Asphalt thickness measuring device for pavement construction

Abstract

The invention belongs to the technical field of asphalt pavement thickness measurement, and particularly relates to a pavement construction asphalt thickness measuring device which comprises a movable base, a top plate and a stand column and further comprises a hydraulic cylinder fixedly arranged at the center of the top plate, a driving shell is fixedly arranged at the movable end of the hydraulic cylinder, and a first motor is fixedly arranged in the driving shell. The hydraulic cylinder can be controlled by the PLC to drive the rotary drum to automatically drill into the asphalt pavement, and the downward moving depth of the rotary drum is accurately controlled by means of electric signal feedback of the depth detection mechanism; after drilling is completed, an asphalt core sample is automatically clamped through an electrified magnetic block and an arc-shaped clamping plate, it is ensured that the core sample cannot be damaged due to too large external force during clamping through a clamping force detection mechanism, and the manual operation intensity is reduced; and finally, an ultrasonic detector is driven by a second motor to automatically measure the thickness of the asphalt core sample, each material layer can be measured based on a pulse reflection method, and the PLC automatically calculates and processes data, so that the measurement efficiency is greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of asphalt pavement thickness measurement, and in particular relates to an asphalt thickness measuring device for pavement construction. Background Art

[0002] In road construction, asphalt pavement is widely used in various highway and urban road projects due to its advantages such as good driving comfort, skid resistance and durability. Among them, the thickness of asphalt pavement is one of the key parameters that determine the bearing capacity and service life of the pavement structure. Accurately measuring the asphalt thickness plays an indispensable role in ensuring the quality of pavement construction.

[0003] At present, when measuring the thickness of asphalt pavement, the core drilling measurement method is the most common operation method, which requires construction personnel to use core drilling equipment to drill asphalt core samples. For example, the announcement: CN118049953B discloses a road construction asphalt pavement thickness measurement component. However, in the actual operation process, it is found that after the construction personnel complete the drilling of the asphalt core sample, the construction personnel need to use a clamp to take the core sample out of the drill hole, and finally use a handheld measuring ruler to measure the thickness of the core sample. However, the manual operation of taking the clamp to take out the core sample and then using the handheld measuring ruler to measure (because the asphalt core sample is usually composed of multiple material layers, the construction personnel also need to measure and record the thickness of each material layer one by one, which takes a lot of time). The construction personnel need to maintain a specific posture for a long time and repeat the operation, which is extremely labor-intensive and reduces work efficiency; moreover, when the clamp is clamping the top position of the asphalt core sample, if the force of the clamping part is too large, the top of the asphalt core sample will be damaged, resulting in the actual size of the asphalt core sample becoming smaller, reducing the accuracy of the thickness measurement.

[0004] Therefore, a device for measuring asphalt thickness in road construction is proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a device for measuring asphalt thickness in road construction in view of the above problems.

[0006] To achieve the above object, the present invention adopts the following technical scheme: a road construction asphalt thickness measuring device, comprising a mobile base, a top plate and a column, wherein the column is arranged between the mobile base and the top plate, and further comprising: A hydraulic cylinder is fixedly arranged at the center of the top plate, and a driving shell is fixedly arranged at the moving end of the hydraulic cylinder, a first motor is fixedly arranged inside the driving shell, and a rotating shaft extending downward is fixedly arranged at the output end of the first motor; A rotating drum is fixedly arranged at the lower end of the rotating shaft, and a moving hole is opened at the top of the moving base corresponding to the position of the rotating drum; A water spray cooling mechanism is arranged on one side of the top of the movable base, and a water outlet of the water spray cooling mechanism extends to one side of the interior of the movable hole; A depth detection mechanism is arranged inside the rotating drum; An asphalt core sample clamping mechanism is arranged at the lower part of the inner wall of the rotating drum; An asphalt core sample clamping force detection mechanism is arranged inside the asphalt core sample clamping mechanism; An asphalt core sample thickness detection mechanism is arranged inside the rotating drum; A Bluetooth wireless communication module is arranged on the inner wall of the rotating drum, and a storage battery is fixedly arranged on the inner wall of the rotating drum; The PLC controller is fixedly mounted on the column, and the hydraulic cylinder, the first motor, the water spray cooling mechanism, the depth detection mechanism, the asphalt core sample clamping mechanism, the asphalt core sample clamping force detection mechanism, and the asphalt core sample thickness detection mechanism are all electrically connected to the PLC controller via the Bluetooth wireless communication module.

