52 results about "Bending fatigue test" patented technology

The invention provides a metal plate bending fatigue testing device, and relates to the technical field of bending fatigue testing assistion.The metal plate bending fatigue testing device comprises a portal frame, a testing device support, a testing pressure applying assembly and two bearing assemblies, and the testing pressure applying assembly comprises a hydraulic push rod, a T-shaped plate, a rotating air cylinder, an adjustable pressure applying piece and a roller assembly; the two bearing assemblies each comprise a supporting round rod, a transverse rod base and a vertical plate base, two round rollers are arranged between the two supporting round rods, and ratchet wheel assemblies are arranged at the two ends of the two round rollers; according to the technical scheme, a T-shaped plate is controlled by a hydraulic push rod to drive an adjustable pressure applying piece and a roller assembly to move towards the bottom, and a rotary air cylinder drives the adjustable pressure applying piece to drive the roller assembly to rotate, so that a sample plate is supported by a supporting round rod and a round roller, and the roller assembly applies pressure when rolling at the center of the top of the sample plate; the effect of expanding the bending angle of the sample plate is achieved, and the basic requirement for simulating the working state is provided for data acquisition in the subsequent sample plate fatigue test.

The invention relates to the technical field of mechanical fatigue testing, in particular to rotary bending fatigue testing equipment for a rotor shaft, which comprises a base, a rotary driving module, a loading module, a dynamic balance module, a crack monitoring module and an adjusting module, and is characterized in that the rotary driving module drives the rotor shaft to rotate through a belt transmission assembly; the loading module adopts a lever type force reversing mechanism to realize accurate bending moment loading; the dynamic balance module automatically counteracts eccentric vibration through a free disc and a symmetrical bearing seat; the crack monitoring module captures vibration abnormity and internal crack initiation in real time; and the adjusting module is automatically adapted to different shaft lengths by driving a threaded screw rod through a motor. Anti-slip lines are arranged on the inner sides of the clamps at the two ends to ensure stable clamping; the levers are symmetrically arranged and matched with the locking nuts, so that switching of translation force or bending force applied by the levers is facilitated, the equipment realizes high-precision and full-period fatigue test, and the device is suitable for reliability evaluation of key rotor parts of aero-engines and steam turbines.

This disclosure relates to the field of fatigue testing, specifically to a bending fatigue testing apparatus and a bending fatigue testing system. The bending fatigue testing apparatus includes a test bench, a fixing fixture, and a loading fixture. The fixing fixture has two limiting ends spaced apart along a first direction, and the two limiting ends are connected to the test bench. The fixing fixture is movable relative to the test bench along a second direction to adjust the distance between the fixing fixture and the test bench. The test bench and the loading fixture are arranged sequentially along a third direction, and the loading fixture is movably arranged in the second direction, used to move the test piece along the second direction. The first direction is perpendicular to the second direction, and the third direction is perpendicular to both the first and second directions. By implementing the bending fatigue testing apparatus and system of the exemplary embodiments of this disclosure, cantilever bending fatigue tests can be performed on test pieces to test their bending fatigue performance.

The utility model belongs to the technical field of metal material fatigue tests, and particularly relates to a testing device for diaphragm compressor research and development, which comprises a support and a testing assembly, the support is a rectangular frame-shaped support, clamping assemblies are arranged in the middle of the inner side of a left frame and the middle of the inner side of a right frame of the support, and the testing assembly comprises a hydraulic cylinder and a testing mold. The fixed end of the hydraulic cylinder is connected with the inner side of an upper side frame of the support, the telescopic end of the hydraulic cylinder is connected with the upper side of the test mold, the test mold comprises an upper mold, a lower mold and a connecting plate, and the connecting plate is fixedly connected with the rear sides of the upper mold and the lower mold. And a periodic load test is carried out, and the stress state of the compressor in actual service is simulated to the greatest extent, so that the data of the symmetric bending fatigue test of the metal diaphragm is true and credible.

