 503 is driven to rise and fall through the threaded engagement of the adjusting rod 502 and the connecting rod 501 when it is rotated. By controlling the rotation direction of the rotating handle 503, the penetration head 204 on the penetration monitor body 7 is in contact with the surface of the fully weathered layer, and the second limit plate 203 is against the bottom end of the penetration monitor body 7. At this time, the debugging is completed, and the digital dial indicator 40 is set through the industrial control screen 400. 2 value is reset to zero, and the test parameters are set on the industrial control screen 400. During the test, the first motor 300 drives the first gear 301 to rotate through the output shaft. When the first gear 301 rotates, it meshes with the second gear 302. When the second gear 302 rotates, it meshes with the threaded rod 303 passing through the center to make it descend. When the threaded rod 303 descends, it drives the clamping claw 305 to descend through the connecting block 304 until the chuck 306 clamps the clamping column 312 and the film pressure sensor 311 on the chuck 306 contacts the drop weight 200 to generate pressure. Then, the first motor 300 starts to reverse. The first motor 300 drives the first gear 301 to reverse through the output shaft, so that the threaded rod 303 drives the connecting block 304 and the drop weight 200 to rise until the tail claw 3 When the chuck 306 moves away from the chuck 306, the clamping column 312 is released. When the clamping column 312 loses the grip of the clamping claw 305, the drop hammer 200 falls freely under gravity until the drop hammer 200 hits the first limit plate 201, applies pressure to the first limit plate 201, the connecting shaft 202 and the penetration head 204 to perform a penetration test. At the same time, when the thin film pressure sensor 311 on the tail claw 307 is squeezed by the contour of the conical groove 310 and generates pressure, the thin film pressure sensor 311 transmits the signal to the MCU for control. On the device 401, the MCU controller 401 controls the first motor 300 to stop working again, and then the first motor 300 repeats the above-mentioned operation of lowering the clamping claw 305 to start the second penetration test. When the drop hammer 200 falls freely, the drop hammer 200 will pass through two proximity switches 407 respectively. The outline size of the drop hammer 200 is larger than the first limit plate 201, so the proximity switch 407 will only sense the movement of the drop hammer 200, and the first limit plate 201 will not be detected by the proximity switch 407. By calculating the time difference between the two proximity switches 407 receiving the signals and the installation distance between the two proximity switches 407, the falling speed of the drop hammer 200 can be calculated. When the drop hammer 200 hits the first limit plate 201,The force of the hammer 200 will be transmitted to the fully weathered layer through the first limit plate 201, the connecting shaft 202 and the penetration head 204. When the hammer 200 hits the first limit plate 201, if the penetration head 204 enters the fully weathered layer, the first limit plate 201 will move downward. When the first limit plate 201 moves downward, it will trigger the measuring rod 403 to move. The dial indicator mounting slot 404 can read the distance the measuring rod 403 moves, so that the penetration depth can be obtained. The MCU controller 401 records the signal values ​​of the two film pressure sensors 311. When the two film pressure sensors 311 are each triggered by an electrical signal, it is recorded as the number of hammer strikes N. The equivalent undrained shear strength and deformation modulus can be estimated based on the N value and the penetration depth. The equivalent undrained shear strength τ = 0.8437N + 67.656, in kPa, and the deformation modulus E = 0.4758N - 0.7321, in MPa, where N ≥ 2.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A small automatic penetration device for measuring the strength of the entire weathered layer, characterized in that: The invention comprises a placement plane (1) and a penetration monitor body (7), wherein a height adjustment device (5) is provided on the placement plane (1), and the height adjustment device (5) connects the placement plane (1) and the penetration monitor body (7), wherein a free hammer device (3) and a penetration device (2) are provided in the penetration monitor body (7), and a data monitoring device (4) is provided in both the placement plane (1) and the penetration monitor body (7).

2. The small automatic contact probe device according to claim 1, characterized in that: The penetration device (2) comprises a drop hammer (200), a connecting shaft (202) and a penetration head (204); the drop hammer (200) is slidably mounted above the connecting shaft (202); and the drop hammer (200) and the connecting shaft (202) are both mounted in a penetration monitor body (7).

3. The small automatic contact probe device according to claim 2, characterized in that: A first limiting plate (201) and a second limiting plate (203) are fixedly mounted on both ends of the connecting shaft (202), respectively. The outer diameter of the first limiting plate (201) is slightly smaller than the inner diameter of the penetration monitor body (7). The first limiting plate (201) is slidably mounted inside the penetration monitor body (7), and the second limiting plate (203) is mounted outside the penetration monitor body (7). A penetration head (204) is threadedly mounted on one side of the end of the connecting shaft (202) close to the second limiting plate (203).