[0007] Preferably, the water spray cooling mechanism includes a water tank fixedly arranged on the top of the movable base, a water pump is fixedly arranged inside the water tank, and a water spray pipe extending to the inside of the movable hole is fixedly arranged at the output end of the water pump.

[0008] Preferably, the depth detection mechanism includes an insulating baffle fixedly arranged inside the rotating drum, a top rod is vertically slidably provided in the middle part of the insulating baffle, a top block is rotatably provided at the lower end of the top rod, and the bottom of the top block is flush with the bottom of the rotating drum, an insulating mounting block is fixedly arranged at the upper end of the top rod, a polypropylene sliding sleeve is fixedly arranged on the side wall of the insulating mounting block, an insulating fixing seat is fixedly arranged on the inner side wall of the upper end of the rotating drum, an aluminum sliding rod is fixedly arranged between the insulating baffle and the insulating fixing seat, the polypropylene sliding sleeve is slidably connected to the aluminum sliding rod, a charge collection circuit module is fixedly arranged on the inner side wall of the rotating drum, and the charge collection circuit module and the polypropylene sliding sleeve as well as the charge collection circuit module and the aluminum sliding rod are electrically connected through conductive carbon paste electrodes.

[0009] Preferably, the asphalt core sample clamping mechanism includes two arc-shaped clamping plates symmetrically arranged inside the rotating drum, and placement grooves for placing the arc-shaped clamping plates are provided on both sides of the interior of the rotating drum, a first spring is fixed between the outer wall of the arc-shaped clamping plate and the side wall of the placement groove, a permanent magnet block is fixed on the side wall of the arc-shaped clamping plate, and an electromagnetic block is fixed on the side wall of the placement groove and at a position corresponding to the position of the permanent magnet block.

[0010] Preferably, the asphalt core sample clamping force detection mechanism includes a pressure sensor, wherein an inner side wall of one of the arc-shaped clamping plates is provided with a mounting groove, a mounting plate is provided inside the mounting groove, the pressure sensor is fixed on the side of the mounting plate, and a second spring is fixed between the side of the mounting plate and the side wall of the mounting groove.

[0011] Preferably, the top and bottom of the mounting plate are fixedly provided with limit blocks, and the top and bottom of the mounting groove are provided with limit grooves matched with the limit blocks.

[0012] Preferably, the asphalt core sample thickness detection mechanism includes an ultrasonic detector, a cavity is provided inside one side of the rotating drum, a second motor is fixedly provided on the top of the cavity, a screw rod is fixedly provided on the output end of the second motor, a slider is threadedly provided on the rod wall of the screw rod, a limit rod is fixedly provided on one side of the interior of the cavity, the slider is slidably connected to the limit rod, the ultrasonic detector is fixedly arranged on the side wall of the slider, and a wear-resistant tempered glass window is provided on the inner wall of the rotating drum and at the position of the cavity.

[0013] Preferably, the number of the columns is four, and a side panel for mounting the PLC controller is fixed between two of the columns.

[0014] Compared with the prior art, the present invention has the following beneficial effects: Through the provision of the hydraulic cylinder, the first motor, the rotating drum and the depth detection mechanism, the PLC controller controls the hydraulic cylinder to extend at a uniform speed, so that the rotating drum can automatically drill into the asphalt pavement. At the same time, the depth detection mechanism utilizes the electrical signal feedback generated by the sliding of the polypropylene sliding sleeve on the aluminum sliding rod, so that the PLC controller can accurately grasp the downward movement depth of the rotating drum, thereby avoiding excessive wear of the lower end caused by the rotating drum moving too deep and obtaining excess useless parts outside the asphalt core sample. This not only ensures the automation of drilling, but also can accurately control the depth of the rotating drum entering the asphalt pavement according to actual needs, thereby avoiding drilling too deep or too shallow to affect the core sample acquisition and measurement, thereby improving the accuracy and convenience of operation.

[0015] Through the asphalt core sample clamping mechanism and the asphalt core sample clamping force detection mechanism, after the drilling is completed, the PLC controller controls the electromagnetic block to generate repulsive magnetic force, automatically pushes the arc-shaped clamping plate to clamp the asphalt core sample, and the pressure sensor in the asphalt core sample clamping force detection mechanism monitors the clamping force in real time. When the preset threshold is reached, the PLC controller stops increasing the current of the electromagnetic block through the control circuit to ensure that the clamping force is moderate and avoid extrusion damage to the asphalt core sample. The entire clamping process does not require manual use of pliers, which greatly reduces the operation intensity of construction personnel. At the same time, it ensures the integrity of the asphalt core sample and lays the foundation for the subsequent accurate thickness measurement.

