Linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device and method

Abstract

The invention discloses a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device and method, and the device comprises at least two vertical reaction frames, each vertical reaction frame comprises a pair of stand columns and a cross beam, and the cross beam is erected on the opposite sides of the top ends of the stand columns and is fixedly connected with the two stand columns; the loading unit is arranged on the vertical counter-force frame and comprises an actuator, a loading cross beam arranged at the output end of the actuator, a loading vertical beam arranged below the loading cross beam, a guide seat arranged on the side face of the stand column and a simulation vehicle-mounted assembly; the vertical counter-force frame is arranged on the simulation vehicle-mounted assembly, the reciprocating motion unit is arranged on the vertical counter-force frame, the reciprocating motion unit comprises a horizontal counter-force frame, a motor mounting frame arranged on the horizontal counter-force frame and a linear motor arranged on the motor mounting frame, and a vertical load is provided for the simulation vehicle-mounted assembly through the actuator. The reciprocating motion unit provides horizontal force for the simulation vehicle-mounted assembly so as to simulate the dead weight and reciprocating motion of the vehicle.

Description

Technical Field

[0001] The present invention belongs to the technical field of road surface loading test, and more specifically, relates to a linear motor driven reciprocating wheel pressure type road bridge deck fatigue test device and method. Background Art

[0002] The pavement and steel bridge deck components of highways and highway bridges are repeatedly crushed by wheel loads during operation. The damage caused by long-term fatigue loads is the main factor causing damage and failure. The design life of steel structure bridges in my country is generally 100 years, and the design life of pavement is not less than 20 years. However, in actual projects, early damage to pavement or steel bridge decks is common, resulting in additional highway and bridge maintenance costs.

[0003] Highway steel bridge decks are three-dimensional load-bearing components composed of multiple steel plates welded or bolted together. They contain many nodes and complex stress distribution. It is often difficult to obtain accurate fatigue resistance indicators through theoretical calculations. Highway pavement is a stacked system composed of multiple layers, multiple types of stone, cement-based materials, and asphalt-based materials. The performance of different paving schemes varies greatly, and new materials and new processes are constantly being applied. It is also difficult for theoretical calculations to give an effective evaluation of highway pavement layers. Due to the complexity of the performance of highway steel bridge decks and pavement layers, it is common to verify their performance through real-scale reciprocating loading tests for important single projects or large-scale and wide-ranging projects.

[0004] For the full-scale test of highway steel bridge decks, the conventional practice is to use a uniaxial fatigue actuator to perform reciprocating loading under a certain constant amplitude fatigue load on one or more points. Since the loading method is very different from the actual vehicle load, this type of test requires preset key areas of concern for design. For areas outside the key areas of concern, there may be large deviations due to the inconsistency between the boundary conditions and the actual situation. Its accuracy is highly dependent on simulation analysis.

[0005] There are two main types of full-scale tests for pavement: real vehicle tests and simulated vehicle tests. In real vehicle tests, the road surface to be tested is laid on a certain circular track, and a loaded vehicle is used to roll it back and forth. The effective load is proportional to the load of the vehicle, and it can be exactly the same as the actual working conditions. However, the test cost is very high in terms of site, manpower, and time consumption. Simulated vehicle tests can be carried out indoors or outdoors, using some form of wheel loading equipment (simulated vehicle) to simulate the working conditions of wheel reciprocating rolling. The main difficulty lies in how to increase the effective load of the wheel while maintaining a sufficient loading frequency. Summary of the invention

[0006] In view of the above defects or improvement needs of the prior art, the present invention provides a linear motor driven reciprocating wheel pressure type road bridge deck fatigue test device and method, which provides a vertical load for the simulated vehicle-mounted component through an actuator to simulate the vehicle's own weight, and provides a horizontal force for the simulated vehicle-mounted component through a reciprocating motion unit, so that the simulated vehicle moves back and forth on the test piece, thereby realizing an effective loading test on the road surface or bridge deck structure. In addition, during the loading test, no manual participation is required, and the device automatically adjusts the parameters according to the requirements of different environments, thereby increasing the effective loading force on the test piece without increasing the weight of the simulated vehicle, taking into account the requirements of increasing the effective load and maintaining the loading frequency, and realizing an accelerated fatigue damage test of the road pavement or steel bridge deck.