The application discloses a kind of asphalt mixture fatigue life prediction methods, comprising the following steps: S1, making the standard test piece of asphalt mixture;S2, the three-point bending fatigue test of asphalt mixture under different stress levels is carried out to the standard test piece made under the setting parameter;S3, according to the stress-strain hysteresis curve of asphalt mixture is fitted to test data;S4, the accuracy of the stress-strain hysteresis curve obtained is verified;S5, based on the hysteresis curve, the fatigue damage variable of asphalt mixture is constructed;S6, the fatigue life prediction model of asphalt mixture is constructed.The method of the application avoids the defect that the relative change rate of dissipation energy is the discrete index data of prediction fatigue life, so as to improve the prediction accuracy of asphalt mixture fatigue life, the model construction step is less, form is simple, and has higher practical value.

The application discloses a kind of based on initial modulus index asphalt mixture fatigue life prediction method, the present application includes the following steps: S1, the standard test piece of asphalt mixture is made;S2, the three-point bending fatigue test of asphalt mixture under different stress levels is carried out to the standard test piece made under setting parameter;S3, according to test data fitting asphalt mixture stress strain hysteresis curve;S4, based on the stress strain hysteresis curve obtains the initial modulus and failure modulus of asphalt mixture;S5, based on the initial modulus and failure modulus described above constructs the fatigue damage factor model of asphalt mixture based on initial modulus;S6, based on the fatigue damage factor model constructed predicts the fatigue life of asphalt mixture in use.The present application is more reasonable by introducing failure modulus and constructing damage factor model, so that the residual life of asphalt mixture can be more accurately and quickly predicted.

This invention provides a high-temperature three-point bending ultrasonic fatigue testing device and its usage method, which can be used to conduct high-temperature and ultra-high-temperature three-point bending fatigue tests on materials. This invention overcomes the limitation of traditional three-point bending ultrasonic fatigue tests, which can only be performed at room temperature, bringing a novel fatigue testing method. Furthermore, the combined fixture device adopts a modular design, making it simple to process and operate, and easy to replace.

The utility model discloses a horizontal high-speed rotating bending fatigue testing device, which belongs to the technical field of bending fatigue testing equipment and comprises a rotating bending fatigue testing machine body and a moving mechanism fixedly mounted outside the rotating bending fatigue testing machine body. The moving mechanism comprises a U-shaped shell fixedly installed on the outer wall of the rotary bending fatigue testing machine body, a U-shaped frame is slidably installed in the U-shaped shell, four supporting columns distributed in a matrix mode are fixedly connected to the bottom of the U-shaped frame, rolling wheels are rotatably installed at the lower ends of the supporting columns, and the rolling wheels are movably installed on the U-shaped frame. A screw rod is rotationally mounted on one side of the interior of the U-shaped shell, and the U-shaped frame is connected to the screw rod in a sleeving manner and is in threaded connection with the screw rod; through the arrangement of the moving mechanism, the moving mechanism can be additionally arranged outside the rotating bending fatigue testing machine body, the rotating bending fatigue testing machine can be conveniently moved, manual carrying is not needed, and time and labor are saved.

The invention belongs to the technical field of material fatigue strength testing, and particularly relates to a composite material bending fatigue testing machine and method.The composite material bending fatigue testing machine comprises a frame body, a first linear mover and a second linear mover are arranged on the front side wall of the frame body, and the moving path of the first linear mover is located on the lower left portion of the moving path of the second linear mover; the moving path of the first linear mover is transverse, the moving path of the second linear mover is longitudinal, a rotating disc is arranged on the front side wall of the frame body through a rotating device, the rotating disc is located over the second linear mover, and a plurality of positioning holes are formed in the position, away from the center of the rotating disc, of the rotating disc. The distance between each positioning hole and the center of the rotating disc is not equal, and the face, back on to the front side wall of the frame body, of the second linear mover is rotationally connected with one end of a connecting rod, and the problem of how to achieve displacement adjustment in a fatigue test through a mechanical means is solved.

