Numerical methods for analysis of structure and ground vibration from moving loads

An overview of the main theoretical aspects of finite-element and boundary-element modelling of the response to moving loads is given. The moving loads represent sources of noise and vibration generated by moving vehicles, and the analysis describes the propagation of the disturbances generated in soil. A finite-element time-domain analysis in convected coordinates with a simple upwind scheme is presented, including a special set of boundary conditions permitting the passage of outgoing waves in the convected coordinate system. The modification of frequency-dependent damping to convected coordinates is described, and the convected formulation of boundary elements is presented and used for illustrating the effect of ‘high-speed’ motion. Finally, a procedure for the coupling of a local finite-element model with a boundary-element model of an exterior, or open, domain is described. The paper uses recent results from the Danish research programme ‘Damping Mechanisms in Dynamics of Structures and Materials’ as a basis for a general discussion and review of the recent literature on the subject.