Vibration analysis and control of a bridge under a heavy truck load

In this paper, vibration response of a bridge under vehicular load is analyzed and subsequently controlled by two actuators using active optimal control strategy. The bridge and the vehicle are modeled as an Euler Bernoulli beam and a four DOF vehicle respectively. To this end, equations of the coupled system of the bridge and the vehicle are derived using Hamilton´s principle, and then transferred to the state space, discretized and finally controlled by the optimal control algorithm designed. Deflection of the mid span is considered as the output of the system and tried to be controlled by two symmetric forces whose optimal positions are determined by minimization of the square root of sum of squares of deflection of different points of the bridge. In addition parametric study has been done to investigate the sensitivity of the system response with respect to different parameters of the system and the controller. And finally the effect of the surface roughness and waviness on the system response and the controller has been studied. It is shown that the optimal positions of the forces are not essentially the mid span of the bridge and by this active control method, the bridge vibration can be well suppressed.