Effects of near-fault pulse-type ground motion on train–track–bridge coupled system with nonlinear supports

Researches have revealed that the excitations of near-fault pulse-type (NFPT) earthquakes lead to significant challenge high-speed railway. This paper mainly focuses on dynamic responses train–track–bridge coupled system (TTBCS) under NFPT ground motions. An innovative effective TTBCS model (TTBCM) considering nonlinearities supports is proposed herein, and with model, numerical simulation data analysis are conducted reveal potential effect arisen by motion from both qualitative quantitative perspectives. Conclusions can be summarized below: The comparison between linear nonlinear reveals necessity nonlinearity when conducting Moreover, pulse parameters motions relationship train group amplitude velocity approximately positive correlation relationship, while period exhibits negative as inverse proportional function. Based analysis, a multiple-parameter regression spectral intensity conducted, combination running safety assessment (RSA) criteria including Nadal, wheel unloading, lift, suggestion RSA perspective well.