CN112858047B - Drop hammer type deflection measuring device - Google Patents
Drop hammer type deflection measuring device Download PDFInfo
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- CN112858047B CN112858047B CN202110182490.1A CN202110182490A CN112858047B CN 112858047 B CN112858047 B CN 112858047B CN 202110182490 A CN202110182490 A CN 202110182490A CN 112858047 B CN112858047 B CN 112858047B
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- drop hammer
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- travelling belt
- frame
- belt
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/30—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight
- G01N3/303—Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight generated only by free-falling weight
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
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- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention relates to a drop hammer deflection measuring device, which comprises a chassis, wherein a travelling mechanism and a drop hammer mechanism are arranged on the chassis, the drop hammer mechanism comprises a machine frame, a drop hammer and a drop hammer driving mechanism for driving the drop hammer to move upwards, the travelling mechanism comprises a left travelling belt and a right travelling belt which are arranged at intervals left and right, each of the left travelling belt and the right travelling belt comprises an upper travelling belt part and a lower travelling belt part, a force transmission end is arranged on the upper side of the lower travelling belt part of the left travelling belt and/or the right travelling belt and used for rolling contact fit or sliding contact fit with the upper end of the lower travelling belt part of the left travelling belt and/or the right travelling belt, and the lower end of the machine frame passes through a gap between the left travelling belt and the right travelling belt and is in transmission connection with the force transmission end.
Description
Technical Field
The invention relates to a drop hammer type deflection measuring device in the deflection measuring field.
Background
The drop hammer type deflection meter (FWD for short) is generated in the beginning of the 70 th century and simulates the instantaneous impact action of automobile load on the road surface to obtain the instantaneous deformation condition of the road surface, and the measurement result is relatively accurate and has large information quantity. Compared with the traditional Beckman beam force measurement deflection, the dynamic load measuring device has the characteristics of convenience in use, rapidness, safety, labor saving, simulation of actual conditions to apply dynamic load, and suitability for long-distance and continuous measurement.
The existing drop hammer type deflection instrument comprises a chassis, a traveling mechanism, a drop hammer mechanism and a microcomputer control system, wherein the traveling mechanism comprises four traveling wheels rotatably assembled on the chassis, the drop hammer mechanism comprises a loading system and a displacement sensor, and the microcomputer control system comprises a control and data acquisition processing part. The working principle of the device is that a drop hammer with certain mass is lifted to a certain height, when a travelling mechanism runs to a designated position, a bearing plate is lowered, the bearing plate is contacted with the ground, the drop hammer falls freely, the force of the drop hammer is transmitted to the road surface through the bearing plate, so that a pulse load is applied to the road surface, the surface of the road surface is caused to generate instant deformation, deformation of the road surface is detected by displacement sensors distributed at different distances from a measuring point, and dynamic deflection and a curved basin generated under the action of dynamic load are obtained through calculation.
The existing drop hammer deflection measuring device has the following problems: when measuring deflection of a road section, a plurality of measuring points need to be selected, namely, after the drop hammer type deflection meter moves a distance, the bearing plate needs to be lowered, and drop hammers fall down to impact, so that the measuring efficiency of each measuring point is related to the measuring efficiency of the whole road section.
Disclosure of Invention
The invention aims to provide a drop hammer type deflection measuring device, which aims to solve the technical problem that deflection detection efficiency is affected due to the fact that a bearing plate needs to be lowered in the prior art.
In order to solve the technical problems, the technical scheme of the invention is as follows:
the drop hammer deflection measuring device comprises a chassis, wherein a travelling mechanism and a drop hammer mechanism are arranged on the chassis, the drop hammer mechanism comprises a machine frame, a drop hammer and a drop hammer driving mechanism for driving the drop hammer to move upwards, the travelling mechanism comprises left travelling belts and right travelling belts which are arranged at intervals left and right, each of the left travelling belts and the right travelling belts comprises an upper travelling belt part and a lower travelling belt part, a force transmission end is arranged on the upper side of the lower travelling belt part of the left travelling belt and/or the right travelling belt and used for rolling contact fit or sliding contact fit with the upper end of the lower travelling belt part of the left travelling belt and/or the right travelling belt, and the lower end of the machine frame passes through a gap between the left travelling belt and the right travelling belt and is in transmission connection with the force transmission end.