4. The small automatic probe device according to claim 1, characterized in that: The free hammer device (3) comprises a first motor (300), a first gear (301), a second gear (302), a threaded rod (303), a connecting block (304), a clamping claw (305), a spring (309) and a clamping column (312), wherein the first motor (300) is fixedly mounted on one side of the penetration monitor body (7), the first gear (301) is fixedly mounted on the output shaft of the first motor (300), the first gear (301) is meshed with the second gear (302), the spring (309) is fixedly mounted between two clamping claws (305), the two clamping claws (305) are rotationally symmetrically mounted on the connecting block (304), the connecting block (304) is fixedly connected to the threaded rod (303), the second gear (302) is threadedly meshed with the threaded rod (303), the clamping column (312) is fixedly mounted on the upper surface of the drop hammer (200), and the clamping claw (305) can clamp / release the clamping column (312).

5. The small automatic probe device according to claim 4, characterized in that: The clamping jaw (305) is rotatably mounted on the connecting block (304) via a rotating shaft (308); a clamping head (306) is provided at one end of the clamping jaw (305); a tail claw (307) is provided at one end of the clamping jaw (305) away from the clamping head (306); a thin film pressure sensor (311) is fixedly mounted on both the clamping head (306) and the tail claw (307); a conical groove (310) is formed on the top of the penetration monitor body (7); the aperture size of the upper portion of the conical groove (310) is smaller than the aperture size of the lower portion; the threaded rod (303) passes through the conical groove (310) and is rotatably mounted in the conical groove (310).

6. The small automatic probe device according to claim 1, characterized in that: A dial indicator mounting groove (404) is provided on the penetration monitor body (7), the digital dial indicator (402) is fixedly mounted in the dial indicator mounting groove (404), a measuring rod (403) is provided on the digital dial indicator (402), the axis of the measuring rod (403) is parallel to the axis of the limiting slide rod (205), one end of the measuring rod (403) is in contact with the lower surface of the first limiting disk (201), and a card cover (405) is clamped in the dial indicator mounting groove (404).

7. The small automatic contact probe device according to claim 6, characterized in that: The data monitoring device (4) includes an industrial control screen (400), an MCU controller (401), a digital dial indicator (402) and a proximity switch (407). The industrial control screen (400) and the MCU controller (401) are both fixedly mounted on a placement plane (1), and the digital dial indicator (402) and the proximity switch (407) are both fixedly mounted in a penetration monitor body (7).

8. The small automatic contact probe device according to claim 7, characterized in that: There are two proximity switches (407), which are vertically mounted. The industrial control panel (400) is electrically connected to the MCU controller (401), and the MCU controller (401) is electrically connected to the first motor (300), the film pressure sensor (311), the digital dial indicator (402), and the proximity switch (407).

9. The small automatic contact probe device according to claim 1, characterized in that: The height adjustment device (5) includes a fixing frame (500), the fixing frame (500) is fixedly mounted on the placement plane (1), a connecting rod (501) is fixedly mounted on the penetration monitor body (7), the other end of the connecting rod (501) is slidably mounted in the fixing frame (500), an adjusting rod (502) is threadedly mounted on one end of the connecting rod (501) close to the fixing frame (500), the adjusting rod (502) passes through the fixing frame (500) and is rotatably mounted in the fixing frame (500), and a rotating handle (503) is fixedly mounted on one end of the adjusting rod (502) located outside the fixing frame (500).

10. A method for measuring the strength of a fully weathered layer, based on the apparatus of any one of claims 1 to 9, comprising the steps of: S1, fix the placement plane (1) on the surface of the fully weathered layer, select an appropriate penetration head (204) and install it on the connecting shaft (202), rotate the rotation handle (503) to adjust the height, so that the penetration head (204) contacts the surface of the fully weathered layer and the second limit plate (203) abuts against the bottom end of the penetration monitor body (7); S2, reset the digital dial indicator (402) to zero and set the test parameters through the industrial control screen (400); S3, the first motor (300) drives the first gear (301) and the second gear (302) to rotate, so that the threaded rod (303) drives the clamping claw (305) to descend until the clamping head (306) clamps the clamping column (312) on the drop hammer (200), and after the film pressure sensor (311) on the clamping head (306) triggers a pressure signal, the first motor (300) reverses to drive the drop hammer (200) to ascend; S4, when the tail claw (307) enters the conical groove (310), the clamping claw (305) rotates to release the clamping column (312) under the action of its contour, and the drop hammer (200) freely falls to hit the first limit plate (201), and penetrates the entire weathered layer through the connecting shaft (202) and the penetration head (204). At the same time, the film pressure sensor (311) on the tail claw (307) triggers a signal, and the MCU controller (401) controls the first motor (300) to pause and then repeat steps S3-S4 to perform multiple tests; S5, the falling time of the drop hammer (200) is recorded by two proximity switches (407) to calculate the speed, the penetration depth is obtained by the measuring rod (403) of the digital dial indicator (402), and the equivalent undrained shear strength and deformation modulus are estimated in combination with the number of hammer blows N recorded by the MCU controller (401). The equivalent undrained shear strength τ=0.8437N+67.656, unit kPa, and the deformation modulus E=0.4758N-0.7321, unit MPa, N≥2.

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