A subgrade pavement modal tester

Abstract

The application discloses a kind of roadbed pavement modal testers, comprising: test frame, test frame bottom is detachably connected with coupling base;Test rod, one end of test rod is fixedly connected with hammer ball;Positioning mechanism, positioning mechanism is installed at the top of test frame, test rod is vertically inserted in test frame, and test rod is limited with positioning mechanism cooperation;Height measurement module, height measurement module is installed at the bottom of positioning mechanism;Monitoring module, monitoring module is installed at the bottom of test frame;Controller, controller is installed on test frame, height measurement module is connected with controller, display is installed on test frame, and display is connected with controller;Scale line is provided on test rod.The application combines traditional impact test with intelligent monitoring, realizes the rapid, accurate, on-site detection of roadbed pavement modal characteristics and hammer ball rebound height, enriches road construction detection technology, and significantly improves road detection efficiency and reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of road engineering, in particular to a roadbed pavement modal tester. BACKGROUND

[0002] In the process of roadbed pavement rolling construction, the monitoring work of compaction quality needs to be carried out continuously. For soil roadbed and the base layer and subbase layer of pavement, the commonly used compaction quality detection means is mainly the compaction degree index test, but this index is difficult to reflect the rationality of the compaction process of the road roller (such as whether the vibration frequency of the vibration road roller is appropriate) in real time, so as to provide technical reference for the optimization of the compaction process, and it is also difficult to meet the requirements of intelligent compaction. For the stone-filled roadbed, the method of elevation detection is often used to detect the compaction quality in engineering practice, that is, by comparing the elevation change of the test point before and after rolling, it is judged whether the stone-filled roadbed reaches a stable compaction state, specifically, if the change of the elevation of the test point after rolling is within the required standard range, it means that the compaction of the stone-filled roadbed tends to be stable, and the compaction can be stopped; but this detection method has obvious disadvantages, the required instrument equipment and human resources cost is high, and the detection efficiency is low, which is difficult to meet the requirements of large-scale and high-efficiency construction detection. Therefore, it is urgent to develop innovative solutions to improve the efficiency of the existing test method.

[0003] Based on the above technical problems, the present application provides a roadbed pavement modal tester, which can not only test the modal of the earthwork roadbed and the pavement base layer and subbase layer in the construction process, but also test the compaction stability of the stone-filled roadbed; the former is very suitable for the needs of intelligent compaction, and the latter has the characteristics of efficient, convenient and economical. SUMMARY

[0004] The purpose of the present application is to provide a roadbed pavement modal tester to solve the problems existing in the prior art.

[0005] To achieve the above-mentioned purpose, the present application provides the following scheme: the present application provides a roadbed pavement modal tester, comprising:

[0006] A test frame, the bottom of the test frame is detachably connected with a coupling base;

[0007] A test rod, one end of the test rod is fixedly connected with a hammer ball;

[0008] A positioning mechanism, the positioning mechanism is installed at the top end of the test frame, the test rod is vertically inserted into the test frame, and the test rod is limitedly matched with the positioning mechanism;

[0009] A height measuring module, the height measuring module is installed at the bottom of the positioning mechanism, and the height measuring module is correspondingly arranged between the height measuring module and the hammer ball, for detecting the rebound height of the hammer ball;

[0010] A monitoring module is installed at the bottom of the test frame and used to monitor the impact force of the hammer ball impacting the coupling base and the speed and acceleration signals of the subgrade pavement vibration;

[0011] A controller is installed on the test frame, the height measuring module is connected to the controller, the monitoring module is connected to a notebook computer, a display is installed on the test frame and connected to the controller.

[0012] The test rod is provided with a scale line.

[0013] The test frame comprises a top plate and a bottom plate, the top plate is of a ring structure, a plurality of groups of support rods are arranged between the top plate and the bottom plate, the support rods are arranged at equal intervals in the circumferential direction of the top plate, the bottom of the bottom plate is fixedly connected with a protruding block, the protruding block is detachably connected with the coupling base, a plurality of installation grooves are formed in the protruding block, and the monitoring module is installed in the installation grooves.

