| High-speed railway plays a very important role in promoting national economic development and national construction.With the large-scale construction and operation of high-speed railways,enable trains to run smoothly and safely,the requirements for fastener systems in high-speed railway tracks The higher the future,the function of the fastener system is to buckle the rail and the foundation under the rail.The fastener is the most frequent part of the rail structure for replacement and maintenance,and the elastic strip is the fastener as the key component to achieve the function of the fastener.The most frequent part of replacement and maintenance in the system.The spring bar provides buckling pressure through its own deformation.During the service of the fastener,the fastener elastic strip repeatedly bears the load from the rail.Fatigue damage is the main form of fastener elastic strip failure.This article is aimed at the WJ-7 fastener elastic strip commonly used in domestic high-speed railways.The finite element simulation and fatigue test are carried out to analyze the fatigue properties of the fastener elastic strip.The paper uses ABAQSU finite element software to simulate and analyze the fastener system,and analyzes the stress change of the fastener elastic strip under different bolt preloads.It is found that the stress value at the arc at the rear end of the fastener elastic strip is large.When the preload force reaches 25 k N,the fastener elastic strip is in a more reasonable working state;by using FE-SAFE fatigue analysis software,it is found that the arc at the rear end of the fastener elastic strip is still the most prone to fatigue fracture position under the action of fatigue load.The WJ-7 fastener under normal working conditions bears more tensile and torsional loads.Therefore,the 60Si2 Mn A steel used in the WJ-7 fastener elastic strip was subjected to the tensile and torsional fatigue test on the MTS809 electro-hydraulic servo fatigue test system.The relationship between stress and fatigue life is recorded,and the S-N curve of 60Si2 Mn A steel is obtained under the tensile and torsional cyclic load,and the S-N curve of the material is fitted with a power function formula;different tensile and torsional working conditions are recorded Under the stress-strain hysteresis curve of the 60Si2 Mn A sample,when the stress amplitude is constant,the strain amplitude continues to increase as the number of cycles increases;using an electron microscope scanning microscope,the fracture of the sample is low to high Scanned and analyzed the three typical fatigue fracture areas.The strain electrical measurement method was used to measure the stress value at the most dangerous position from the fastener elastic strip to fatigue failure under cyclic loading. |
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