Dynamic Behavior of Orthotropic Rectangular Plates under Moving Loads

The dynamic behavior of an orthotropic plate simply supported on a pair of parallel edges and under a system of moving loads is analyzed based on Lagrange equation and modal superposition. Thin plate theory is assumed for the plate model and no restriction is placed on the type of loading. Parameters of the plate affecting its dynamic behavior are discussed, and a new classification of the plates for computing the mode shapes and natural frequencies is proposed. The impact factors and the dynamic responses of a typical bridge deck are studied using the proposed method. Preliminary results indicate that the effect of eccentric loads on the impact factor depends on the proportion ratio between the flexural and torsional rigidities of the bridge deck, and the multilane loading case is less critical than a single-lane loading case.