The invention discloses a load loading device of a rope belt bending fatigue testing machine and the testing machine, the load loading device comprises a base, a slide rail and an adjusting loading device, the base is provided with the adjusting loading device and the slide rail, the slide rail is slidably provided with two test wheels which are staggered up and down, and the two test wheels are used for sleeving a test rope belt; the adjusting and loading device comprises a mounting stand column, a telescopic rod and a vertical displacement mechanism, the mounting stand column is mounted on the rear side of the sliding rail, the vertical displacement mechanism is arranged on the mounting stand column, the moving end of the vertical displacement mechanism is used for being connected with the telescopic rod and driving the telescopic rod to vertically move, and the telescopic end of the telescopic rod is hinged to one ends of two driving rods; the other ends of the two driving rods are hinged to the side ends, extending out of the sliding rail, of the center shafts of the two test wheels respectively, and the telescopic rod is used for extending forwards or retracting backwards and driving the two test wheels to get away from or get close to each other in the vertical direction. According to the invention, the telescopic rod can be controlled to stretch out and draw back and drive the two test wheels to be far away from or close to each other in the vertical direction, so that tension adjustment of the test rope belt is realized, and the loading efficiency can be improved.

The application discloses a kind of asphalt pavement asphalt mixture layer fatigue life prediction method, belong to data processing technical field, including preparation asphalt pavement structure fatigue life calculation layer asphalt mixture sample;Using beam four-point bending testing machine to carry out bending fatigue test to asphalt mixture, test the fatigue life of asphalt mixture under different test temperatures and strain levels, in combination with fatigue life test results, take the average of each test temperature and strain level combination, deduce fatigue life prediction model based on different each type asphalt mixture;According to the parameters of fatigue life prediction model based on different types of asphalt mixture, determine asphalt mixture layer fatigue cracking life model.The application constructs the fatigue life prediction model of pavement structure asphalt layer based on different types of asphalt mixture, and can realize the fatigue life prediction of asphalt pavement asphalt mixture layer for more than 30 years, is favorable for the accurate design and maintenance of long-life asphalt pavement structure.

A method for measuring the bending fatigue life of a forged aluminum alloy hub belongs to the technical field of automobile hub manufacturing, and is characterized by comprising the following steps: 1) under the condition of not considering the influence of other external forces, according to a hub bending fatigue test, only the acting force of a bending load on a hub connecting rod; and (2) according to the fatigue damage accumulation theory, the maximum stress Smax and the minimum stress Smin of the forged aluminum alloy hub under the action of the bending moment, the average stress S and the fatigue damage D of the hub are calculated, and the relation among the average stress S, the fatigue damage D and the bending fatigue life N of the forged aluminum alloy hub is directly designed. The method has the advantages that the relationship with the bending fatigue life of the hub can be determined through the average stress and fatigue damage of the hub, the fatigue life of the hub is rapidly measured, and the actual experiment cost is saved.

This invention relates to the field of material fatigue testing technology, and more particularly to a high-temperature rotary bending fatigue testing device capable of simulating different salt spray environments. Addressing the problem of existing equipment providing only a single environmental simulation, the high-temperature rotary bending fatigue testing device proposed in this invention includes an environmental cabinet with a shock-absorbing wooden block at the top; it also includes an environmental simulation mechanism, a salt spray supply and control mechanism, and a rotary bending loading mechanism. The environmental simulation mechanism is located on top of the shock-absorbing wooden block; the salt spray supply and control mechanism is located inside the environmental cabinet and communicates with the interior of the environmental simulation mechanism, used to control the concentration and flow rate of the salt spray supplied to the environmental simulation mechanism; the rotary bending loading mechanism is located on top of the shock-absorbing wooden block and coaxially connected to the environmental simulation mechanism, used for rotary bending of the test specimen. The high-temperature rotary bending fatigue testing device of this invention can closely simulate real service environments.

