Interval dynamic response analysis of vehicle-bridge interaction system with uncertainty

Interval dynamic response analysis of vehicle-bridge interaction system with uncertain parameters is studied in this paper. The bridgeʹs and vehicleʹs parameters are considered as interval variables. A half-car model is used to represent a moving vehicle and the bridge is assumed as a simply supported Euler–Bernoulli beam. By introducing the interval algorithm into the dynamic analysis of vehicle-bridge interaction system, the expressions of the midpoint value, interval width, lower and upper bounds of interval bridge dynamic response are developed. The lower and upper bounds are respectively the minimum and maximum values of bridge dynamic response, which can also be determined by optimization approaches. A heuristic optimization method, a new particle swarm optimization method with low-discrepancy sequence initialized particles and high-order nonlinear time-varying inertia weight and constant acceleration coefficients (LHNPSO), is then developed to find the bounds of bridge displacement. Examples are used to illustrate the effectiveness of the presented methods and Monte-Carlo simulations are implemented to validate the computational results. The effects of individual system parameters on bridge response are also investigated.