[0007] To achieve the above objectives, according to a first aspect of an embodiment of the present invention, a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device is provided, comprising:

[0008] At least two vertical reaction frames, each vertical reaction frame includes a pair of columns and a crossbeam, the crossbeam is mounted on the opposite sides of the top ends of the columns and is fixedly connected between the two columns;

[0009] A loading unit disposed on the vertical reaction frame, the loading unit comprising an actuator, a loading beam disposed at an output end of the actuator, a loading vertical beam disposed below the loading beam, a guide seat disposed on a side of the column, and a simulated vehicle-mounted component;

[0010] And a reciprocating motion unit arranged on the vertical reaction frame, the reciprocating motion unit includes a horizontal reaction frame, a motor mounting frame arranged on the horizontal reaction frame and a linear motor arranged on the motor mounting frame, the actuator is used to provide a vertical load for the simulated vehicle-mounted component, and the reciprocating motion unit provides a horizontal force for the simulated vehicle-mounted component to simulate the vehicle's own weight and reciprocating movement.

[0011] Furthermore, at least two actuators are provided at the bottom of each beam and are symmetrically installed at both ends of the beam.

[0012] Furthermore, two mounting seats are provided at corresponding positions of the loading crossbeam and the crossbeam;

[0013] A pin is arranged on the mounting seat, the mounting seat on the crossbeam is rotationally connected to the fixed end of the actuator, and the mounting seat on the loading crossbeam is rotationally connected to the actuator.

[0014] Furthermore, the loading vertical beams are used in pairs, parallel and spanning between the multiple loading horizontal beams, and are fixedly connected to the multiple loading horizontal beams;

[0015] A loading track is also provided at the bottom of each loading vertical beam along the length direction. The loading track is a straight track with a protrusion at the bottom.

[0016] Furthermore, the guide seats are provided in a group on each side of the two columns of each vertical reaction frame facing each other, and each group of guide seats includes two limit plates arranged opposite to each other;

[0017] The limit plate is fixed on the column in the vertical direction, and a gap is left between the two limit plates as a guide channel;

[0018] The width of the guide channel is the same as that of the loading beam. Both ends of the loading beam are arranged in the guide channels on the columns on both sides, and the loading beam moves in the guide channel along the vertical direction.

[0019] Furthermore, the simulated vehicle-mounted assembly is arranged at the bottom of the loading vertical beam, including a vehicle body, an axle arranged at the bottom of the vehicle body, a loading wheel arranged on the axle, a guide wheel arranged at the top of the vehicle body, and auxiliary wheels arranged at both sides of the vehicle body;

[0020] The vehicle body is a plate-shaped structure, with a loading wheel mounting seat at the bottom, a guide wheel mounting seat at the top, auxiliary wheel mounting seats at both sides, and wheel axles arranged on the loading wheel mounting seat, the guide wheel mounting seat and the auxiliary wheel mounting seat.

[0021] Furthermore, the loading wheel mounting seat is provided with at least four loading wheels arranged in a square array, the loading wheels are mounted on the loading wheel mounting seat through a wheel axle, and the loading wheels are in contact with the surface of the specimen;

[0022] The guide wheel mounting seat is provided at each of the four corners of the top of the vehicle body, and its width direction position corresponds to the position of the loading track. The guide wheel is installed on the guide wheel mounting seat through the wheel axle, and a groove is provided on its surface along the circumferential direction. The width of the groove is the same as the protrusion of the loading track, and the two form a fit;

[0023] The auxiliary wheel mounting seats are respectively provided with two on both sides of the vehicle body, and the auxiliary wheels are also mounted on the auxiliary wheel mounting seats through wheel axles.

[0024] Furthermore, a bearing platform is provided at the bottom end of the column and on the same side as the guide seat;

[0025] The horizontal reaction frame is arranged on the bearing platform and sandwiched between the columns of each vertical reaction frame;

[0026] Anti-collision blocks are provided on the inner sides of the transverse plates at both ends of the horizontal reaction frame along the width direction, and the anti-collision blocks are made of rubber; guide auxiliary strips are provided on the inner sides of the vertical plates on both sides along the length direction, and the auxiliary wheels on both sides of the vehicle body are in contact with the auxiliary strips on the inner side of the horizontal reaction frame.