The force transmission end is connected with the mechanism frame in a transmission way by being fixed at the bottom of the mechanism frame, a mechanism frame driving mechanism for driving the mechanism frame to move up and down is arranged on the chassis, and the mechanism frame is assembled on the chassis in a guiding way along the up-down direction.
The mechanism frame driving mechanism is a cam driving mechanism arranged between the chassis and the mechanism frame.
The left side walking belt and the right side walking belt are crawler belts or toothed belts.
The travelling mechanism further comprises a front travelling wheel and a rear travelling wheel which are respectively connected with the left travelling belt and the right travelling belt, the drop hammer deflection measuring device further comprises a cross beam, the length of the cross beam extends along the left-right direction, the cross beam is positioned between the front travelling wheel and the rear travelling wheel, a cross beam driving mechanism for driving the cross beam to move up and down is arranged on the chassis, and a plurality of displacement sensors are arranged on the cross beam at intervals along the length direction of the cross beam.
The bottom of the machine frame comprises front vertical beams and rear vertical beams which are arranged front and back, the upper ends of the front vertical beams and the rear vertical beams are connected through connecting longitudinal beams, the front vertical beams, the rear vertical beams and the connecting longitudinal beams form a door-shaped frame, the cross beams penetrate through the door-shaped frame, the center of the force transmission end is provided with a displacement sensor perforation, and one of the displacement sensors penetrates through the displacement sensor perforation.
The beneficial effects of the invention are as follows: compared with the prior art, the invention has the main improvement that the travelling mechanism adopts the left travelling belt and the right travelling belt which are arranged at intervals left and right, so that when deflection values are detected on corresponding road sections, the force transmission end head can always keep contact rolling fit or contact sliding fit with the upper end of the lower travelling belt part of the left travelling belt and/or the right travelling belt, after the drop weight is lifted, the drop weight falls down, the acting force is directly transmitted to the road surface through the machine framework, the force transmission end head and the corresponding travelling belt, the impulse impact on the road surface is realized, the force transmission end head in contact rolling fit or contact sliding fit with the corresponding force transmission belt does not influence the travelling of the corresponding travelling belt, and compared with the prior art, the invention does not need to drop the bearing plate each time, and therefore the technical problem that deflection detection efficiency is influenced by dropping the bearing plate in the prior art is solved.
Drawings
FIG. 1 is a schematic view showing the structure of an embodiment 1 of a falling weight deflection measuring device in the present invention;
FIG. 2 is a schematic illustration of the engagement of the left running belt with the front and rear running wheels of FIG. 1;
FIG. 3 is a schematic illustration of the engagement of the frame and drive head of FIG. 1;
fig. 4 is a schematic structural view of example 2 of the falling weight deflection measuring device in the present invention.
Detailed Description
Example 1 of the drop hammer deflection measuring device of the present invention is shown in fig. 1 to 3: the novel walking belt comprises a chassis 23, wherein the chassis 23 is provided with a walking mechanism and a drop hammer mechanism, the chassis is made of metal, the walking mechanism comprises a left walking belt 18 and a right walking belt 19 which are arranged at intervals left and right, the left walking belt 18 and the right walking belt 19 are composite toothed belts, the walking belt comprises an upper walking belt part 17 and a lower walking belt part 14, the walking mechanism also comprises a front walking wheel 20 and a rear walking wheel 21 which are respectively connected with the left walking belt and the right walking belt, the front walking wheel 20 and the rear walking wheel 21 are in meshed transmission with the corresponding walking belts, and the front walking wheel is a driving wheel driven by a power mechanism.
The drop hammer mechanism comprises a mechanism frame assembled on a chassis along the guiding movement of the vertical direction, the mechanism frame comprises a vertical guide rod 3, a bearing tray 6 is fixed on the vertical guide rod, a driving tray 2 is fixed on the top of the vertical guide rod, a drop hammer 5 is assembled on the vertical guide rod between the bearing tray and the driving tray in a guiding movement manner, a drop hammer driving mechanism connected with the drop hammer in a driving manner is arranged on the driving tray, and the drop hammer driving mechanism comprises a winding drum 1, and a lifting rope 4 connected with the drop hammer is wound on the winding drum.
