Research on Key Parameter Optimization Method of High-Speed Railway Vehicle-Bridge System Based on Proxy Model

This paper proposes a key parameter optimization method for a high-speed railway vehicle-bridge system using numerical calculations, proxy models, and optimization design. A three-dimensional vehicle-bridge coupled dynamic model is constructed to calculate the vertical acceleration of the vehicle body under different sampling combinations. Based on this, a Kriging proxy model of vehicle body vertical acceleration is constructed to accurately describe the relationship between vehicle axle weight, bridge creep deflection, and vehicle body vertical acceleration. A matching optimization model for vehicle axle weight and bridge creep deflection is proposed, with the objective of minimizing vehicle body vertical acceleration. The cuckoo search algorithm is utilized to obtain the optimal design parameters. The results show that the sensitivity of vehicle body vertical acceleration to creep deflection is much higher than that to vehicle axle weight. The optimal vehicle axle weight for a high-speed railway is 15 t, and the creep deflection limit for the bridge is 3 mm, resulting in a minimum vehicle body vertical acceleration of 0.4909 m/s2. This method provides an important basis for controlling bridge creep deflection and vehicle design from a system-level perspective.