Moving forces identification on a multi-span continuous bridge

A continuous bridge is modelled as a multi-span continuous Timoshenko beam with non-uniform cross-section. The vibration behaviour of this beam subjected to moving loads is analyzed by Hamilton's principle with the intermediate point constraints represented by very stiff linear springs. A method based on the modal superposition and optimization technique is developed to identify the moving forces in the time domain. The damped least-squares method is used in the identification to provide bounds to the results. The errors in the moving force identification are discussed in the paper. Both computation simulations and laboratory tests show that the method is effective for identifying the moving loads using different combinations of measured responses (C) 1999 Academic Press.