[0016] Through the asphalt core sample thickness detection mechanism, the PLC controller controls the second motor to drive the ultrasonic detector to move, and automatically completes the measurement of the asphalt core sample thickness. The ultrasonic detector is based on the pulse reflection method, and utilizes the characteristic changes of ultrasonic waves when propagating in different material layers. It can measure each material layer of the asphalt core sample. During the measurement process, the PLC controller records the time the ultrasonic detector passes through each material layer and calculates the thickness, and automatically completes data processing without manual measurement and recording, which greatly improves the measurement efficiency and reduces human errors, making the measurement results more accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a stereoscopic diagram of a device for measuring asphalt thickness in road construction provided by the present invention; Figure 2 It is a schematic diagram of the cross-sectional plan structure of a device for measuring asphalt thickness in road construction provided by the present invention; Figure 3 The present invention provides a device for measuring the thickness of asphalt in road construction. Figure 2 The schematic diagram of the structure of the rotating drum; Figure 4 The present invention provides a device for measuring the thickness of asphalt in road construction. Figure 3 A three-dimensional view of the two curved splints; Figure 5 The present invention provides a device for measuring the thickness of asphalt in road construction. Figure 3 Structural schematic diagram of the asphalt core sample clamping force detection mechanism; Figure 6 The present invention provides a device for measuring the thickness of asphalt in road construction. Figure 3 A schematic diagram of the structure of the rotating drum cut from another angle; Figure 7 The present invention provides a device for measuring the thickness of asphalt in road construction. Figure 6 Schematic diagram of the structure of the asphalt core sample thickness detection mechanism.

[0018] In the figure: 1 mobile base, 2 top plate, 3 column, 4 hydraulic cylinder, 5 drive shell, 6 first motor, 7 rotating shaft, 8 rotating drum, 9 moving hole, 10 water spray cooling mechanism, 101 water storage tank, 102 water pump, 103 water spray pipe, 11 depth detection mechanism, 111 insulating baffle, 112 top rod, 113 top block, 114 insulating mounting block, 115 polypropylene sliding sleeve, 116 insulating fixing seat, 117 aluminum sliding rod, 118 charge collection circuit module, 12 asphalt core sample clamping mechanism, 121 arc clamping plate, 122 placement slot, 123 a first spring, 124 a permanent magnet block, 125 an electromagnetic block, 13 an asphalt core sample clamping force detection mechanism, 131 a pressure sensor, 132 a mounting slot, 133 a mounting plate, 134 a second spring, 135 a limit block, 136 a limit slot, 14 an asphalt core sample thickness detection mechanism, 141 an ultrasonic detector, 142 a cavity, 143 a second motor, 144 a lead screw, 145 a slider, 146 a limit rod, 147 a wear-resistant tempered glass window, 15 a Bluetooth wireless communication module, 16 a battery, and 17 a PLC controller. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0020] like Figure 1-Figure 7 As shown, a device for measuring asphalt thickness in road construction includes a mobile base 1, a top plate 2 and a column 3, and also includes: A hydraulic cylinder 4 is fixedly arranged at the center of the top plate 2, and a driving shell 5 is fixedly arranged at the moving end of the hydraulic cylinder 4, a first motor 6 is fixedly arranged inside the driving shell 5, and a rotating shaft 7 extending downward is fixedly arranged at the output end of the first motor 6; The rotating drum 8 is fixedly arranged at the lower end of the rotating shaft 7, and a moving hole 9 is opened at the top of the movable base 1 and at a position corresponding to the position of the rotating drum 8; A water spray cooling mechanism 10 is arranged on one side of the top of the mobile base 1, and the water outlet end of the water spray cooling mechanism 10 extends to one side of the inside of the mobile hole 9. The water spray cooling mechanism 10 includes a water tank 101 fixedly arranged on the top of the mobile base 1, and a water pump 102 is fixedly provided inside the water tank 101. A water spray pipe 103 extending to the inside of the mobile hole 9 is fixedly provided at the output end of the water pump 102. The water pump 102 can pump the cooling water inside the water tank 101 into the water spray pipe 103, and then spray it on the contact position between the wall of the rotating drum 8 and the asphalt pavement through the water spray pipe 103, so that the surface of the rotating drum 8 is cooled to avoid the phenomenon of wear of the rotating drum 8 caused by excessive temperature.

