Study On The Influence And Detection Method Of Steel Spring Failure On The Dynamic Performance Of Floating Slab Track

As the main vibration reducing and isolation device in the steel spring floating slab track,steel spring vibration isolator is prone to failure under the action of reciprocating train load.The failure of steel spring vibration isolator will reduce the uniformity and integrity of the foundation stiffness,and further threaten the structural stability and riding stability.At present,there are few researches on the failure identification of steel spring vibration isolator in spring-steel floating slab track,Therefore,this dissertation establishes the vehicle-steel spring floating slab track coupling dynamic model with steel spring vibration isolator failure and analyzes the dynamic performance of spring-steel floating slab track after the failure of steel spring vibration isolator,the simulation data of measuring points are extracted to research the failure identification index of steel spring vibration isolator by using a variety of signal processing methods.The main research work and conclusions in this dissertation are as follows:(1)The vehicle-floating slab track is established based on the theory of vehicle-track coupling dynamics and ABAQUS.The rationality and reliability of the model are verified for the further research.(2)The sensitivity of train vertical acceleration to the failure of single or multiple steel spring vibration isolators is low;When a single steel spring vibration isolator fails,the failure of the steel spring vibration isolator at the end of the slab has more influence on the vibration response of the track structure than that at the middle of the slab under the train load;When multiple steel spring vibration isolators fail,the maximum vertical displacement of rail and plate increases significantly,which has a great influence on the stability of steel spring floating slab.(3)Based on the vertical acceleration of the detection points before and after the failure of the steel spring vibration isolator,the value of vibration transmissibility between the detection points is calculated.By comparing the maximum value,the results show that the maximum value of vibration transmissibility is always greater than 1 before the failure of steel spring vibration isolator,and less than 1 after the failure,which proves that the value of vibration transmissibility can be used as the failure identification index.(4)By using the phase space reconstruction,the one-dimensional vector of vibration transmissibility is constructed as a two-dimensional matrix,and its singular value entropy is calculated.The results show that the value of singular value entropy is not less than 2 before the failure of steel spring vibration isolator,and less than 2 after the failure,which proves that the value of singular value entropy can also be used as the failure identification index.