AN IMPROVED PRECISE COMPUTATION METHOD FOR DYNAMIC RESPONSE OF BRIDGES UNDER MOVING LOADS

In this paper, an improved precise-time step integration method is used to solve the dynamic equation of bridges under moving loads. The characteristic of moving load is simulated as a set of equivalent joint loads in terms of Hermite function. The Duhamel integration format of moving load during a time interval is derived, including all the possible relative positions of moving load at the start time and at the end time: on the same element, neighboring elements, or non-neighboring elements. The numerical example shows that the solution by the proposed method is consistent with the analytical solution and the accuracy is independent of time interval. Accurate solution of bridges under multiple moving loads from the proposed method can be obtained by only one integration step and the computing time is relatively short.