[0014] The positioning mechanism comprises a plurality of sliding blocks, a plurality of sliding grooves are formed in the top plate at axial intervals, the plurality of sliding grooves are arranged in one-to-one correspondence with the plurality of positioning mechanisms, the axis of the sliding groove is perpendicular to the axis of the top plate, the sliding block is slidably connected in the sliding groove, the top of the sliding block is fixedly connected with a sliding plate, the sliding plate is slidably connected to the top surface of the top plate, a clamping plate is slidably connected to the top surface of the sliding plate, the clamping plate is of an L-shaped structure, the clamping plate abuts against the test rod, a first elastic compression assembly is installed between the sliding plate and the clamping plate, a placing groove is formed in the sliding groove, a second elastic compression assembly is installed in the placing groove, the sliding block is fixed to the second elastic compression assembly, a control assembly is installed on the bottom surface of the top plate, and the sliding block slides on the control assembly.

[0015] The first elastic compression assembly comprises a fixed block, a through groove is formed in the clamping plate, a horizontal groove is formed in the side wall of the through groove, a pressing block is slidably connected in the horizontal groove, the fixed block is fixedly connected to the top surface of the sliding plate and slidably connected in the through groove, the pressing block is fixed to the side surface of the fixed block, a first spring is placed in the horizontal groove, one end of the first spring is fixed to the side surface of the horizontal groove, and the other end is fixedly connected to the pressing block.

[0016] According to the roadbed pavement modal testing apparatus provided by the application, the second elastic compression assembly comprises a second spring, one end of the second spring is fixed at the bottom of the placing groove, the other end of the second spring is fixed at the side of the sliding block, a telescopic rod is fixedly connected between the sliding block and the bottom wall of the placing groove, and the second spring is sleeved on the telescopic rod.

[0017] According to the roadbed pavement modal testing apparatus provided by the application, the control assembly comprises a gasket plate rotationally connected to the bottom surface of the top plate, the gasket plate is in an annular structure, a plurality of groups of straight grooves are equidistantly arranged on the top surface of the gasket plate in the circumferential direction, the straight grooves are arranged perpendicularly to the axis of the gasket plate, a plurality of sliding blocks are arranged correspondingly to the straight grooves, a connecting groove is arranged between adjacent straight grooves and is in communication with one end of the two straight grooves away from each other, the straight grooves are arranged in an inner spiral structure, the sliding blocks are in sliding fit with the straight grooves and the connecting grooves, the outer wall of the gasket plate is provided with a gear slot, and a worm is rotationally connected to the bottom surface of the top plate through a mounting seat and is in mesh with the gear slot.

[0018] According to the roadbed pavement modal testing apparatus provided by the application, the height measuring module comprises a laser range finder, and the laser range finder is fixedly arranged perpendicularly to the bottom surface of the gasket plate.

[0019] According to the roadbed pavement modal testing apparatus provided by the application, the monitoring module comprises a force sensor, an acceleration sensor and a speed sensor, and the force sensor, the acceleration sensor and the speed sensor are arranged in the mounting groove respectively.

[0020] The application discloses the following technical effects:

[0021] 1) The detachable coupling base and the modular design facilitate transportation and rapid installation, and adapt to the on-site testing requirements of different roadbeds (earth roadbeds, rock-filled roadbeds) and pavement base layers and subbase layers in the compaction process.

[0022] 2) The controller automatically processes data, reduces human error, the display real-time feedback result realizes "one-key" operation and reduces professional threshold.

[0023] 3) The scale line and the positioning mechanism ensure that the hammer ball height is adjustable and the falling track is vertical, ensure that the test conditions are consistent multiple times, and the data comparability is strong.