[0021] The depth detection mechanism 11 is arranged inside the rotating drum 8. The depth detection mechanism 11 includes an insulating baffle 111 fixedly arranged inside the rotating drum 8. A top rod 112 is vertically slidably arranged in the middle of the insulating baffle 111. A top block 113 is rotatably arranged at the lower end of the top rod 112, and the bottom of the top block 113 is arranged flush with the bottom of the rotating drum 8. An insulating mounting block 114 is fixedly arranged at the upper end of the top rod 112. A polypropylene sliding sleeve 115 is fixedly arranged on the side wall of the insulating mounting block 114. An insulating fixing seat 116 is fixedly arranged on the inner side wall of the upper end of the rotating drum 8. The insulating mounting block 114 and the insulating fixing seat 116 can play the role of insulation and conductivity. A An aluminum slide bar 117 and a polypropylene sleeve 115 are slidably connected to the aluminum slide bar 117. A charge collection circuit module 118 is fixedly provided on the inner wall of the rotating drum 8. The charge collection circuit module 118 and the polypropylene sleeve 115 as well as the charge collection circuit module 118 and the aluminum slide bar 117 are electrically connected via conductive carbon paste electrodes. When the bottom of the top block 113 contacts the asphalt pavement, the asphalt pavement pushes the top block 113 upward, causing the top block 113 to move upward together with the top rod 112. At the same time, the polypropylene sleeve 115 slides on the aluminum slide bar 117. During the sliding process, electric charges are generated due to frictional electrification, and the generated charges are collected by the charge collection circuit module 118.

[0022] The asphalt core sample clamping mechanism 12 is arranged on the lower position of the inner wall of the rotating drum 8. The asphalt core sample clamping mechanism 12 includes two arc-shaped clamping plates 121 symmetrically arranged inside the rotating drum 8. Both sides of the interior of the rotating drum 8 are provided with placement grooves 122 for placing the arc-shaped clamping plates 121. A first spring 123 is fixedly provided between the outer wall of the arc-shaped clamping plate 121 and the side wall of the placement groove 122. A permanent magnet block 124 is fixedly provided on the side wall of the arc-shaped clamping plate 121. An electromagnetic block 125 is fixedly provided on the side wall of the placement groove 122 and at a position corresponding to the position of the permanent magnet block 124. The power supply of the electromagnetic block 125 is turned on, and the current is continuously increased, so that the electromagnetic block 125 itself will continuously generate a repulsive magnetic force on the permanent magnet block 124, pushing the arc-shaped clamping plate 121 to overcome the elastic force of the first spring 123 and move until the arc-shaped clamping plate 121 contacts and clamps the asphalt core sample.

[0023] The asphalt core sample clamping force detection mechanism 13 is arranged inside the asphalt core sample clamping mechanism 12. The asphalt core sample clamping force detection mechanism 13 includes a pressure sensor 131, wherein the inner wall of one arc-shaped clamping plate 121 is provided with a mounting groove 132, and the interior of the mounting groove 132 is provided with a mounting plate 133. The pressure sensor 131 is fixedly arranged on the side of the mounting plate 133, and a second spring 134 is fixedly arranged between the side of the mounting plate 133 and the side wall of the mounting groove 132. The top and bottom of the mounting plate 133 are fixedly provided with limit blocks 135. The top and bottom of the groove 132 are provided with limit grooves 136 that cooperate with the limit block 135 to prevent the mounting plate 133 from falling off from the inside of the mounting groove 132. The mounting plate 133 can slide inside the mounting groove 132 and compress the second spring 134, so that the pressure sensor 131 has the function of elastic expansion and contraction, thereby preventing the pressure sensor 131 from being damaged by excessive extrusion force. The pressure sensor 131 will also come into contact with the asphalt core sample. As the extrusion pressure between the arc-shaped clamping plate 121 and the asphalt core sample gradually increases, the value of the pressure sensor 131 will become larger.

[0024] The asphalt core sample thickness detection mechanism 14 is arranged inside the rotating drum 8. The asphalt core sample thickness detection mechanism 14 includes an ultrasonic detector 141. A cavity 142 is arranged inside one side of the rotating drum 8. A second motor 143 is fixedly arranged on the top of the cavity 142. A screw rod 144 is fixedly arranged on the output end of the second motor 143. A slider 145 is threaded on the rod wall of the screw rod 144. A limit rod 146 is fixedly arranged on one side of the inner part of the cavity 142. The slider 145 is slidably connected with the limit rod 146. The ultrasonic detector 141 is fixedly arranged on the side wall of the slider 145. A wear-resistant tempered glass window 147 is arranged on the inner side wall of the rotating drum 8 and at the position of the cavity 142. The second motor 143 works at a uniform speed to drive the screw rod 144 to rotate at a uniform speed. The screw rod 144 can drive the slider 145 to move at a uniform speed, so that the ultrasonic detector 141 moves at a uniform speed in the vertical direction and emits high-frequency pulse ultrasonic waves. The ultrasonic waves are projected onto the side wall of the asphalt core sample through the wear-resistant tempered glass window 147.