The invention provides a bending-torsional fatigue testing device, relates to the technical field of bending-torsional fatigue testing, and is used for solving the technical problem that a rotary bending fatigue testing device is complex in structure. The bending-torsional fatigue testing device comprises a base, two loading assemblies and a tested piece, and the base is provided with two arc-shaped rails; the two arc-shaped rails are symmetrically arranged on the base in the first direction. The two loading assemblies are movably connected with the two arc-shaped rails respectively, and one loading assembly is connected with one arc-shaped rail; each loading assembly comprises two loading pieces, and the two loading pieces move along the corresponding arc-shaped rails in the direction close to each other or away from each other; the tested piece is located between the two loading assemblies, and each loading piece is in direct contact with the tested piece. The testing device is used for detecting and evaluating the bending-torsional fatigue life of the tested piece, and the testing device is simple in structure.

The application discloses a flexible beam bending fatigue test load monitoring method of unmanned helicopter, which comprises the following steps: pasting strain gauges on a test piece and a test piece fixing joint, checking the effectiveness of the strain gauges; calibrating all specified sections of the test piece and the test piece fixing joint; performing load debugging before the test to obtain load values of monitoring sections meeting test task requirements; performing a flexible beam bending fatigue test, monitoring the flexible beam bending load in the test process by using a strain monitoring load mode; and performing test monitoring by means of test load drop and upgrade according to strain output load values and edgewise forces on the test piece fixing joint after all the strain gauges on the test piece are damaged. The technical scheme of the application solves the problems of prolonged test period, low test efficiency, increased labor cost, wasted test resources, and difficulty in completing the test task within a specified time.

The invention belongs to the technical field of ferrule joint detection, and particularly relates to a ferrule joint bending fatigue test device which comprises a base, a U-shaped seat is fixed to the top of the base, a transverse plate is slidably mounted in the U-shaped seat, a box is fixed to the top of the transverse plate, and a counterweight plate is slidably inserted into the box. The box body is provided with a limiting assembly used for limiting the balance weight plate, two connecting blocks are symmetrically fixed to the top of the box body, and clamping holes are formed in the side walls of the two connecting blocks. Through the arrangement of the base, the U-shaped seat, the transverse plate, the box body, the counterweight plate, a limiting assembly, a connecting block, a clamping hole, a clamping assembly, an air cylinder, an impact block and a clamping assembly, a to-be-detected clamping sleeve joint can be conveniently and rapidly clamped and fixed, and reciprocating pressure application operation can be performed on the to-be-detected clamping sleeve joint. And the magnitude of acting force applied to the clamping sleeve connector can be conveniently adjusted, so that the overall using effect is good.

The invention discloses a dexterous hand bionic finger bending fatigue testing machine and a testing method thereof, and relates to the technical field of bionic finger tests.The dexterous hand bionic finger bending fatigue testing machine comprises a bottom box, a platform plate is fixedly connected to the top of the bottom box, a mounting interface base is fixedly connected to the upper surface of the platform plate, a bionic dexterous hand is inserted into the mounting interface base, and a plurality of lifting boxes are slidably connected into the bottom box; balancing weights are detachably stacked in the lifting boxes, and stabilizing wheels corresponding to the lifting boxes are rotationally connected to the platform plate. The bending fatigue test of the bionic dexterous hand can be performed in different degrees by increasing different numbers of balancing weights, so that fingers of the bionic dexterous hand can be bent and circulated under different external loads, light-load life verification can be performed, heavy-load accelerated fatigue test can also be performed, and the application range is wider; different bionic dexterous hands have different finger rigidities, sizes and materials, and required test loads are different; the balance weight can be increased or decreased, so that the device can adapt to multiple models and multiple schemes without replacing the main mechanism, and the universality is improved.

