Comparison of Different Model Updating Algorithms to Detect Damage in A Structural Slab Using Mode Shape Data

Abstract

Vibration-based damage detection (VBDD) is one of the techniques used in Structural Health Monitoring (SHM) for detecting structural damage. VBDD provides more efficient, reliable and economical methods to improve the safety and reduce the cost of maintenance in structural engineering. This paper investigates the performance of model updating (MU) method using different types of algorithms in damage detection. A finite element analysis is performed to obtain dynamic properties of undamaged and damaged slab structure for model updating process using different types of algorithms. Three optimisation functions of different algorithms employed in this study are constrained optimisation, least-square optimisation and multiobjective optimisation. Different damage cases are introduced at different locations with different damaged intensities by reducing the structure's elastic modulus in corresponding segment. The performance of MU is evaluated by Stiffness Reduction Factor (SRF). The comparison of SRF for actual value and predicting value is made to check the applicability of three types of algorithms in damage detection. Mean Square Error (MSE) is applied to evaluate stopping and tolerance criteria effect on result improvement. The results show all three types of algorithms are capable to provide reliable results in damage prediction and an improvement of result has been made when increasing the stopping and tolerance criteria.