[0027] Furthermore, the motor mounting frame spans the horizontal reaction frame along the length direction of the horizontal reaction frame, and both ends are fixed to the horizontal plate of the horizontal reaction frame along the width direction, and the central part of the fixed position is provided with a hollow, and both ends of the hollow position are connected to serve as a mounting position;

[0028] The linear motor is installed in the motor installation position of the motor installation frame, and its output end is connected to the two ends of the vehicle body, and the connection point is also connected by rotation.

[0029] According to another aspect of an embodiment of the present invention, a linear motor driven reciprocating wheel pressure type road bridge deck fatigue test method is provided, comprising:

[0030] S100. Install the test specimens for the simulation test at the experimental site, arrange effective temporary supports, install the experimental device on the temporary supports, and remove the temporary supports after the installation is completed;

[0031] S200. According to the preset fatigue test requirements, the functions of the experimental device are tested separately and linked to ensure the normal use of the device;

[0032] S300, starting the device in the order of increasing the ambient temperature, applying an additional load to the actuator, and driving the simulated vehicle-mounted components, and starting the experiment;

[0033] S400: During the experiment, if a short period of observation is required or the monitoring personnel temporarily leave, all actions of the experimental device shall be suspended;

[0034] S500: After the experiment is completed, the device is stopped in the order of driving the simulated vehicle-mounted components to decelerate and stop, the actuator is unloaded, and the environment is cooled down, and the test is terminated.

[0035] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0036] 1. The linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device of the present invention provides a vertical load to the simulated vehicle-mounted component through an actuator to simulate the dead weight of the vehicle, and provides a horizontal force to the simulated vehicle-mounted component through a reciprocating motion unit, so that the simulated vehicle moves back and forth on the test piece, thereby realizing an effective loading test on the road surface or bridge deck structure. In addition, during the loading test, no manual participation is required, and the device automatically adjusts the parameters according to the requirements of different environments, thereby increasing the effective loading force on the test piece without increasing the dead weight of the simulated vehicle, taking into account the requirements of increasing the effective load and maintaining the loading frequency, and realizing the accelerated fatigue damage test of the road pavement or steel bridge deck.

[0037] 2. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device of the present invention has guide wheels and auxiliary wheels on the simulated vehicle-mounted component, both of which provide guidance for the movement of the simulated vehicle-mounted component to prevent it from swaying during the reciprocating motion, causing the movement of the loading wheel to be out of the predetermined track, affecting the effect of the experiment.

[0038] 3. In the linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device of the present invention, the connection structures at both ends of the actuator and the vehicle body are both rotationally connected, which eliminates the force that produces direction deviation during loading, so that the vertical load and horizontal force of the simulated vehicle-mounted components are not offset, thereby ensuring the effect of the experiment.

[0039] 4. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device of the present invention has a maximum single wheel load of 200kN and an equivalent frequency of 0.13Hz in the steel bridge deck fatigue test, and works 12 hours a day, and can complete 2 million effective loads within 90 days; a single wheel load of 200kN and an equivalent frequency of 0.54Hz in the road pavement accelerated fatigue test, and works 12 hours a day, and can complete 10 million effective loads within 220 days. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic structural diagram of a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to an embodiment of the present invention;

[0041] Figure 2 This is a schematic diagram of the vertical reaction frame structure of a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to an embodiment of the present invention;

[0042] Figure 3 This is a schematic diagram of the structure of a loading unit of a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to an embodiment of the present invention;

[0043] Figure 4 This is a schematic diagram of the actuator connection of a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to an embodiment of the present invention;

[0044] Figure 5 This is a schematic diagram of the structure of a simulated vehicle-mounted component of a linear motor-driven reciprocating wheel-pressure type road and bridge deck fatigue test device according to an embodiment of the present invention;

[0045] Figure 6 This is a schematic diagram of the structure of a reciprocating motion unit of a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to an embodiment of the present invention;

[0046] Figure 7 It is a schematic flow chart of a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test method according to an embodiment of the present invention;

[0047] Figure 8 This is a schematic diagram of a specific flow of step S200 in a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test method according to an embodiment of the present invention;

[0048] Fig. 9 This is a specific flow chart of step S300 in a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test method according to an embodiment of the present invention;

[0049] Fig.10 Schematic diagram of a specific flow of step S500 in a linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test method according to an embodiment of the present invention.

