Seismic Safety Analysis Of Train Based On High-speed Operating Train-bridge Coupling Model

Since the construction of high-speed railway in China,the speed of train has been increasing day by day,as well as the share of bridges in the total rail line has been growing gradually.Thus,the probability of the trains operating on bridges under earthquake ground motion greatly improves,which threatens the running safety of the trains.To reduce the damage caused by earthquake to the safety of railway,many countries and districts around the world carry out the study on the earthquake alarm system and the seismic urgent handling system for railway transport.The analysis of dynamic responses of high-speed railway train-bridge coupling system and the seismic safety analysis of train are one of the important ways to obtain the alarm threshold,which has great significance on keeping the running safety of train.Based on the introduction of the current states of the related research,many research works has been carried out in this paper and the main research works are as follows:1.The typical simply-supported girder bridge and high-speed train were taken as the objects of the research,the high-speed operating train-bridge coupling system was set up and the train operation was simulated based on parametric-design-language developed in this paper which could control the element birth and death of train model element.In order to study the train running safety,the train,which is commonly used in our country and has two suspensions,four axles,was taken as the research object,the train model which considers the wheel-rail contact was set up.2.Based on large-scale structural analysis software,seismic responses of the train-bridge coupling system under typical ground motions were calculated and compared with the computational results of single bridge model and the train-bridge coupling model which does not consider train operation.The necessity of the model established in this paper in the analysis of train running safety and the computation of seismic urgent handling threshold of high-speed railway system was illustrated.3.Typical track irregularity was selected,and track irregularity excitation was generated by numerical simulation of the power spectrum density function based on trigonometric series method.The acceleration time histories of train-bridge coupling system under typical ground motions and the track irregularity were taken as the external excitations of the train model,and the running safety of train was analyzed based on the parameters of security: the derailment coefficients,rates of wheel load reduction and lateral wheel interaction forces.4.The parameters of running safety of different trains such as ICE3,CRH2 were computed and analyzed under the excitation of ground motions and track irregularity.Typical track spectrums were compared based on the power spectrum density,and the dynamic responses of train were computed under the excitations of different track irregularities.