[0024] 4) The modal analysis is used to evaluate the modal characteristics of the earth roadbed and the pavement base layer and the subbase layer in the compaction process, provide technical support for intelligent compaction or vibration compaction process optimization, and provide a scientific basis for high-quality compaction decision-making.

[0025] 5) Through the determination of rebound height of hammer ball, the stability of the filled rock roadbed compaction is quickly judged, that is, when the rebound height of the same measuring point before and after compaction is within the allowable standard range, it is considered that the stable compaction state is reached, thereby providing a new technical support for the filled rock roadbed compaction quality detection. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0027] Figure 1 Fig. 1 is a structural schematic diagram of the roadbed pavement modal tester of the present application;

[0028] Figure 2 Fig. 2 is an enlarged view of position A in Fig. 1; Figure 1

[0029] Figure 3 Fig. 3 is a structural schematic diagram of the cushion plate of the present application.

[0030] In the present application, 1 is a coupling base, 2 is a test rod, 3 is a hammer ball, 4 is a display, 5 is a top plate, 6 is a bottom plate, 7 is a support rod, 8 is a protruding block, 9 is a sliding groove, 10 is a sliding block, 11 is a sliding plate, 12 is a clamping plate, 13 is a placing groove, 14 is a fixing block, 15 is a through groove, 16 is a horizontal groove, 17 is an extrusion block, 18 is a first spring, 19 is a second spring, 20 is a cushion plate, 21 is a straight groove, 22 is a connecting groove, 23 is a worm, and 24 is a laser range finder. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0032] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0033] With reference to Figures 1-3 , the present application provides a roadbed pavement modal tester, which comprises:

[0034] A test stand, the bottom of the test stand is detachably connected with a coupling base 1;

[0035] ​The test rod 2 is fixedly connected with a hammer ball 3 at one end;

[0036] A positioning mechanism is installed at the top end of the test stand, the test rod 2 is vertically inserted into the test stand, and the test rod 2 is limitedly matched with the positioning mechanism;

[0037] A height measuring module is installed at the bottom of the positioning mechanism, and the height measuring module is correspondingly arranged between the hammer ball 3, and is used for detecting the height change of the hammer ball 3;

[0038] A monitoring module is installed at the bottom of the test stand, and is used for monitoring the impact force of the hammer ball 3 hammering the coupling base 1 and the speed and acceleration signal of the vibration of the roadbed and pavement;

[0039] A controller is installed on the test stand, the height measuring module and the monitoring module are connected with the controller, a display 4 is installed on the test stand, and the display 4 is connected with the controller;

[0040] The test rod 2 is provided with a scale line.

[0041] When the test stand is fixed on the roadbed or pavement to be tested through the coupling base 1 at the bottom, the stability of the test stand is ensured, and the test stand is in close contact with the test surface, so that external interference is reduced. The test rod 2 is vertically inserted into the test stand, the hammer ball 3 at the bottom end of the test rod 2 keeps a certain initial height (adjusted through the scale line) from the roadbed or pavement base layer and bottom base layer, and the position is locked through the positioning mechanism, so that the hammer ball 3 vertically falls. The test rod 2 is released, the hammer ball 3 freely falls and hits the roadbed or pavement base layer and bottom base layer, and excitation vibration is generated. The height measuring module monitors the height change of the hammer ball 3 in the falling process and the rebounding process in real time, simultaneously forms a change curve, and intercepts the peak value of the first rebound as a reference. The monitoring module synchronously records the impact force of the hammer ball 3 hammering the coupling base and the speed and acceleration signal of the vibration of the roadbed or pavement base layer and bottom base layer, and inputs the controller, analyzes and analyzes through the corresponding software system, and finally obtains the test data such as frequency and amplitude. Combined with the impact force and rebound height and other information, the modal characteristics (natural frequency, damping ratio and the like) of the roadbed and pavement and the stiffness characteristics of the stone-filled roadbed are calculated by the controller. The results are directly displayed on the display 4, which is used for optimization decision of the compaction process and judgment of the compaction quality.