[0050] In all the drawings, the same figure marks represent the same technical features, specifically: 1-vertical reaction frame, 11-column, 12-crossbeam, 2-loading unit, 21-actuator, 22-loading crossbeam, 23-loading vertical beam, 24-guide seat, 25-simulated vehicle-mounted component, 251-vehicle body, 252-axle, 253-loading wheel, 254-guide wheel, 255-auxiliary wheel, 26-loading track, 3-reciprocating motion unit, 31-horizontal reaction frame, 32-motor mounting frame, 33-linear motor. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0052] Example 1

[0053] like Figure 1 As shown, an embodiment of the present invention provides a linear motor driven reciprocating wheel pressure type road bridge deck fatigue test device, comprising: a vertical reaction frame 1, a loading unit 2 arranged between the vertical reaction frames 1, and a reciprocating motion unit 3. The loading unit 2 comprises an actuator 21 and a simulated vehicle-mounted component 25. The actuator 21 provides a vertical load to the simulated vehicle-mounted component 25 to simulate the dead weight of the vehicle. The reciprocating motion unit 3 provides a horizontal force to the simulated vehicle-mounted component 25, so that the simulated vehicle moves back and forth on the specimen, thereby realizing an effective loading test on the road surface or bridge deck structure. In addition, during the loading test, no manual participation is required. The device automatically adjusts the parameters according to the requirements of different environments, thereby increasing the effective loading force on the specimen without increasing the dead weight of the simulated vehicle, taking into account the requirements of increasing the effective load and maintaining the loading frequency, thereby realizing an accelerated fatigue damage test on the road pavement or steel bridge deck.

[0054] like Figure 2 As shown, at least two vertical reaction frames 1 are provided, which are equidistantly arranged on the specimen along the length direction, and each vertical reaction frame 1 includes a pair of columns 11 and a crossbeam 12. The column feet of the columns 11 are connected to the specimen by tensile anchor bolts, and the crossbeam is arranged on the side facing the top of the column 11 and fixedly connected to the two columns 11. The columns 11 and the crossbeam 12 are made of steel not lower than Q345, and their surfaces are coated with anti-corrosion materials.

[0055] Preferably, a fixed reaction floor or equipment pedestal is provided on the specimen, and the column foot of the column 11 is connected to the reaction floor or equipment pedestal through a tensile anchor bolt.

[0056] At least two actuators 21 are provided at the bottom of each cross beam 12 , symmetrically mounted at both ends of the cross beam 12 , and are hydraulic devices or servo motor devices. The maximum load of a single actuator 21 is not less than 500KN.

[0057] like Figure 3 , 4 As shown, the loading unit 2 also includes a loading crossbeam 22 disposed at the output end of the actuator 21, a loading vertical beam 23 disposed below the loading crossbeam 22, and a guide seat 24 disposed on the side of the column 11. Among them, two mounting seats are provided at the corresponding positions of the loading crossbeam 22 and the crossbeam 12, and the mounting seats are provided with pins. The mounting seats on the crossbeam 12 are rotationally connected to the fixed end of the actuator 21, and the mounting seats on the loading crossbeam 22 are rotationally connected to the actuator 21. When non-vertical force appears on the loading crossbeam 22, the mounting seats at both ends of the actuator 21 rotate to eliminate the horizontal force, so that the force output on the loading crossbeam 22 is a stable vertical force. The loading vertical beams 23 are used in pairs, parallel and spanning between multiple loading crossbeams 22, and are fixedly connected to multiple loading crossbeams 22. Each loading vertical beam 23 is provided with a loading track 26 at the bottom along the length direction. The loading track 26 is a straight track with a protrusion at the bottom. It is made of steel material not lower than Q345, and the surface is polished and coated with anti-corrosion paint to prevent it from bending when subjected to force and affecting the experimental effect. The guide seat 24 is provided on each side of the two columns 11 facing each other of each vertical reaction frame 1. Each group of guide seats 24 includes two opposite limit plates, which are fixed on the columns 11 in the vertical direction. A gap is left between the two limit plates as a guide channel. The width of the guide channel is the same as that of the loading crossbeam 22. The two ends of the loading crossbeam 22 are provided in the guide channels on the columns 11 on both sides, and it moves in the vertical direction in the guide channel.

