Effects of bridge motion and crosswind on ride comfort of road vehicles

Ride comfort of road vehicles running on the ground has been extensively investigated as one of the main criteria in the design of road vehicles. The information on the ride comfort of road vehicles running on a long span cable-supported bridge under crosswind is, however, very limited. This paper presents an evaluation of ride comfort of road vehicles running on a long span cable-stayed bridge under crosswind. The ride comfort criteria for road vehicles are briefly reviewed first. The principle of mathematical modeling and the equation of motion of a coupled road vehicle–bridge system under crosswind are then introduced. The framework proposed is finally applied to a group of high-sided road vehicles running on a real cable-stayed bridge under crosswind as a case study. Ride comfort of the high-sided road vehicle under various conditions of road roughness, vehicle speed, and crosswind speed is investigated for the vehicle running on either the ground or the cable-stayed bridge with and without crosswind. The results show that the crosswind influences the ride comfort of the vehicle in the lateral direction while the bridge motion affects the ride comfort of the vehicle in the vertical direction.