[0042] Further optimization scheme, the test stand includes a top plate 5 and a bottom plate 6, the top plate 5 is a ring structure, a plurality of groups of support rods 7 are arranged between the top plate 5 and the bottom plate 6, the support rods 7 are arranged at equal intervals around the top plate 5 in the circumferential direction, the bottom plate 6 is fixedly connected with a lug 8 at the bottom, the lug 8 is detachably connected with the coupling base 1, a plurality of installation grooves are formed in the lug 8, and the monitoring module is installed in the installation grooves.

[0043] Further optimization scheme, the positioning mechanism is provided with a plurality of groups around the axis of the top plate 5 at equal intervals, the positioning mechanism includes a plurality of sliding blocks 10, the top plate 5 is provided with a plurality of sliding grooves 9 at equal intervals in the axial direction, the plurality of sliding grooves 9 are correspondingly arranged with the plurality of positioning mechanisms respectively, the axis of the sliding groove 9 is perpendicular to the axis of the top plate 5, the sliding groove 9 is slidably connected with the sliding block 10 respectively, the top of the sliding block 10 is fixedly connected with a sliding plate 11, the sliding plate 11 is slidably connected to the top surface of the top plate 5, the top surface of the sliding plate 11 is slidably connected with a clamping plate 12, the clamping plate 12 is of L-shaped structure, the clamping plate 12 abuts between the test rod 2, the first elastic compression assembly is installed between the sliding plate 11 and the clamping plate 12, the sliding groove 9 is provided with a placing groove 13, the second elastic compression assembly is installed in the placing groove 13, the sliding block 10 is fixed with the second elastic compression assembly, the bottom surface of the top plate 5 is installed with a control assembly, and the sliding block 10 slides on the control assembly.

[0044] Further optimization scheme, the first elastic compression assembly includes a fixed block 14, the clamping plate 12 is provided with a through groove 15, the side wall of the through groove 15 is provided with a horizontal groove 16, the horizontal groove 16 is slidably connected with a pressing block 17, the fixed block 14 is fixedly connected to the top surface of the sliding plate 11, and the fixed block 14 is slidably connected in the through groove 15, the pressing block 17 is fixed to the side surface of the fixed block 14, the first spring 18 is placed in the horizontal groove 16, one end of the first spring 18 is fixed to the side surface of the horizontal groove 16, and the other end is fixedly connected with the pressing block 17.

[0045] Further optimization scheme, the second elastic compression assembly includes a second spring 19, one end of the second spring 19 is fixed to the bottom of the placing groove 13, the other end of the second spring 19 is fixed to the side surface of the sliding block 10, the sliding block 10 and the bottom wall of the placing groove 13 are fixedly connected with a telescopic rod, and the second spring 19 is sleeved on the telescopic rod.

[0046] Further optimization scheme, the control assembly includes a pad 20 rotatably connected to the bottom surface of the top plate 5, the pad 20 is of annular structure, a plurality of straight grooves 21 are circumferentially and equally spaced on the top surface of the pad 20, the straight grooves 21 are arranged perpendicular to the axis of the pad 20, a plurality of sliding blocks 10 are correspondingly arranged with a plurality of straight grooves 21, a connecting groove 22 is arranged between adjacent straight grooves 21, and the connecting groove 22 is communicated with the ends of the two straight grooves 21 away from each other, the straight grooves 21 are arranged in an inner spiral structure, the sliding block 10 is slidably connected with the straight grooves 21 and the connecting groove 22, the outer wall of the pad 20 is provided with a gear slot, the bottom surface of the top plate 5 is rotatably connected with a worm 23 through a mounting seat, and the worm 23 is engaged with the gear slot.

[0047] The coupling base 1 is in contact with the roadbed / pavement base layer and the bottom base layer, and is detachably connected through the protrusions 8 at the bottom of the bottom plate 6, so as to ensure the stability of the test frame.