[0058] like Figure 5As shown, the simulated vehicle-mounted component 25 is arranged at the bottom of the loading vertical beam 23, including a vehicle body 251, a wheel axle 252 arranged at the bottom of the vehicle body 251, a loading wheel 253 arranged on the wheel axle 252, a guide wheel 254 arranged at the top of the vehicle body 251, and auxiliary wheels 255 arranged on both sides of the vehicle body 251. The vehicle body 251 is a plate-like structure, with a loading wheel mounting seat at the bottom, a guide wheel mounting seat at the top, and auxiliary wheel mounting seats on both sides. The wheel axle 252 is arranged on the loading wheel mounting seat, the guide wheel mounting seat, and the auxiliary wheel mounting seat. The loading wheel mounting seat is provided with at least four loading wheel mounting seats arranged in a square array, and the loading wheel 253 is mounted on the loading wheel mounting seat through the wheel axle 252, and the loading wheel 253 is in contact with the surface of the specimen, ensuring that the loading wheel 253 is uniformly stressed during vertical loading, and the vertical loading is maintained on the surface of the specimen without generating a deflection angle. The guide wheel mounting seat is provided at each of the four corners of the top of the vehicle body 251, and its width direction position corresponds to the position of the loading track 26. The guide wheel 254 is installed on the guide wheel mounting seat through the wheel axle 252, and its surface is provided with a groove along the circumference. The width of the groove is the same as the protrusion of the loading track 26, and the two form a fit. Two auxiliary wheel mounting seats are provided on each side of the vehicle body 251, and the auxiliary wheel 255 is also installed on the auxiliary wheel mounting seat through the wheel axle 252.

[0059] Preferably, the loading wheel 253 is a pneumatic tire, a solid rubber tire or a steel plate reinforced solid rubber tire, and the pressure between the loading wheel 253 and the sample is maintained between 0.7 MPa and 5 MPa.

[0060] Preferably, the connection positions of the loading wheel 253, the guide wheel 254 and the auxiliary wheel 255 are all provided with bearings to reduce the wear of the wheel shaft 252 or the pin shaft.

[0061] like Figure 6As shown, a bearing platform is also provided at the bottom end of the column 11 and the same side as the guide seat 24, and the reciprocating motion unit 3 includes a horizontal reaction frame 31 provided on the bearing platform, a motor mounting frame 32 provided on the horizontal reaction frame 31, and a linear motor 33 provided on the motor mounting frame 32. The horizontal reaction frame 31 is a rectangular frame, which is fixedly connected to the bearing platform with high-strength bolts, clamped between the columns 11 of each vertical reaction frame 1, and is made of steel material not less than Q345, which is an I-shaped or square cross-section, and the surface is coated with anti-corrosion material. Anti-collision blocks are provided on the inner side of the horizontal plates along the width direction at both ends of the horizontal reaction frame 31, and the anti-collision blocks are made of rubber; guide auxiliary strips are provided on the inner side of the vertical plates along the length direction on both sides, and the guide auxiliary strips are made of smooth rigid materials. The motor mounting frame 32 spans the horizontal reaction frame 31 along the length direction of the horizontal reaction frame 31, and both ends are fixed on the horizontal plate of the horizontal reaction frame 31 along the width direction, and the central part of the fixed position is provided with a hollow, and the two ends of the hollow position are connected to serve as a mounting position. The linear motor 33 is installed in the motor mounting position of the motor mounting frame 32, and its output end is connected to the two ends of the vehicle body 251, and the connection is also connected by rotation. The auxiliary wheels 255 on both sides of the vehicle body 251 are in contact with the auxiliary strips on the inner side of the horizontal reaction frame 31, and when the linear motor 33 drives the simulated vehicle-mounted component 25 to move back and forth, it assists it not to deviate.

[0062] The linear motor 33 further includes a linear magnetic rail and a mover. The linear magnetic rail is fixed on the motor mounting frame 32 , and the mover is rotatably connected to two ends of the vehicle body 251 .

