CN-122016633-A - Multidirectional coupling pavement loading test device and method based on dynamic triaxial apparatus

CN122016633ACN 122016633 ACN122016633 ACN 122016633ACN-122016633-A

Abstract

The invention relates to the technical field of road engineering test, in particular to a multidirectional coupling road surface loading test device and method based on a dynamic triaxial apparatus. The sample detection device consists of a computer, a strain gauge, a force sensor and an impact control system, and is used for realizing data acquisition and control, the sample fixing device adopts a double-layer steel table and a sample box body and is used for installing a pavement sample, the hydraulic loading device is used for applying axial creep and lateral dynamic disturbance load through four hydraulic cylinders, namely, an upper hydraulic cylinder, a lower hydraulic cylinder, a left hydraulic cylinder and a right hydraulic cylinder, and the impact loading device is used for realizing controllable high-energy impact loading through combination of an electromagnet and a pendulum bob. The invention can simulate the coupling action of axial, lateral and impact loads on one device at the same time, truly reflects the mechanical response of the pavement in the actual complex stress state, and has the advantages of stable structure, convenient operation, accurate and reliable data and the like.

Inventors

CUI LI
HOU CHAO
DU SHAOHUA
ZHAI SHENGTIAN
REN WENFENG
HAI RAN
Wang Yazuo
NIU XIAOLONG
ZHENG YI
SUN ZHIHAO
MA JIANJUN
WANG CHAOSHENG

Assignees

河南科技大学

Dates

Publication Date: 20260512
Application Date: 20260126

Claims (8)

