横向地震作用下车辆?板式无砟轨道系统随机振动分析

地震波本质为非平稳随机过程。为了准确分析地震波对车辆?轨道系统非线性振动行为及动力可靠度的影响,基于车辆?轨道动力相互作用模型、轨道不平顺概率模型和概率密度演化方程,建立考虑轨道随机不平顺作用的横向地震?车辆?轨道系统随机分析及可靠度计算模型。以地震波演化功率谱模型为例,峰值加速度取为1.96 m/s2,对地震和轨道不平顺联合作用下的车辆?轨道系统随机响应进行数值分析。研究结果表明:当考虑轨道不平顺和地震波的联合作用时,车体横向加速度和轮轨横向力较仅考虑地震波作用下的系统响应增大约10.92%和24.97%;轨道随机不平顺与地震随机波的耦合将进一步增大结构动力响应的离散性,故而开展地震和轨道随机不平顺的联合分析是必要的。

Vehicle-ballastless slab track stochastic analysis subjected to lateral earthquakes

The seismic waves are non-stationary random processes in essence.Based on the vehicle-track dynamic interaction model,track irregularity probabilistic model and probability density evolution model,a stochastic analysis and reliability assessment model for vehicle-track coupled system subjected to earthquakes and track random irregularities was proposed to accurately analyze the influence of stochastic seismic waves on the nonlinear vibrational behaviors and dynamic reliability of vehicle-track systems.Set the evolutionary power spectrum model of seismic waves and the peak value of acceleration 1.96 m/s2 as examples,a numerical analysis was conducted for the random response analysis of vehicle-track systems subjected to earthquakes and track irregularities.Summarily it can be concluded that the vehicle lateral acceleration and wheel-rail lateral force have been increased by about 10.92%and 24.97%if track irregularities are also considered as excitation except for the lateral earthquakes,besides,the coupling effects of the track random irregularities and lateral earthquakes will further increase the dispersion of structural responses.It is therefore a necessity to conduct the dynamics analysis where earthquakes and track random irregularities should be jointly considered.