[0048] The monitoring module is embedded in the installation groove and directly contacts the roadbed or pavement base layer and the bottom base layer to collect signals such as hammering force and vibration response in real time.

[0049] The worm 23 rotates to drive the pad plate 20 to rotate, and the linear groove 21 (internal spiral) on the pad plate 20 pushes the slider 10 to move radially along the sliding groove 9, so as to realize synchronous tightening or loosening of multiple sets of clamping plates 12.

[0050] The clamping plate 12 is adaptively clamped to the test rod 2 by the first elastic compression assembly (extrusion block 17 + first spring 18).

[0051] The second elastic compression assembly (telescopic rod + second spring 19) buffers the movement of the slider 10 and enhances the positioning stability.

[0052] After the test rod 2 is released, the hammer ball 3 freely falls and hits the road surface to generate exciting vibration.

[0053] The height measuring module records the initial height and rebound height change of the hammer ball 3, and the maximum rebound height after different compaction times indicates that the stone-filled roadbed compaction reaches a stable state.

[0054] The vibration response of the roadbed or road base layer is transmitted to the controller through the monitoring module, and the modal parameters (frequency, damping ratio, etc.) are analyzed.

[0055] The height of the test rod 2 is adjusted by the scale line to ensure that the initial release position of the hammer ball 3 is the same in multiple tests, that is, the impact energy is the same each time; the positioning mechanism can be quickly reset to realize continuous multiple tests.

[0056] Multiple synchronous sliders 10 + internal spiral groove design: the worm 23 drives the pad plate 20 to rotate, realizing the synchronous radial movement of all clamping plates 12, ensuring that the test rod 2 is always vertically centered, and avoiding eccentric impact errors.

[0057] The first elastic compression assembly (horizontal spring + extrusion block 17) flexibly clamps the test rod 2, reducing frictional interference when released.

[0058] The second elastic compression assembly (telescopic rod + sleeve spring) stabilizes the movement of the slider 10 and prevents loose positioning.

[0059] Worm 23 - gear slot transmission: only need to rotate the worm 23 to control all clamping plates 12, which is simple and consistent in positioning, suitable for rapid and repeated testing.

[0060] Modular monitoring unit: the monitoring module in the installation groove can be flexibly configured to adapt to the expansion needs of different parameters (such as strain and stress).

[0061] Annular top plate 5 + circumferential support rod 7: evenly distribute the load to improve the impact resistance of the test stand.

[0062] L-shaped clamping plate 12 + through groove 15 design: increases the clamping contact surface to prevent the test rod 2 from slipping or deflecting.

[0063] Detachable coupling base 1: adaptable to different road base and subbase types and uneven sites.

[0064] The solution is further optimized so that the height measurement module includes a laser rangefinder 24, which is vertically fixed to the bottom surface of the pad 20.

[0065] The scheme has been further optimized. The monitoring module includes a force sensor, a velocity sensor, and an acceleration sensor, which are installed in the mounting slots respectively.