[0063] This experimental device also includes an environmental loading system, which is used to perform environmental loading on the pavement during the accelerated fatigue test, including a frame, enclosure, heating fan, thermal sensor, control system and alarm device. Among them, the frame is made of angle steel or square steel material not lower than Q235, and the exterior is coated with anti-corrosion material, and the frame is also provided with structures of other equipment. The enclosure is a transparent polymer film, which is connected between the frame and the indoor floor, and the connection is a sealed connection to prevent contact with the outside air. The heating fan is arranged on the frame, and its air outlet is aligned with the position of the pavement specimen, and the heating fan is provided with multiple ones to ensure the uniform and stable temperature in the experimental area, and the temperature of the experiment is controlled between 55-65°C. The thermal sensor is a thermocouple sensor, which is arranged in the pavement specimen, and is used to detect the temperature of the pavement during the test, and to adjust the power of the hot fan with feedback information. The warning device is an audible and visual alarm device, which is also connected to a display screen, and its signal input end is also connected to a temperature sensor. The temperature sensor is arranged in an experimental environment surrounded by a frame, and an alarm is sounded when the air and steel structure surface temperature in the experimental environment are higher than 40°C, thereby preventing operators from being scalded during operation.

[0064] Preferably, since the surface of the road pavement or steel bridge deck is inevitably uneven, there is a certain load unevenness when the simulated vehicle-mounted unit walks on the surface of the specimen. A force sensor is also provided at the output end of the actuator 21, and a strain sensor is embedded in the specimen. The load output by the actuator 21 is adjusted by the imbalance information monitored by the force sensor and the strain sensor. At the same time, during the experiment, the load output by the actuator 21 is changed to simulate vehicles with different dead weights.

[0065] Preferably, in the fatigue test of steel bridge deck, the maximum single wheel load is 200kN, the equivalent frequency is 0.13Hz, and the working day is 12 hours, so 2 million effective loadings can be completed within 90 days; in the accelerated fatigue test of pavement, the maximum single wheel load is 200kN, the equivalent frequency is 0.54Hz, and the working day is 12 hours, so 10 million effective loadings can be completed within 220 days.

[0066] Example 2

[0067] like Figure 7 As shown, an embodiment of the present invention provides a linear motor driven reciprocating wheel pressure type road bridge deck fatigue test method, comprising the following steps:

[0068] S100. Install the test specimens for the simulation test at the experimental site, arrange effective temporary supports, install the experimental device on the temporary supports, and remove the temporary supports after the installation is completed;

[0069] S200. According to the preset fatigue test requirements, the functions of the experimental device are tested separately and linked to ensure the normal use of the device;

[0070] S300, starting the device in the order of increasing the ambient temperature, applying an additional load to the actuator 21, and driving the simulated vehicle-mounted component 25, and starting the experiment;

[0071] S400: During the experiment, if a short period of observation is required or the monitoring personnel temporarily leave, all actions of the experimental device shall be suspended;

[0072] S500, after the experiment is completed, the device is stopped in the order of deceleration and stop of the driving simulation vehicle-mounted component 25, unloading of the actuator 21, and cooling of the environment, and the test is terminated.

[0073] like Figure 8 As shown, step S200 is specifically as follows:

[0074] S201, disabling the loading and environmental loading functions of the actuator 21, gradually increasing the speed of the simulated vehicle-mounted component 25 from slow to fast, until the simulated vehicle-mounted component 25 reaches the designed loading speed and completes no less than ten cycles of reciprocation along the entire length of the loading track 26, and visually and sensor data are used to check the drive to ensure stable operation without abnormal noise or vibration;

[0075] S202, do not enable the environmental loading function, move the simulated vehicle-mounted component 25 to the middle span, 1 / 4 span, 3 / 4 span and two end points of the loading beam 22 in sequence, gradually increase the pressure of the actuator 21 until the test load is reached, and verify the loading system through sensor data to ensure stable operation, no unbalanced load, and no sensor failure;

[0076] S203. When conducting accelerated fatigue test on pavement, check the effect of environmental loading system, do not enable reciprocating unit 3 and actuator 21, apply hot air to the specimen at set temperature until the temperature reaches 60°C, and check the joints between enclosure, frame and ground to ensure there is no air leakage.

[0077] like Fig. 9 As shown, step S300 is specifically as follows:

[0078] S301. Raise the ambient temperature to 60°C and stabilize it for 30 minutes, ensuring that the ambient temperature fluctuation does not exceed ±5°C during this period;

[0079] S302, synchronously increase the thrust of the actuator 21 at a speed not exceeding 50 kN / min until the designed test load is reached, and hold the load for 15 minutes;

[0080] S303, start the linear motor 33 to drive the simulated vehicle-mounted component 25 to perform reciprocating motion and record the test process.