[0025] The Bluetooth wireless communication module 15 is disposed on the inner wall of the rotating drum 8 , and a storage battery 16 is fixedly disposed on the inner wall of the rotating drum 8 .

[0026] The PLC controller 17 is fixedly set on the column 3. There are four columns 3, and the four columns 3 are set at the four corners between the mobile base 1 and the top plate 2. A side panel for installing the PLC controller 17 is fixed between two of the columns 3. The hydraulic cylinder 4, the first motor 6, the water spray cooling mechanism 10, the depth detection mechanism 11, the asphalt core sample clamping mechanism 12, the asphalt core sample clamping force detection mechanism 13, and the asphalt core sample thickness detection mechanism 14 are all connected to the PLC controller 17 through the Bluetooth wireless communication module 15 via electrical signals.

[0027] The operating principle of the present invention is described as follows: the construction personnel first clean up the dust, soil, leaves, stones and other debris on the asphalt road surface, and then use measuring tools such as steel rulers, distance meters, etc. to accurately determine the position of the core measurement on the asphalt road surface according to the detection purpose and relevant standards and specifications. Generally, measurement points are selected at a certain interval and number in different areas and lanes of the road surface, and then use color spray paint, chalk or other marking tools to make clear and obvious marks around the selected measurement points. After that, the construction personnel push the mobile base 1 to move the measuring device to the marked position so that the lower end of the rotating drum 8 is aligned with the marked measurement point position; After the above-mentioned operation preparation is completed, the construction personnel manually operate the PLC controller 17 to start the hydraulic cylinder 4 to extend at a uniform speed through the PLC controller 17. The hydraulic cylinder 4 drives the drive shell 5 and the rotating drum 8 to move downward at a uniform speed, so that the lower end of the rotating drum 8 passes through the moving hole 9 and contacts the asphalt pavement. When the bottom of the top block 113 contacts the asphalt pavement, the asphalt pavement will push the top block 113 upward, so that the top block 113 and the top rod 112 move upward. At the same time, the polypropylene sliding sleeve 115 slides on the aluminum sliding rod 117. During the sliding process, electric charges are generated due to friction electrification. The generated charges are collected by the charge collection circuit module 118. The charge collection circuit module 118 is composed of a rectifier circuit and an energy storage capacitor. The rectifier circuit can The alternating positive and negative charges generated by friction are converted into unidirectional charges, which are then stored in the energy storage capacitor to achieve charge accumulation and stable output of electrical signals. The output electrical signals are filtered and amplified, and then fed back to the PLC controller 17 through the Bluetooth wireless communication module 15. As the polypropylene sleeve 115 continues to slide on the aluminum slide bar 117, the PLC controller 17 can obtain continuous feedback of the electrical signals. Due to the different electron affinities between the polypropylene material and the aluminum material, when the polypropylene sleeve 115 slides on the aluminum slide bar 117, electrons are transferred at the contact point, and sliding intensifies charge separation, accumulating to form friction potential and surrounding electrostatic fields. The nearby electrodes are induced to generate charges by the electric field, which are rectified into unidirectional flows by the rectification circuit to charge the energy storage capacitor. After the collection is completed, the electrical signal conditioning circuit first amplifies the voltage signal of the energy storage capacitor, and then filters and reduces the noise before feeding it back to the PLC controller 17 through the Bluetooth wireless communication module 15. The PLC controller 17 is internally configured with a Bluetooth receiving device, which can receive the Bluetooth signal and decode it to restore it to the original electrical signal information, thereby realizing data feedback. When the polypropylene sleeve 115 does not move, there is no friction or relative motion, and no friction potential will be generated, so there will be no corresponding charge generation and electrical signal feedback to the PLC controller 17. After receiving the electrical signal, the PLC controller 17 immediately starts the first motor 6 and the water pump 102 and starts the built-in timer. The first motor 6 can drive the drum 8 to rotate and cooperate with the hydraulic cylinder 4 moves downward to drill holes in the asphalt pavement. The pump 102 can pump the cooling water in the water tank 101 into the water spray pipe 103, and then spray the cooling water on the contact position between the drum wall of the drum 8 and the asphalt pavement through the water spray pipe 103, so that the surface of the drum 8 is cooled to avoid the phenomenon of excessive temperature causing wear of the drum 8. The PLC controller 17 can calculate the depth of the drum 8 inserted into the asphalt pavement through the built-in program (assuming that the extension speed of the hydraulic cylinder 4 pushing the drum 8 is 0.03 m / s, and the downward movement time is 10 seconds. According to the relationship between speed, time and displacement, the formula s1=v1t1, where s1 is the displacement, that is, the downward movement depth of the drum 8 in this case; v1 is the speed; t1 is the time, the downward movement depth of the drum 8 can be calculated as: 0.3 meters), the downward movement depth of the drum 8 will be displayed on the display of the PLC controller 17 for the construction personnel to observe. The construction personnel control the downward movement depth of the drum 8 by observing the depth value on the display. When the downward movement depth exceeds the asphalt pavement (for example, if the thickness of the asphalt pavement is 0.5 meters, the drum 8 can be stopped when the downward movement depth exceeds 0.52 meters), the PLC controller 17 is operated to immediately stop the operation of the hydraulic cylinder 4 and the first motor 6. When the drum 8 stops moving downward, it is prevented from excessive wear of the lower end caused by excessive downward movement of the drum 8 and obtaining unnecessary parts outside the asphalt core sample. At the same time, the polypropylene sliding sleeve 115 stops sliding on the aluminum sliding rod 117. At this time, the PLC controller 17 will not receive the feedback of the electrical signal, indicating that the drilling of the asphalt core sample is completed, and the built-in timer of the PLC controller 17 will no longer count the downward movement position of the drum 8;. When