The chassis is provided with a mechanism frame driving mechanism for driving the mechanism frame to move up and down, the chassis is provided with a supporting tray 8 positioned at the lower side of the bearing tray, the mechanism frame driving mechanism is a cam driving mechanism, the cam driving mechanism comprises a driving cam 7 rotationally assembled on the supporting tray, the driving cam is driven by a corresponding motor, the mechanism frame can be lifted and lowered by a small amplitude through the rotation of the driving cam, the driving cam 7 is rotated, the bearing tray and the mechanism frame can be lifted to a high position by the driving cam, the driving cam is turned over, and the mechanism frame falls to a low position.
The machine frame further comprises a portal frame 9 positioned at the bottom of the vertical guide rod, wherein the portal frame 9 comprises a front vertical beam 30, a rear vertical beam 31 and a connecting longitudinal beam 32 connected to the tops of the front vertical beam and the rear vertical beam, and the connecting longitudinal beam 32 is fixed at the bottom of the vertical guide rod 3. The bottom of the door-shaped frame is fixed with a force transmission end 13, namely the force transmission end is fixed at the bottoms of the front vertical beam and the rear vertical beam, the force transmission end is of a plate-shaped structure, and the bottom of the force transmission end 13 is in contact sliding fit with the upper ends of the lower side running belt parts 14 of the left side running belt and the right side running belt. When the drop hammer freely falls down to impact the bearing tray, the impact force received by the bearing tray is transmitted to the force transmission end through the vertical guide rod and the portal frame, and then transmitted to the road surface through the lower side travelling belt part, so that the impact on the road surface is realized, and the road surface is deformed.
The drop hammer deflection measuring device further comprises a beam 11, the length of which extends along the left-right direction, the beam is positioned between the front traveling wheel and the rear traveling wheel, a beam driving mechanism for driving the beam to move up and down is arranged on the chassis, the beam driving mechanism comprises a beam driving motor and a screw nut mechanism, the beam driving motor is in transmission connection with a nut 15 in the screw nut mechanism, the bottom of a screw 16 in the screw nut mechanism is fixedly connected with the beam 11, and thus, when the nut rotates, the screw can move up and down, and the beam is driven to move up and down. A plurality of displacement sensors 10 are arranged on the cross beam along the length direction at intervals, one of the displacement sensors is a central displacement sensor 12, the central displacement sensor is positioned at the central position of the deflection basin, a displacement sensor perforation is arranged at the center of the force transmission end 13, the central displacement sensor is arranged in the displacement sensor perforation in a penetrating way, and the rest of the displacement sensors are symmetrically distributed on the left side and the right side of the cross beam.
When the vehicle does not travel to the road section to be tested, the beam driving mechanism lifts the height of the beam, so that the influence of the displacement sensor on the traveling of the traveling mechanism is avoided; the driving mechanism of the mechanism frame drives the mechanism frame to be in a high position, and at the moment, the force transmission end is not contacted with the upper ends of the lower side running belts of the left side running belt and the right side running belt, so that the force transmission end cannot be worn. When the road surface is driven to a road section to be tested, the drop hammer driving mechanism lifts the drop hammer to a high position, the driving cams of the mechanism frame driving mechanism overturn, the mechanism frame falls to a low position, the force transmission end is contacted with the lower side traveling belt parts of the left side traveling belt and the right side traveling belt and is in sliding fit, the drop hammer falls to the impact mechanism frame, the mechanism frame transmits impact force to the force transmission end, the impact force is transmitted to the road surface through the lower side traveling belt parts of the left side traveling belt and the right side traveling belt, so that the road surface forms a bending basin, the central displacement sensor can measure the bending basin value of the center of the impact position, and the displacement sensors at other positions can detect the subsidence of the road surface at the corresponding positions and judge whether the road surface at the corresponding positions has collapse risk or not. After deflection measurement is finished, the drop hammer is lifted to a high position again, the height of the mechanism frame is not required to be adjusted, the force transmission end is always kept in contact with the lower side running belt parts of the left side running belt and the right side running belt and in sliding fit, when the drop hammer deflection measuring device moves to the next measuring point, the drop hammer can directly fall down to carry out deflection measurement, the force transmission end and the corresponding running belt form a bearing plate in the prior art, the process of lowering the bearing plate is omitted, and the deflection measuring efficiency of a road section is greatly improved.