The invention discloses a temperature control device and a temperature control method for a rotary bending fatigue test. The rotating bending fatigue test temperature control device comprises a test platform, the upper surface of the test platform is fixedly connected with a testing machine, the testing machine is provided with a voltage transmission module, the voltage transmission module is wirelessly connected with a voltage reduction device, the voltage reduction device is connected with a temperature control device through a second compensation wire, and the temperature control device is connected with a resistance furnace through a resistance furnace control wire. A through hole is formed in the resistance furnace, the resistance furnace is connected to the testing machine in a sleeving mode, and according to the temperature control method for the rotary bending fatigue test, the temperature is controlled through the temperature control device for the rotary bending fatigue test. The thermocouple can be in direct contact with the sample, and the problems that a rotating bending test thermocouple cannot be in contact with the sample, and accurate temperature control on the test sample is difficult are solved.

The method for predicting the service life of the coiled tubing under the cooperation of plasticity and damage is characterized in that the fatigue service life and the strain amplitude under the specific curvature radius are obtained through a full-size bending fatigue test, and the fatigue service life and the strain amplitude are substituted into a Manson-Coffin model to invert an unknown coefficient; the method comprises the following steps: determining mechanical parameters of a material in combination with a uniaxial tensile test, constructing a finite element mechanical model, carrying out finite element simulation on bending working conditions of a damaged coiled tubing on a roller and a guider, extracting strain amplitudes, and further establishing strain amplitude calculation models under different working conditions by adopting a Levenberg-Marquardt algorithm; coupling the model with a Manson-Coffin equation, and respectively constructing fatigue life prediction models of the roller and the guider; and on the basis of the Miner theory, three times of bending cycles with different curvatures in one trip are regarded as complete load cycles, an accumulated damage value is calculated, a correction coefficient is determined through low-cycle fatigue finite element simulation, a calculation model of the number of remaining trip times is established, and quantitative prediction of the remaining life is achieved. The method is suitable for the technical field of petroleum and natural gas drilling engineering.

The utility model relates to the field of gear bending fatigue tests, and discloses a double-tooth loading test fixture for gear bending fatigue tests, which comprises a U-shaped supporting seat, a fixture body is arranged on the upper surface of the U-shaped supporting seat, a fixing component is arranged in the U-shaped supporting seat, a positioning component is arranged in the fixture body, and the positioning component is arranged on the upper surface of the U-shaped supporting seat. The fixing assembly comprises a supporting shaft, the outer wall of the supporting shaft is sleeved with a first gasket, the outer wall of the supporting shaft is sleeved with a gear sample, the outer wall of the supporting shaft is sleeved with a second gasket, the front end of the outer wall of the supporting shaft is provided with a threaded groove, and the outer wall of the threaded groove is in threaded connection with a locking nut. According to the gear sample clamping and positioning device, through cooperation of the fixing assemblies, the gear sample can be supported, longitudinal deviation of the gear sample can be prevented, the gear sample can be clamped and positioned in the front-back direction, deviation of the gear sample can be effectively prevented, and the stability of the gear sample in the testing process is improved.

The invention discloses a material fatigue testing machine for special equipment production, and relates to the technical field of testing machines, the material fatigue testing machine comprises a base, a vertical rod is fixedly mounted on the base, a top plate is fixedly mounted on the vertical rod, a plurality of test rods are mounted on the top plate, and the test rods are L-shaped; a first sliding plate is arranged on the base, and a servo motor is fixedly installed on the first sliding plate. According to the material fatigue testing machine for special equipment production provided by the invention, the state of the second disc can be switched through the forward and reverse conversion connecting mechanism, so that the second disc rotates or translates, and the pressing plate moves in the rotating process, so that a pressure fatigue test is performed on a spring; and when the second disc translates, the spring is subjected to a bending fatigue test, so that a pressure test and a bending test can be carried out in the test, instrument transfer of the spring is avoided, and the test steps and time are saved.

