System identification of bridges using recorded seismic data and its application in structural health monitoring

A general framework for structural health monitoring (SHM) of bridges employing system identification (SI) and performance evaluation methodology based on sparsely recorded seismic data is presented. Components of SHM are described and a theoretical formulation for SI of a non-classically damped, base-isolated bridge system is derived and implemented for four bridges. The performance of the base-isolated super-structure is examined by comparing the behavior of isolation bearings with the experimental results carried Out in the laboratory. The influence Of soil-structure interaction (SSI) is examined by comparing the identified Values with the theoretical physical properties or the pile-supported sub-structure. It is concluded that the proposed SI methodology is effective and the proposed performance evaluation methodology can be implemented in SHM of bridges. Copyright (C) 2008 John Wiley & Sons, Ltd.