the built-in timer of the PLC controller 17 stops counting, it will immediately control the power circuit of the electromagnetic block 125, so that the power of the electromagnetic block 125 is turned on, and the current of the electromagnetic block 125 continues to increase (the PLC controller 17 can control the electromagnetic block 125 to be continuously energized by the digital output control relay), so that the electromagnetic block 125 itself will generate a repulsive magnetic force on the permanent magnet block 124, and push the arc clamping plate 121 to overcome the elastic force of the first spring 123 and move until the arc clamping plate 121 contacts and clamps the asphalt core sample (because there are two arc clamping plates 121, the asphalt core sample can be wrapped and clamped). When the arc clamping plate 121 contacts the asphalt core sample, the pressure sensor 131 also contacts the asphalt core sample. As the extrusion pressure between the arc clamping plate 121 and the asphalt core sample gradually increases, the pressure sensor 1 When the value of 31 increases (because the pressure sensor 131 is arranged on the mounting plate 133, and the mounting plate 133 is slidable and connected to the second spring 134, the pressure sensor 131 has the function of elastic expansion and contraction, so as to avoid damage to the pressure sensor 131 caused by excessive extrusion force), the pressure sensor 131 will feed back an electrical signal to the PLC controller 17 through the Bluetooth wireless communication module 15. When the pressure value detected by the pressure sensor 131 reaches the threshold value preset in the PLC controller 17, the PLC controller 17 immediately stops increasing the current to the electromagnetic block 125 by controlling the power supply circuit, and makes the power supply circuit pass the electromagnetic block 125 with a stable current, so that the arc clamping plate 121 maintains a stable and continuous clamping force on the asphalt core sample, so as to avoid the phenomenon of extrusion damage to the asphalt core sample. At this time, the clamping action of the asphalt core sample is completed; When the asphalt core sample is clamped, the asphalt core sample is connected to the rotating drum 8, and the PLC controller 17 controls the hydraulic cylinder 4 to retract and start the second motor 143 to work at a uniform speed. The hydraulic cylinder 4 retracts to take the rotating drum 8 out from the inside of the asphalt pavement, so that the asphalt core sample is taken out together, and there is no need for construction personnel to take out the clamps, which reduces the operation intensity of construction personnel. At the same time, the asphalt core sample clamped in the rotating drum 8 is taken out, and the second motor 143 can drive the screw rod 144 to rotate at a uniform speed when working, and the screw rod 144 can drive the slider 145 to move at a uniform speed, so that the ultrasonic detector 141 moves at a uniform speed in the vertical direction and emits high-frequency pulse ultrasonic waves. The ultrasonic waves are projected onto the side wall of the asphalt core sample through the wear-resistant tempered glass window 147, and the ultrasonic detector The ultrasonic detector 141 detects the material layers of the asphalt core sample based on the pulse reflection method, and uses the difference in acoustic impedance of different material layers to cause the ultrasonic wave to produce characteristic changes. The transmitting circuit of the ultrasonic detector 141 drives the piezoelectric crystal of the probe to vibrate, and emits ultrasonic waves to enter the asphalt core sample. When the ultrasonic wave is inside each material layer, the ultrasonic wave propagates relatively stably. When the ultrasonic wave reaches the critical point of each material layer, due to the different acoustic impedances of adjacent material layers, part of the ultrasonic wave is reflected at the interface according to the reflection law, and part is refracted into the next layer according to Snell's law. In the process of propagation, multiple reflections and scattering may occur due to the interface or inhomogeneous bodies in the material, and the energy gradually decays. The reflected wave returns to the probe, and the piezoelectric crystal converts its vibration into a weak electrical signal through the inverse piezoelectric effect, which is amplified and filtered by the receiving circuit of the detector. The processed electrical signal is fed back to the PLC controller 17. When the ultrasonic wave emitted by the ultrasonic detector 141 passes through each material layer of the asphalt core sample, the ultrasonic wave propagates relatively stably, and at this time, the built-in timer of the PLC controller 17 will record the time when the ultrasonic detector 141 passes through each material layer, and then the length of each material layer of the asphalt core sample passed by the ultrasonic detector 141 is calculated through the built-in program of the PLC controller 17. This length is the thickness of each material layer. The built-in program of the PLC controller 17 sums the thickness of multiple material layers to obtain the thickness of the asphalt core sample (assuming that the speed of the ultrasonic detector 141 driven by the second motor 143 is 0.02 m / s, and the downward movement time is 10 seconds. According to the speed, time and The relationship formula of displacement is s2=v2t2, where s2 is displacement, which is the thickness of the asphalt core sample here; v2 is speed; t2 is time, and the thickness of each material layer of the asphalt core sample can be calculated as: 0.2 meters, and then the thickness of multiple material layers is added together to get the thickness of the asphalt core sample). This process can automatically complete the removal of the rotating drum 8 and the asphalt core sample and the measurement of the thickness of the asphalt core sample, without manual operation, reducing the intensity of manual operation and improving the efficiency of measurement. During the measurement process, the bottom of the asphalt core sample may have a small amount of excess base or other structural layer materials. When the ultrasonic detector 141 moves to the bottom position, it will measure the thickness of the excess material, and the built-in system program of the PLC controller 17 will automatically subtract it; After the measurement is completed, the construction personnel operate the PLC controller 17 to disconnect the power supply of the electromagnetic block 125, so that the repulsive magnetic force of the electromagnetic block 125 on the permanent magnet block 124 disappears, and the arc clamping plate 121 retracts into the placement groove 122 under the elastic force of the first spring 123 and separates from the asphalt core sample. At this time, the asphalt core sample can automatically fall from the inside of the rotating drum 8, and the construction personnel can then recover the asphalt core sample.

