Research on dynamic characteristics of multi-type vehicle platoon-bridge coupling system based on the FPEI4–4 scheme

• A comprehensive multi-type vehicle platoon-bridge coupling dynamic model is established. • Pavement, nonlinearity, viscoelasticity, irregularity, and driving conditions are included. • The model considers potential jumping of any vehicle within the platoon. • The FPEI4–4 scheme improves computational efficiency by 20–40 times over classical method. • Focuses more on the driving stability of vehicles within platoons. Vehicle platoon is an effective way to save energy and improve traffic efficiency. While current research mainly focuses on the cooperative control strategy of vehicle platoon, limited attention has been given to their vertical dynamic interactions with bridge structures. Due to the popularity and application of vehicle platoon in the transportation industry, and the significant increase of axle load on traffic structure in the case of platoon, it is imperative to investigate the vertical dynamic characteristics of vehicles under platooning conditions. In this paper, a multi-vehicle-bridge coupling dynamic model was established to analyze the vertical vibration of vehicle platoons crossing the bridges. Force-displacement coupling between vehicle tires and bridge decks, asphalt pavement properties on bridge decks and the viscoelastic and geometrically nonlinear characteristics of bridge materials, as well as the platoon vehicle jump phenomena were considered. Newmark- β and FPEI4–4 (Four-stage, four-order, parameter freezing precise exponential integrator) numerical integration schemes were developed to solve multi-type vehicle platoon-bridge coupling vibration characteristics under different operational conditions. Numerical results indicate that the proposed FPEI4–4 numerical integration scheme improves the computational efficiency of the long-platoon and bridge coupling system by over 20 times while maintaining high accuracy. When two types of vehicles with different axle loads form a platoon, the interleaved platooning mode reduces the peak bridge dynamic response by 20 %. The vehicle speed during bridge-crossing platooning significantly influences vertical vibration characteristics of vehicles. Under interleaved platooning at speeds between 12–18 m/s, the peak RMS values of vehicle ride smoothness indexes of individual light and heavy vehicles decrease by 56 % and 63 %, respectively. And platoon speed should be maintained at a distance from all the resonance speeds induced by individual vehicle models within the platoon. The proposed model is expected to provide theoretical framework for investigating vertical dynamics characteristics of autonomous vehicle platoon crossing a bridge.