An Efficient Solution for Train–Track–Bridge Interaction Analysis Considering Wheel–Rail Dynamic Contact

To address the issue of low computational efficiency in analyzing the dynamic response of train–track–bridge coupled system (TTBCS) considering wheel–rail dynamic contact, this paper proposes an efficient calculation method by constructing wheel–rail contact coupling matrices. In this method, the train is modeled using multi-body dynamics, the track–bridge is simulated via the finite element method, and wheel–rail contact is represented by a trace line-based elastic contact algorithm. By establishing time-varying coupled vibration equations for the TTBCS, the proposed method avoids computational instability issues caused by the loosely coupled method (LCM). Compared with existing methods, the innovations of this approach mainly lie in two aspects. First, a generalized treatment of lateral equivalent wheel–rail contact stiffness applicable to arbitrary wheel tread profiles is developed. Second, a novel strategy is proposed to address the coupling matrix derivation challenges between the wheelset yawing degree of freedom (DOF) and other DOFs. Numerical validation is conducted using a CRH2 high-speed train traversing a 7-span simply-supported beam bridge. The method’s correctness is first verified through comparisons with field measurements. Subsequently, computational accuracy and efficiency comparisons with the LCM are performed under two track conditions: irregular continuous welded rails and regular rails with welded zones. Results demonstrate that the proposed method achieves comparable accuracy with the LCM across various speeds while improving computational efficiency by 12–23 times.