The application discloses a simply supported beam bending fatigue testing machine horizontal loading system, which comprises a fixed loading end and a movable loading end, the center line of the movable loading end is in the same level with the center line of the fixed loading end; the fixed loading end is fixedly connected with a workbench surface, the overall structure comprises a first rotating shaft system composed of a first precision mechanical main shaft and a precision electric main shaft, and a first loading shaft system rotating along the axis of the first precision mechanical main shaft; the movable loading end is horizontally slidably connected with the workbench surface through a guide rail, the overall structure comprises a second rotating shaft system composed of a second precision mechanical main shaft, and a second loading shaft system rotating along the axis of the second precision mechanical main shaft; a sample to be tested is clamped between the fixed loading end and the movable loading end. The application makes the loading force and the gravity of the main shaft system perpendicular to each other, eliminates the influence of the gravity of the main shaft system on the loading force and the test result, overcomes the defects of the original vertical loading system, and makes the test result more accurate and reliable.

The application discloses a kind of laser cladding repair axle class part fatigue life prediction method and system, comprising: obtaining each test piece microdefect feature, the heterogeneous structure feature of the microstructure of cladding layer-heat affected zone-substrate, carry out rotating bending fatigue test, obtain the rotating bending fatigue life data corresponding to microdefect feature, heterogeneous structure feature, and establish the fatigue life label corresponding to data;Establish the initial data set including cladding layer microdefect feature parameter, heterogeneous structure feature parameter and axle fatigue life data;And the data set is pretreated and reduced dimension processing;Establish feature extraction model, adopt random forest regression model to carry out feature importance quantification, identify key feature;The fatigue life prediction model of XGBoost algorithm is constructed, the feature parameter of the high independence of microdefect and heterogeneous structure is obtained, and the key feature parameter and weight are screened out, to carry out residual fatigue life prediction based on fracture mechanics framework.

The utility model belongs to the field of testing machines, and relates to detection of trailer axles, in particular to a two-channel vertical bending fatigue testing machine for trailer axles, which comprises a portal frame, the portal frame comprises a cross beam, a sliding rail is fixedly connected above the cross beam, the sliding rail is slidably connected with a sliding block, a hydraulic oil cylinder seat is fixedly connected above the sliding block, and the hydraulic oil cylinder seat is connected with a hydraulic oil cylinder. The hydraulic cylinder base is fixedly connected with a small hydraulic oil cylinder, the small hydraulic oil cylinder comprises a telescopic rod penetrating through the hydraulic oil cylinder base, the telescopic rod is fixedly connected with a supporting plate, the supporting plate is arranged above the hydraulic oil cylinder base, an upper positioning plate is arranged above the supporting plate, and the telescopic rod penetrates through the upper positioning plate; the upper positioning plate is fixedly connected with a supporting rod, the lower end of the supporting rod is fixedly connected with a lower positioning plate, the lower positioning plate is arranged below the cross beam, and the lower side of the lower positioning plate is fixedly connected with two servo actuators.

The invention relates to the technical field of durability detection of auxetic structures, in particular to a bending fatigue testing machine for durability detection of auxetic structures, which comprises a testing outer box shell, two sides of the testing outer box shell can be opened, a fixed disc is fixedly mounted on the inner side of the testing outer box shell, and a twisting disc capable of rotating by power is mounted at the axis of the fixed disc. Two testing mechanisms are arranged in the testing outer box shell and installed on the outer side of the twisting disc and the outer side of the fixing disc respectively. The clamping assemblies on the inner side cannot be separated through the four clamping shafts on the outer sides of the clamping assemblies, when the side plates are controlled to move relative to the main frame, pulling force is applied to the clamping assemblies on the sides, closest to the fixing disc, of the clamping shafts through the stop rods, and the clamping assemblies are clamped by controlling the clamping shafts to move relative to the clamping assemblies and controlling the stop rods to move relative to the clamping assemblies. After the clamping shafts move, pulling force is applied to different layers of the clamping assemblies through the stop levers, different point positions of the material can be detected, and stress concentration of the material structure is effectively prevented.