[0028] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A road construction asphalt thickness measuring device, comprising a mobile base (1), a top plate (2) and a column (3), wherein the column (3) is arranged between the mobile base (1) and the top plate (2), and characterized in that: Also includes: A hydraulic cylinder (4) is fixedly arranged at the center of the top plate (2), and a driving shell (5) is fixedly arranged at the movable end of the hydraulic cylinder (4), a first motor (6) is fixedly arranged inside the driving shell (5), and a rotating shaft (7) extending downward is fixedly arranged at the output end of the first motor (6); A rotating drum (8) is fixedly arranged at the lower end of the rotating shaft (7), and a moving hole (9) is provided at the top of the moving base (1) at a position corresponding to the position of the rotating drum (8); A water spray cooling mechanism (10) is arranged on one side of the top of the movable base (1), and a water outlet end of the water spray cooling mechanism (10) extends to one side of the interior of the movable hole (9); A depth detection mechanism (11) is arranged inside the rotating drum (8); An asphalt core sample clamping mechanism (12) is arranged at a lower position of the inner wall of the rotating drum (8); An asphalt core sample clamping force detection mechanism (13) is arranged inside the asphalt core sample clamping mechanism (12); An asphalt core sample thickness detection mechanism (14) is arranged inside the rotating drum (8); A Bluetooth wireless communication module (15) is arranged on the inner wall of the rotating drum (8), and a storage battery (16) is fixedly arranged on the inner wall of the rotating drum (8); The PLC controller (17) is fixedly mounted on the column (3); the hydraulic cylinder (4), the first motor (6), the water spray cooling mechanism (10), the depth detection mechanism (11), the asphalt core sample clamping mechanism (12), the asphalt core sample clamping force detection mechanism (13), and the asphalt core sample thickness detection mechanism (14) are all connected to the PLC controller (17) via electrical signals via the Bluetooth wireless communication module (15).