1. A multidirectional coupling pavement loading test device based on a dynamic triaxial apparatus is characterized by comprising a sample detection device, a sample fixing device, a hydraulic loading device and an impact loading device, wherein the sample detection device comprises a computer (1), a strain gauge (2), a force sensor (3) and an impact control system (4), the strain gauge (2) comprises a strain gauge (5), the computer (1) is connected with the strain gauge (2), the force sensor (3) and the impact control system (4) through data wires, the strain gauge (2) is connected with the strain gauge (5) through signal wires to form a complete data acquisition and control system, the sample fixing device comprises a double-layer steel table (6), a sample box (7) and a surrounding steel plate (8), the double-layer steel table (6) is tightly welded on the ground through foundation bolts, the sample box (7) is fixed on the upper layer of the double-layer steel table (6) through bolts, the front surface, the upper surface, the lower surface, the left surface and the right surface of the computer (1) are all provided with through holes, the rear surface of the computer is kept in a round shape, the rear surface is kept in a whole through signal wires, the whole data acquisition and control system is formed, the sample box (7) is mounted in the pre-buried cylinder (9) through the pre-buried in the sample box (7) and the hydraulic loading device (9) is mounted in the pavement, and the sample box (9) is mounted in the pavement through the sample box (7) through bolts, and the sample box (9) is mounted in the whole pavement, and the pavement is loaded on the pavement, and the pavement is loaded The device comprises a lower hydraulic cylinder (11), a left hydraulic cylinder (12), a right hydraulic cylinder (13) and a hydraulic system (16), wherein the upper hydraulic cylinder (10) and the lower hydraulic cylinder (11) correspond to the upper surface and the lower surface of a sample box body (7) through corresponding through holes on the upper layer and the lower layer of a double-layer steel table (6) and through holes on the upper surface of a triangular steel bracket (19), the left hydraulic cylinder (12) and the right hydraulic cylinder (13) correspond to the left surface and the right surface of the sample box body (7) through the triangular steel bracket (19), the triangular steel bracket (19) is tightly welded and fixed on the ground on two sides of the double-layer steel table (6) through anchor bolts, a trapezoidal steel plate (15) arranged on the left side, the right side and the upper side is provided with holes corresponding to the through holes of the sample box body (7) for bolting the hydraulic cylinders, the hydraulic system (16) is arranged in a space below the double-layer steel table (6) and is connected with oil inlets and outlets (18) of the hydraulic cylinders through high-pressure oil pipes (17), the impact loading device comprises a rectangular steel bracket (14), an electric hammer controller (28), a suspension iron hammer (21) and an electromagnet (22) are tightly welded on the two sides of the double-layer steel table (6) through anchor bolts, the device is characterized in that the device is positioned on the same horizontal plane in front of a sample box body (7), a hanging steel pipe (20) is connected with a rectangular steel bracket (14) through a hinge joint (23), an impact hammer (21) is welded at the tail end of the hanging steel pipe (20), a rubber buffer pad (24) with strong adhesion is arranged at the bottom of the impact hammer, an electromagnet (22) is fixed right above the sample box body (7) through an adjustable supporting steel pipe (25) through a bolt, the adjustable supporting steel pipe (25) is tightly welded on the rectangular steel bracket (14), and an impact control system (4) is welded on the rectangular steel bracket (14) and is connected with the electromagnet (22) through a cable.
2. The multi-directional coupling pavement loading test device based on the dynamic triaxial apparatus according to claim 1, wherein the double-layer steel table (6) is of a channel steel welding frame structure, the upper layer table top is provided with a positioning hole corresponding to the through hole of the sample box body (7), and the lower layer frame is provided with a hydraulic cylinder mounting and fixing hole which is fixed by a bolt.
3. The multi-directional coupling road surface loading test device based on the dynamic triaxial apparatus according to claim 1, wherein the hydraulic system (16) comprises an oil tank (161), a control valve group, an electrohydraulic servo controller (162) and an oil inlet and outlet (163), and the output, loading speed and dwell time of the four hydraulic cylinders can be independently or independently controlled by a computer.
4. The multi-directional coupling road surface loading test device based on the dynamic triaxial apparatus according to claim 1, wherein the triangular steel bracket (19) is welded with a stable structure, a trapezoid steel plate (15) is arranged on the left, right, upper three sides and is provided with a hydraulic cylinder installation fixing hole (27), the trapezoid steel plate is fixed by bolts, and the trapezoid steel plate is welded on the triangular steel bracket (19).
5. The multi-directional coupling road surface loading test device based on the dynamic triaxial apparatus according to claim 1, wherein the impact control system (4) comprises a programmable controller, a high-power direct current power supply and a relay switch, the magnitude of magnetic force is controlled by adjusting exciting current and energizing time of the electromagnet (22), and the impact height is adjusted by controlling the swing angle of the hanging steel pipe (20), so that the accurate control of impact energy is realized.
6. A test method of a multidirectional coupling road surface loading test device based on the dynamic triaxial apparatus according to any one of claims 1 to 5, characterized by comprising the following steps, Firstly, preparing and installing a sample, namely placing a pavement sample (9) pre-embedded with a strain gauge (5) into a sample box body (7), and fixing the sample box body (7) on the upper layer of a double-layer steel table (6) through bolts to ensure that all through holes are aligned; Step two, connecting and debugging the hydraulic system, connecting the hydraulic system (16) with oil ways of all the hydraulic cylinders, controlling the hydraulic system (16) to carry out no-load debugging through a computer (1), and checking whether the hydraulic cylinders act normally or not; Step three, preparing an impact system, namely swinging a suspension steel pipe (20) to a preset angle through an impact control system (4), adjusting the position of an electromagnet (22), and setting impact parameters; step four, calibrating a detection system, namely connecting a computer (1), a strain gauge (2), a force sensor (3) and a strain gauge (5) through wires, and performing sensor zero calibration and signal test; The method comprises the steps of performing a multidirectional coupling loading test, firstly starting a hydraulic system (16), applying axial creep load and lateral disturbance load according to a preset program, then triggering an impact control system (4) at a preset moment, and firstly electrifying an electromagnet (22) to adsorb an impact hammer (21), and completing impact loading at the impact moment in a power-off release mode; step six, data acquisition and analysis, namely acquiring test data in real time through the strain gauge (5) and the force sensor (3), transmitting the test data to the computer (1) for processing, and drawing a load-time curve and a strain-time curve; And step seven, test termination and data processing, stopping loading after a preset test termination condition is reached, finishing test data, and analyzing the mechanical response characteristic of the pavement material under the multidirectional coupling load.
7. The test method of the multidirectional coupling pavement loading test device based on the dynamic triaxial apparatus according to claim 6, wherein the pavement test piece (9) is an asphalt mixture cylinder test piece or a cement concrete cube test piece.
8. The test method of the multidirectional coupling road surface loading test device based on the dynamic triaxial apparatus is characterized in that the strain gauge (2) is a dynamic resistance strain gauge, the sampling frequency is not lower than 1kHz, the force sensor (3) is a spoke type force sensor, and the measuring range is 0-50Kn.

