Damage detection in a timber bridge model

This paper investigates detecting structural damage by vibration testing in a timber bridge model of 3m×1m×0.2m supported on four stiff columns. Impact hammer tests were carried out to obtain frequency response functions (FRFs) in undamaged and damaged condition inwhich one plank of 90mmwidewas removed. The FRFs were processed by the Damage LocationVector (DLV) algorithm to determine the location and extent of damage. The DLV algorithm requires the dynamic stiffness matrix of the structure which is deducible from a spatial model of the structure. A simple finite element model (FEM) using Bernoulli beam model was used in this paper to obtain the dynamic stiffness matrix and impact vibration testing was used to obtain the FRFs curves. The position and extent of damage was correctly identified by DLV. A more complex FEM model employing plate elements will be investigated.