[0066] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0067] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A roadbed and pavement modal testing instrument, characterized in that, include: Test fixture, the bottom of which is detachably connected to a coupling base (1); Test rod (2), one end of which is fixedly connected to a hammer ball (3); A positioning mechanism is installed at the top of the test frame, and the test rod (2) is vertically inserted into the test frame, and the test rod (2) is limited to the positioning mechanism. A height measurement module is installed at the bottom of the positioning mechanism and is correspondingly set between the height measurement module and the hammer ball (3) to detect the height of the hammer ball (3) after it bounces off the coupling base; The monitoring module is installed at the bottom of the test frame and is used to monitor the impact force of the hammer ball (3) striking the coupling base (1) and the speed and acceleration signals of the roadbed and pavement vibration. The controller is mounted on the test frame. The height measurement module and the monitoring module are both connected to the controller. A display (4) is mounted on the test frame and is connected to the controller. The test rod (2) is provided with scale lines; The test frame includes a top plate (5) and a bottom plate (6). Several sets of positioning mechanisms are evenly spaced around the axis of the top plate (5). Each positioning mechanism includes several sliders (10). Several grooves (9) are axially spaced on the top plate (5). Each groove (9) corresponds to one of the positioning mechanisms. The axis of each groove (9) is perpendicular to the axis of the top plate (5). Each slider (10) is slidably connected within a groove (9). A sliding plate (11) is fixedly connected to the top of each slider (10). The sliding plate (11) is slidably connected to the bottom plate. The top surface of the top plate (5) is slidably connected to the top surface of the slide plate (11) with a clamping plate (12). The clamping plate (12) has an L-shaped structure and abuts against the test rod (2). A first elastic compression component is installed between the slide plate (11) and the clamping plate (12). A placement groove (13) is opened in the slide groove (9). A second elastic compression component is installed in the placement groove (13). The slider (10) is fixed to the second elastic compression component. A control component is installed on the bottom surface of the top plate (5). The slider (10) slides on the control component.

2. The roadbed and pavement modal testing instrument according to claim 1, characterized in that: The top plate (5) is a ring structure. Several sets of support rods (7) are provided between the top plate (5) and the bottom plate (6). The support rods (7) are arranged at equal intervals around the top plate (5). A protrusion (8) is fixedly connected to the bottom of the bottom plate (6). The protrusion (8) is detachably connected to the coupling base (1). Several mounting slots are provided on the protrusion (8). The monitoring modules are installed in the mounting slots respectively.

3. The roadbed and pavement modal testing instrument according to claim 1, characterized in that: The first elastic compression assembly includes a fixing block (14), a through groove (15) is provided on the clamping plate (12), a horizontal groove (16) is provided on the side wall of the through groove (15), a squeezing block (17) is slidably connected in the horizontal groove (16), the fixing block (14) is fixedly connected to the top surface of the sliding plate (11), and the fixing block (14) is slidably connected in the through groove (15), the squeezing block (17) is fixed to the side of the fixing block (14), and a first spring (18) is placed in the horizontal groove (16). One end of the first spring (18) is fixed to the side of the horizontal groove (16), and the other end is fixedly connected to the squeezing block (17).

4. The roadbed and pavement modal testing instrument according to claim 1, characterized in that: The second elastic compression assembly includes a second spring (19), one end of which is fixed to the bottom of the placement groove (13), and the other end of which is fixed to the side of the slider (10). A telescopic rod is fixedly connected between the slider (10) and the bottom wall of the placement groove (13), and the second spring (19) is sleeved on the telescopic rod.

5. A roadbed and pavement modal testing instrument according to claim 1, characterized in that: The control component includes a pad (20) rotatably connected to the bottom surface of the top plate (5). The pad (20) has an annular structure. The top surface of the pad (20) is provided with several sets of straight grooves (21) at equal intervals around the periphery. The straight grooves (21) are perpendicular to the axis of the pad (20). Several sliders (10) are respectively provided corresponding to several straight grooves (21). A connecting groove (22) is provided between adjacent straight grooves (21). The connecting groove (22) is connected to the ends of two straight grooves (21) that are far apart from each other. The straight grooves (21) are arranged in an internal spiral structure. The sliders (10) slide with the straight grooves (21) and the connecting grooves (22). The outer wall of the pad (20) is provided with toothed grooves. The bottom surface of the top plate (5) is rotatably connected to a worm (23) through a mounting seat. The worm (23) meshes with the toothed grooves.

6. A roadbed and pavement modal testing instrument according to claim 5, characterized in that: The height measurement module includes a laser rangefinder (24), which is vertically fixed to the bottom surface of the pad (20).

7. A roadbed and pavement modal testing instrument according to claim 2, characterized in that: The monitoring module includes a force sensor, an acceleration sensor, and a velocity sensor, which are respectively installed in the mounting slot.

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