In other embodiments of the invention, the bottom of the force-transmitting end may also have rolling elements, such as rolling bearings, in which case the force-transmitting end may be in rolling contact engagement with the upper ends of the lower running portions of the left and right running belts; of course, the left side running belt and the right side running belt can also be crawler belts; the travelling mechanism can also be a follow-up travelling mechanism, and the travelling mechanism can move with the drop hammer type deflection measuring device through a trailer when in use; the force transmission end head can be also provided with a hydraulic force transducer.
Embodiment 2 of the drop hammer deflection measuring device, embodiment 2 is different from embodiment 1 in that the drop hammer deflection measuring device can be applied to deflection measurement of underwater, namely, the bottom surface of water, a sealing cover 40 is arranged on a chassis and is covered on the periphery of a drop hammer, the upper end of the sealing cover is connected with a vent pipe 41, and specifically, the bottom of the sealing cover is positioned on the lower side of a supporting tray. When in use, the travelling mechanism runs below the water surface, the sealing cover is communicated with the outside atmosphere through the vent pipe, the working environment of the drop hammer 5 is still an air environment, the drop hammer 5 is free to fall without being influenced by the resistance of water body, the impact force can be transmitted to the water bottom through the mechanical framework, the force transmission end and the corresponding walking belt, so as to measure the deflection of the water bottom. The drop hammer deflection measuring device in the embodiment can be applied to the deflection measurement of the bottom surface of south-to-north water.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims (5)
1. The utility model provides a drop hammer formula deflection measuring device, includes the chassis, is provided with running gear and drop hammer mechanism on the chassis, and drop hammer mechanism includes the mechanism frame, drops the hammer and drives the drop hammer actuating mechanism that drops the hammer and upwards move, its characterized in that: the travelling mechanism comprises left travelling belts and right travelling belts which are arranged at intervals left and right, each of the left travelling belts and the right travelling belts comprises an upper travelling belt part and a lower travelling belt part, a force transmission end is arranged on the upper side of the lower travelling belt part of the left travelling belt and/or the right travelling belt, the force transmission end is used for being in rolling contact fit or sliding contact fit with the upper end of the lower travelling belt part of the left travelling belt and/or the right travelling belt, the lower end of the mechanism frame passes through a gap between the left travelling belt and the right travelling belt and is in transmission connection with the force transmission end, the mechanism frame comprises a vertical guide rod, a force bearing tray is fixed on the vertical guide rod, a drop hammer is assembled between the force bearing tray and the driving tray in a guiding movement manner, a drop hammer driving mechanism which is in transmission connection with the drop hammer is arranged on the driving tray, the force transmission end is in transmission connection with the mechanism frame through being fixed at the bottom of the mechanism frame, and the upper end of the mechanism frame is provided with a mechanism for moving up and down along the driving frame of the chassis.
2. The drop hammer deflection measurement device of claim 1, wherein: the mechanism frame driving mechanism is a cam driving mechanism arranged between the chassis and the mechanism frame.
3. The drop hammer deflection measurement device of claim 1, wherein: the left side walking belt and the right side walking belt are crawler belts or toothed belts.
4. The drop hammer deflection measuring device according to any one of claims 1 to 3, wherein: the travelling mechanism further comprises a front travelling wheel and a rear travelling wheel which are respectively connected with the left travelling belt and the right travelling belt, the drop hammer deflection measuring device further comprises a cross beam, the length of the cross beam extends along the left-right direction, the cross beam is positioned between the front travelling wheel and the rear travelling wheel, a cross beam driving mechanism for driving the cross beam to move up and down is arranged on the chassis, and a plurality of displacement sensors are arranged on the cross beam at intervals along the length direction of the cross beam.