2. A road construction asphalt thickness measuring device according to claim 1, characterized in that: The water spray cooling mechanism (10) comprises a water storage tank (101) fixedly arranged on the top of the movable base (1), a water pump (102) fixedly arranged inside the water storage tank (101), and a water spray pipe (103) extending into the interior of the movable hole (9) fixedly arranged at the output end of the water pump (102).

3. The asphalt thickness measuring device for road construction according to claim 1, characterized in that: The depth detection mechanism (11) comprises an insulating baffle (111) fixedly arranged inside the rotating drum (8); a push rod (112) is vertically slidably arranged in the middle of the insulating baffle (111); a push block (113) is rotatably arranged at the lower end of the push rod (112); and the bottom of the push block (113) is flush with the bottom of the rotating drum (8); an insulating mounting block (114) is fixedly arranged at the upper end of the push rod (112); a polypropylene sliding sleeve (115) is fixedly arranged on the side wall of the insulating mounting block (114); and the upper end of the rotating drum (8) is provided with a push rod (112) and a push rod (113) is provided with a push rod (113). An insulating fixing seat (116) is fixedly provided on the inner side wall of the end, an aluminum slide bar (117) is fixedly provided between the insulating baffle (111) and the insulating fixing seat (116), the polypropylene sliding sleeve (115) is slidably connected to the aluminum slide bar (117), and a charge collection circuit module (118) is fixedly provided on the inner side wall of the rotating drum (8), and the charge collection circuit module (118) and the polypropylene sliding sleeve (115) as well as the charge collection circuit module (118) and the aluminum slide bar (117) are electrically connected via conductive carbon paste electrodes.

4. A road construction asphalt thickness measuring device according to claim 1, characterized in that: The asphalt core sample clamping mechanism (12) comprises two arc-shaped clamping plates (121) symmetrically arranged inside the rotating drum (8), and placement grooves (122) for placing the arc-shaped clamping plates (121) are provided on both sides of the inside of the rotating drum (8), and a first spring (123) is fixedly provided between the outer wall of the arc-shaped clamping plate (121) and the side wall of the placement groove (122), and a permanent magnet block (124) is fixedly provided on the side wall of the arc-shaped clamping plate (121), and an electromagnetic block (125) is fixedly provided on the side wall of the placement groove (122) and at a position corresponding to the position of the permanent magnet block (124).

5. A road construction asphalt thickness measuring device according to claim 4, characterized in that: The asphalt core sample clamping force detection mechanism (13) comprises a pressure sensor (131), wherein an inner side wall of one of the arc-shaped clamping plates (121) is provided with a mounting groove (132), a mounting plate (133) is provided inside the mounting groove (132), the pressure sensor (131) is fixedly arranged on a side surface of the mounting plate (133), and a second spring (134) is fixedly arranged between the side surface of the mounting plate (133) and the side wall of the mounting groove (132).

6. A road construction asphalt thickness measuring device according to claim 5, characterized in that: Limit blocks (135) are fixedly provided at the top and bottom of the installation plate (133), and limit grooves (136) matching with the limit blocks (135) are provided at the top and bottom of the installation groove (132).

7. The asphalt thickness measuring device for road construction according to claim 1, characterized in that: The asphalt core sample thickness detection mechanism (14) comprises an ultrasonic detector (141); a cavity (142) is provided inside one side of the rotating drum (8); a second motor (143) is fixedly provided on the top of the cavity (142); a screw rod (144) is fixedly provided on the output end of the second motor (143); a slider (145) is threadedly provided on the rod wall of the screw rod (144); a limit rod (146) is fixedly provided on one side of the interior of the cavity (142); the slider (145) is slidably connected to the limit rod (146); the ultrasonic detector (141) is fixedly provided on the side wall of the slider (145); and a wear-resistant tempered glass window (147) is provided on the inner side wall of the rotating drum (8) and at the position of the cavity (142).

8. The asphalt thickness measuring device for road construction according to claim 1, characterized in that: The number of the columns (3) is four, wherein a side plate for mounting the PLC controller (17) is fixed between two of the columns (3).

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