Description

Multidirectional coupling pavement loading test device and method based on dynamic triaxial apparatus Technical Field The invention relates to the technical field of road engineering test, in particular to a multidirectional coupling pavement loading test device and method based on a dynamic triaxial apparatus. Background With the increasing traffic volume and the increasing vehicle axle load, road surfaces are subjected to complex multidirectional coupling load in actual use. The loads mainly comprise axial creep stress generated by long-term running of the vehicle in the road advancing direction, dynamic disturbance stress generated by interaction of adjacent roads or traffic flows on two sides of the road, and instantaneous impact load generated by uneven pavement during running of the vehicle. The traditional pavement material performance testing equipment, such as a dynamic triaxial apparatus, can better simulate axial circulating load and lateral disturbance load, but is difficult to truly reproduce the coupling effect of the multidirectional load, and particularly cannot effectively simulate high-energy instantaneous impact load. In the prior art, partial scholars try to realize multi-directional loading by combining different loading devices, but the problems of complex system, poor coordination among loading systems, high cost and the like exist. Especially in the aspect of impact load simulation, the traditional free falling hammer only depends on gravitational potential energy, the impact force is limited, the impact energy and the time sequence are difficult to accurately control, and the simulation requirement of impact load of a heavy vehicle cannot be met. Therefore, the test device capable of integrating axial creep, lateral disturbance and controllable high-energy impact loading is developed, and has important significance for deeply researching the mechanical response and the damage mechanism of the pavement material in a real and complex stress state. Disclosure of Invention In order to solve the problems of difficult simulation of multidirectional load coupling, insufficient impact energy and uncontrollable in the background technology, the invention provides a multidirectional coupling pavement loading test device and a multidirectional coupling pavement loading test method based on a dynamic triaxial apparatus, and the invention adopts the following technical scheme: A multidirectional coupling road surface loading test device based on a dynamic triaxial apparatus comprises a sample detection device, a sample fixing device, a hydraulic loading device and an impact loading device; the sample detection device comprises a computer, a strain gauge, a force sensor and an impact control system, wherein the strain gauge comprises a strain gauge; the computer is connected with the strain gauge, the force sensor and the impact control system through data wires, and the strain gauge is connected with the strain gauge through signal wires to form a data acquisition and control system; the sample fixing device comprises a double-layer steel table, a sample box body and a surrounding steel plate, wherein the double-layer steel table is tightly welded on the ground through foundation bolts, the sample box body is fixed on the upper layer table surface of the double-layer steel table through bolts, the sample box body is of a five-face tightly welded steel box structure, round through holes are formed in the front face, the upper face, the lower face, the left face and the right face of the sample box body, the rear face is kept complete, the surrounding steel plate is fixed on the rear face of the sample box body through prestressed bolts, a pavement sample is mounted in the sample box body, strain gages are embedded in the pavement sample, the hydraulic loading device comprises an upper hydraulic cylinder, a lower hydraulic cylinder, a left hydraulic cylinder, a right hydraulic cylinder and a hydraulic system, the upper hydraulic cylinder corresponds to the upper face and the lower face of the sample box body through corresponding through holes in the upper layer and the lower layer of the double-layer steel table, the left hydraulic cylinder and the right hydraulic cylinder correspond to the left face and the right face of the sample box body through the triangular steel bracket, the triangular steel bracket is tightly welded on the left face and the right face of the sample box body through the triangular steel bracket, the surrounding steel plate is fixed on the ground on the two sides of the double-layer steel table through the foundation bolts, the pavement sample is mounted in the pavement sample in the sample box body, the pavement sample is embedded in the pavement loading device comprises strain gages, the strain gages are embedded in the hydraulic cylinder and the hydraulic cylinder is arranged in the corresponding to the hydraulic cylinder through the upper through holes and the correspo