车桥耦合振动中2种轮轨接触模型的比较分析

将车桥耦合系统分为车辆和桥梁2个系统并分别给出二者的振动方程,采用迭代解法对方程进行求解,分析轮轨之间弹性接触和密贴接触对车桥系统动力分析结果的影响。结果表明:密贴接触模型取的时间步长比弹性接触模型取的时间步长大,密贴接触模型迭代时间步长为0.001 s时收敛,而弹性接触模型迭代时间步长要0.000 1 s才收敛。在同样时间步长0.000 1 s条件下,弹性接触模型的收敛迭代次数为9次,而密贴接触模型的收敛迭代次数为4次;在计算桥梁的动力响应时,弹性接触模型和密贴接触模型的计算结果比较接近,也和实测值接近,但密贴接触的计算工作量较小,收敛快;而在计算列车的竖向加速度、轮重减载率和脱轨系数时,弹性接触模型的计算结果比密贴接触模型的计算结果大。分析认为用弹性接触模型比较符合实际。

Contrast Analysis of Two Wheel-Rail Contact Models in the Coupling Vibration of Vehicle-Bridge System

Vehicle-bridge coupling system is divided into vehicle and bridge systems and the vibration equations for both systems are given.The equations are solved by iterative method and the influence on the dynamical analysis result of vehicle-bridge system by elastic contact model or tight contact model between wheel and rail is analyzed.The results indicate that the convergence time step of tight contact model is 0.001 s,which is longer than that of elastic contact model 0.000 1 s.At the same time step 0.000 1 s,the iteration number of tight contact model is 4 to convergence,and that of elastic contact model is 9.In calculating bridge dynamic response,the results of the two models are relatively close,and close to the measured values.In comparison,the tight contact calculation quantity is smaller,and it could rapidly get to convergence.However,in the analysis of vertical train acceleration,the load decrement rate of wheel weight and derailment coefficient,the result of elastic contact model is greater than that of tight contact model.Analysis show that elastic contact model accords better with facts.