[0081] Step S400 specifically includes:

[0082] S401, when a short pause is required for observation during the test, only the speed of the simulated vehicle-mounted component 25 is reduced to 0, and the simulated vehicle-mounted component 25 is moved to the middle of the loading track 26, and the actuator and environmental load should be kept unchanged at this time;

[0083] S402, when the on-duty personnel need to leave during the test, a long pause process is executed, and the operation is performed in the order of simulating the vehicle-mounted component 25 to slow down and stop, and the actuator 21 to unload.

[0084] In step S402, if the accelerated fatigue failure test of the road pavement is carried out, the ambient temperature should be kept constant to avoid the influence of temperature stress.

[0085] like Fig.10 As shown, step S500 is specifically as follows:

[0086] S501, control the linear motor 33 to drive and decelerate until the speed of the simulated vehicle-mounted component 25 is reduced to 0, and move the simulated vehicle-mounted component 25 to the middle of the loading track 26;

[0087] S502, unloading the actuator 21 synchronously at a speed not exceeding 50 kN / min until the loading track 26 and the guide wheel of the simulated vehicle-mounted component 25 are clear;

[0088] S503, stop heating, wait for the ambient temperature to drop to room temperature or accelerate the cooling process by using a ventilation fan.

[0089] During the experiment, the normal operation and safety of the experiment must be maintained and the following standards must be implemented:

[0090] a. When the simulated vehicle-mounted component 25 is in a non-stationary state, it is not allowed to approach or touch the test device;

[0091] b. When the warning device of the environmental loading system lights up, it is not allowed to enter the enclosure;

[0092] c. When the simulated vehicle-mounted component 25 is in a stationary state but the actuator 21 is not unloaded, it is allowed to observe the specimen at a safe distance, but there should be no behavior that disturbs the actuator 21, the loading beam 22, or the specimen.

[0093] d. During the wheel pressure acceleration test, at least one person should be on duty to monitor the sensor and equipment feedback readings of the test process. When it is necessary to get close to the test system for observation during the test, at least two people should be on duty, and at least one of them should remain at a safe distance.

[0094] It will be easily understood by those skilled in the art that 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 and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device, characterized in that: include: At least two vertical reaction frames (1), each vertical reaction frame (1) comprising a pair of upright posts (11) and a crossbeam (12), wherein the crossbeam is mounted on the opposite sides of the top ends of the upright posts (11) and is fixedly connected to the two upright posts (11); A loading unit (2) disposed on the vertical reaction frame (1), the loading unit (2) comprising an actuator (21), a loading beam (22) disposed at an output end of the actuator (21), a loading vertical beam (23) disposed below the loading beam (22), a guide seat (24) disposed on a side of the column (11), and a simulated vehicle-mounted component (25); and a reciprocating motion unit (3) arranged on the vertical reaction frame (1), wherein the reciprocating motion unit (3) comprises a horizontal reaction frame (31), a motor mounting frame (32) arranged on the horizontal reaction frame (31), and a linear motor (33) arranged on the motor mounting frame (32), wherein the actuator (21) provides a vertical load for the simulated vehicle-mounted component (25), and the reciprocating motion unit (3) provides a horizontal force for the simulated vehicle-mounted component (25) to simulate the deadweight and reciprocating movement of the vehicle.

2. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to claim 1, characterized in that: At least two actuators (21) are provided at the bottom of each crossbeam (12), and are symmetrically mounted at the two ends of the crossbeam (12).

3. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue test device according to claim 2, characterized in that: Two mounting seats are provided at corresponding positions of the loading crossbeam (22) and the crossbeam (12); A pin is provided on the mounting seat, the mounting seat on the crossbeam (12) is rotationally connected to the fixed end of the actuator (21), and the mounting seat on the loading crossbeam (22) is rotationally connected to the actuator (21).

4. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to claim 3, characterized in that: The loading vertical beams (23) are used in pairs, and are parallel and span between the multiple loading horizontal beams (22), and are fixedly connected to the multiple loading horizontal beams (22); A loading track (26) is also provided at the bottom of each loading vertical beam (23) along the length direction. The loading track (26) is a straight track with a protrusion at the bottom.

5. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to claim 4, characterized in that: The guide seats (24) are provided in a group on each side of the two upright posts (11) of each vertical reaction frame (1) facing each other, and each group of guide seats (24) includes two limit plates arranged opposite to each other; The limiting plate is fixed on the upright column (11) in the vertical direction, and a gap is left between the two limiting plates as a guide channel; The width of the guide channel is the same as that of the loading crossbeam (22). Both ends of the loading crossbeam (22) are arranged in the guide channels on the two side columns (11), and the loading crossbeam (22) moves in the vertical direction in the guide channels.

6. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to any one of claims 1 to 5, characterized in that: The simulated vehicle-mounted component (25) is arranged at the bottom of the loading vertical beam (23), and comprises a vehicle body (251), a wheel axle (252) arranged at the bottom of the vehicle body (251), a loading wheel (253) arranged on the wheel axle (252), a guide wheel (254) arranged at the top of the vehicle body (251), and auxiliary wheels (255) arranged at both sides of the vehicle body (251); The vehicle body (251) is a plate-shaped structure, with a loading wheel mounting seat at the bottom, a guide wheel mounting seat at the top, and auxiliary wheel mounting seats at both sides. The wheel axle (252) is arranged on the loading wheel mounting seat, the guide wheel mounting seat, and the auxiliary wheel mounting seat.

7. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to claim 6, characterized in that: The loading wheel mounting seat is provided with at least four loading wheels arranged in a square array, the loading wheel (253) is mounted on the loading wheel mounting seat via a wheel axle (252), and the loading wheel (253) is in contact with the surface of the specimen; The guide wheel mounting seat is provided at each of the four corners of the top of the vehicle body (251), and its position in the width direction corresponds to the position of the loading track (26). The guide wheel (254) is installed on the guide wheel mounting seat through the wheel axle (252), and a groove is provided on its surface along the circumferential direction. The width of the groove is the same as the protrusion of the loading track (26), and the two form a fit. Two auxiliary wheel mounting seats are respectively arranged on both sides of the vehicle body (251), and the auxiliary wheels (255) are also mounted on the auxiliary wheel mounting seats via the wheel axles (252).

8. A linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to any one of claims 1 to 5, characterized in that: A bearing platform is also provided at the bottom end of the column (11) and on the same side as the guide seat (24); The horizontal reaction frame (31) is arranged on the bearing platform and is sandwiched between the columns (11) of each of the vertical reaction frames (1); Anti-collision blocks are provided on the inner sides of the transverse plates along the width direction at both ends of the horizontal reaction frame (31), and the anti-collision blocks are made of rubber; guide auxiliary strips are provided on the inner sides of the vertical plates along the length direction at both sides, and the auxiliary wheels (255) on both sides of the vehicle body (251) are in contact with the auxiliary strips on the inner sides of the horizontal reaction frame (31).

9. The linear motor driven reciprocating wheel pressure type road and bridge deck fatigue testing device according to claim 8, characterized in that: The motor mounting frame (32) spans the horizontal reaction frame (31) along the length direction of the horizontal reaction frame (31), and its two ends are fixed to the horizontal plate of the horizontal reaction frame (31) along the width direction, and a hollow is provided in the center part of the fixed position, and the two ends of the hollow position are connected to serve as a mounting position; The linear motor (33) is installed in the motor installation position of the motor installation frame (32), and its output end is connected to the two ends of the vehicle body (251), and the connection point is also connected by rotation.

10. A linear motor driven reciprocating wheel pressure type road bridge deck fatigue test method, implemented by using a linear motor driven reciprocating wheel pressure type road bridge deck fatigue test device as described in any one of claims 1 to 9, characterized in that: include: S100. Install the test specimens for the simulation test at the experimental site, arrange effective temporary supports, install the experimental device on the temporary supports, and remove the temporary supports after the installation is completed; S200. According to the preset fatigue test requirements, the functions of the experimental device are tested separately and linked to ensure the normal use of the device; S300, starting the device in the order of increasing the ambient temperature, applying an additional load to the actuator (21), and driving the simulated vehicle-mounted component (25), and starting the experiment; S400: During the experiment, if a short period of observation is required or the monitoring personnel temporarily leave, all actions of the experimental device shall be suspended; S500, after the experiment is completed, the device is stopped in the order of decelerating and stopping the driving simulation vehicle-mounted component (25), unloading the actuator (21), and cooling the environment, thereby terminating the test.

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