An Efficient Model for Train‐Track‐Bridge‐Coupled System under Seismic Excitation

Abstract

When an earthquake occurs, due to the high operation speed of the train group, there is still a long distance from braking to stopping, so it needs a large number of bridge spans to calculate the integrated dynamic response, which leads to a large amount of calculation of the train-track-bridge (TTB) system under a seismic event. In order to reduce the amount of calculation, this paper proposed an efficient model called closed-loop model for simply supported railway bridge. The proposed model is realized by coupling the head and end of the rail-slab-bridge system through the utilization of pseudo-element. Simulation comparison of TTB response with and without seismic excitation between conventional TTB model and efficient model indicates that, under the premise of ensuring calculation accuracy, the efficient model shows the advantage of fewer degrees of freedom (DOF) of model and higher computational efficiency. For instance, under El Centro earthquake excitation, the time cost of proposed model is only 6% of conventional model. Meanwhile, six seismic events with different acceleration amplitudes are imposed on the efficient model, and the results of car-body acceleration, wheel-rail force, and wheel load reduction ratio are gathered and discussed; it can be concluded that, except Trinidad earthquake, for other earthquake samples investigated in this paper, with acceleration amplitude larger than 0.8 g, the train operation is at the risk of derailment.

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

“…The closed-loop model utilized herein is based on the past research conducted by Jiang [17] and Zhou [42], which is aimed to enhance calculation efficiency and reduce total DOF of model by…”

“…From another perspective, researches aiming to ensure safety of trains running under earthquake are pushing forward simultaneously [17][18][19][20][21][22][23]. Yang and Wu [24] preliminarily proposed a criteria based on YQ ratio for derailment under seismic excitation, and in this research, the lateral peak ground acceleration of ground motions (PGA) and train speeds were considered.…”

Random analysis of train-bridge coupled system under non-uniform ground motion

“…Subsequently, Illustrative Examples shows the influences of Figure 1. A high-speed train running on a simply supported bridge and a long high-speed railway bridge (Liu et al, 2021;Jiang et al, 2021).…”

“…Afterward, Li and Lei studied the extreme response of the hybrid bridge structures for rigid-frame and continuous girders with traveling seismic wave effect (Li and Lei, 2012). Nevertheless, there are still many problems with HSR bridges under the traveling wave effect due to complex train running conditions, the limitation of model accuracy and calculation efficiency.

Figure 1.A high-speed train running on a simply supported bridge and a long high-speed railway bridge (Liu et al, 2021; Jiang et al, 2021).

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“…A high-speed train running on a simply supported bridge and a long high-speed railway bridge (Liu et al, 2021; Jiang et al, 2021). …”