The invention discloses a clamp device and a test method suitable for a bending fatigue test under displacement control of a T-shaped joint. Belongs to the field of welding structure fatigue performance testing. Comprising an upper clamp, a lower clamp and a plurality of bolts, a cylindrical structure arranged at the bottom of the upper clamp is in contact with an upper plate positioned in the middle of the T-shaped joint test piece, and the center of the cylindrical structure is offset from the central axis of the T-shaped joint test piece, so that the upper clamp forms eccentric loading in the process of moving downwards along with the hydraulic wedge block, and the lower clamp is rigidly connected with the T-shaped joint test piece through a plurality of bolts. Through reasonable structural arrangement, the upper clamp can accurately transmit displacement; meanwhile, the real stress mode of the test piece under the bending load is ensured through the high-rigidity constraint of the lower clamp. The objective of the invention is to improve the loading stability and the displacement control precision and ensure the true and reliable stress distribution, so that the accuracy and repeatability of the bending fatigue test of the T-shaped welding structure are obviously improved.

The utility model relates to the technical field of cable testing, in particular to a cable bending fatigue testing structure. A cable bending fatigue test structure comprises a rack; the first supporting block and the second supporting block are arranged on the rack in a spaced mode, the first supporting block and the second supporting block are arranged in a mirror symmetry mode, and the opposite sides of the first supporting block and the second supporting block are each provided with an arc-shaped face; and one side of the change gear is rotationally connected to the rack through a rotating shaft. The beneficial effects of the utility model are that the change gear is sleeved with the test cable, one end of the test cable is bent along the arc-shaped surface, the bending test in the other direction is completed through the steering part, and the cable is pulled by combining the winding of the winding part on the cable, so that all sections of the cable can be subjected to comprehensive bending test; the bending fatigue test of the whole section of cable is realized, so that the actual fatigue condition of the cable in the use process is reflected more truly.

The present application relates to the field of civil engineering material simulation technology, and provides a kind of track slab SCC multi-phase mesoscopic fatigue damage near-field dynamics simulation method, comprising: according to four-point bending fatigue test to establish two-dimensional mesoscopic near-field dynamics model;Meshless discretization is carried out to the model;Define the material parameters of cement mortar, coarse aggregate and interface transition zone;Set boundary conditions;Random polygon aggregate is generated by taking and placing method to simulate mesoscopic heterogeneous structure;Mark particle and key type;Apply cyclic loading;Damage evolution calculation is carried out based on the maximum key elongation criterion and fatigue life model;Finally, the calculation is terminated by particle damage index judgment.The present application can realize the accurate simulation of the whole process from crack initiation to expansion of CRTS III type track slab self-compacting concrete, provide effective numerical analysis tool for revealing the influence mechanism of aggregate distribution randomness on fatigue performance, and thus provide theoretical basis for track structure durability design and maintenance.

This invention discloses a deflection measuring device for axial bending fatigue testing, relating to the field of road engineering technology. It includes a base, with the lower end of a connecting rod fixedly connected to the base, and the upper end of the connecting rod fixedly connected to a disc clamp. The disc clamp is threadedly connected to a deflection measuring component. It also includes an upper loading head and a lower loading head, with the working ends of the upper and lower loading heads positioned opposite each other. The non-working ends of both the upper and lower loading heads are fixedly connected to a loading device, and the interior of the lower loading head mates with the deflection measuring component. This invention overcomes the measurement error problem in current axial bending fatigue tests, simplifies the testing process, and allows for more accurate and efficient evaluation of the fatigue characteristics of the specimen.