5. The drop hammer deflection measurement device of claim 4, wherein: the bottom of the machine frame comprises front vertical beams and rear vertical beams which are arranged front and back, the upper ends of the front vertical beams and the rear vertical beams are connected through connecting longitudinal beams, the front vertical beams, the rear vertical beams and the connecting longitudinal beams form a door-shaped frame, the cross beams penetrate through the door-shaped frame, the center of the force transmission end is provided with a displacement sensor perforation, and one of the displacement sensors penetrates through the displacement sensor perforation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110182490.1A CN112858047B (en) | 2021-02-10 | 2021-02-10 | Drop hammer type deflection measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110182490.1A CN112858047B (en) | 2021-02-10 | 2021-02-10 | Drop hammer type deflection measuring device |
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| Publication Number | Publication Date |
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| CN112858047A CN112858047A (en) | 2021-05-28 |
| CN112858047B true CN112858047B (en) | 2023-08-25 |
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| CN202110182490.1A Active CN112858047B (en) | 2021-02-10 | 2021-02-10 | Drop hammer type deflection measuring device |
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Citations (4)
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| CN2869109Y (en) * | 2005-12-30 | 2007-02-14 | 北京航天计量测试技术研究所 | Portable drop hammer benkelman beams deflectometer |
| CN201152841Y (en) * | 2007-12-27 | 2008-11-19 | 北京航天计量测试技术研究所 | Full-automatic monkey hammer type benkelman beams deflectometer |
| CN102466598A (en) * | 2010-11-15 | 2012-05-23 | 北京航天计量测试技术研究所 | Multipoint sensor FWD (Falling Weight Deflectometer) |
| CN111829901A (en) * | 2020-06-30 | 2020-10-27 | 河南牛帕力学工程研究院 | Drop hammer type deflection detection device |
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| JPH06185971A (en) * | 1992-12-16 | 1994-07-08 | Komatsu Shisutetsukusu Kk | Measuring machine for deflection amount of pavement surface |
| CN101250848A (en) * | 2008-03-24 | 2008-08-27 | 山东省交通科学研究所 | Agitation type pavement deflection tester |
| CN205839559U (en) * | 2016-07-27 | 2016-12-28 | 北京中天恒宇科技有限公司 | A kind of drop hammer type deflection testing system |
| CN209854517U (en) * | 2019-04-29 | 2019-12-27 | 北京市路兴公路新技术有限公司 | Quick drop hammer type deflectometer |
| CN110644336B (en) * | 2019-10-26 | 2024-06-07 | 浙江土工仪器制造有限公司 | Multifunctional detection vehicle |
| CN211848794U (en) * | 2020-02-17 | 2020-11-03 | 河北恒奥工程项目管理有限公司 | Convenient road benkelman beams deflectometer detection device |
| CN212459238U (en) * | 2020-05-08 | 2021-02-02 | 郑州维霖工程科技有限公司 | Built-in hydraulic road surface strength detection vehicle |
| CN212505757U (en) * | 2020-06-19 | 2021-02-09 | 浙商检测集团有限公司 | Full-automatic drop hammer type deflection detection device |
| CN215374908U (en) * | 2021-02-10 | 2021-12-31 | 郑州东辰科技有限公司 | Drop hammer type deflection measuring device |
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2021
- 2021-02-10 CN CN202110182490.1A patent/CN112858047B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2869109Y (en) * | 2005-12-30 | 2007-02-14 | 北京航天计量测试技术研究所 | Portable drop hammer benkelman beams deflectometer |
| CN201152841Y (en) * | 2007-12-27 | 2008-11-19 | 北京航天计量测试技术研究所 | Full-automatic monkey hammer type benkelman beams deflectometer |
| CN102466598A (en) * | 2010-11-15 | 2012-05-23 | 北京航天计量测试技术研究所 | Multipoint sensor FWD (Falling Weight Deflectometer) |
| CN111829901A (en) * | 2020-06-30 | 2020-10-27 | 河南牛帕力学工程研究院 | Drop hammer type deflection detection device |
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| CN112858047A (en) | 2021-05-28 |
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