基于代理模型的无砟轨道模拟方法及其在车-线-桥分析中的应用

Simulation method and its application in dynamic analysis of vehicle-track-bridge system with ballastless track based on surrogate model

为解决轨道结构有限元建模的复杂性和计算效率低等问题,针对桥上双块式无砟轨道结构,该文提出一种新型的无砟轨道简化方法:K-G离散点支承梁模型。利用自适应Kriging代理模型,建立了无砟轨道简化模型与精细化模型响应间的对应关系,采用遗传算法(GA)确定了简化模型的结构参数,并与精细化模型进行对比,验证了简化模型的准确性。最后,将该无砟轨道简化模拟方法应用于某大跨铁路拱桥,进行车-线-桥耦合分析,结果表明:K-G离散点支承梁模型的竖向位移响应计算结果与精细化有限元模型结果比较吻合,最大相对误差不超过5%,可以进一步应用于车-线-桥耦合振动分析。

To solve the question of low computational efficiency of finite element method of double-block ballastless track structure, a simplified finite element （FE） model, i.e., K-G simplified beam model, is proposed to simulate the track structure. The method of adaptive Kriging model and the genetic algorithm are adopted to modify the simplified ballastless track model to obtain the structure parameters. And the results are compared to those of refinement ballastless track structure to verify the feasibility accuracy of the K-G simplified beam method. The K-G simplified model for the ballastless track is employed in a dynamic analysis of vehicle-track-bridge system for Hanjiang Bridge. The results show that the vertical displacement responses of double-block ballastless track simulated with the K-G simplified beam model agree well with those by the refinement FE model with the maximum relative error within 5%. The K-G simplified beam FE model of the ballastless track can be employed in the further dynamic analysis.