Improvements in the accuracy of system identification and nondestructive damage evaluation in civil engineering structures

Many system identification (SID) techniques for estimating structural parameters and nondestructive damage evaluation (NDE) algorithms for assessing the structural integrity of civil engineering structures have been proposed and developed on various theoretical and experimental grounds. The identified structural parameters of the structures obtained using SID techniques can then be applied to the problems of NDE. Inaccurate results from a SID technique may yield incorrect locations and severity estimation of damage obtained from an NDE algorithm in civil engineering structures such as offshore structures and bridges. Therefore, more accurate SID and NDE methods for structural systems are paramount and one of the more pressing problems in the civil engineering field. In order to improve the accuracy of a SID technique and an NDE algorithm in civil engineering structures, the use of additional spectral information and an improved damage index are explored in this study. First, a baseline SID technique and NDE algorithm are selected. Second, an extended SID technique including additional spectral information and retaining the basic structure of the baseline SID is derived. Third, an extended NDE algorithm is developed to overcome some limitations of the baseline NDE algorithm. To demonstrate the improvements of the accuracy in SID and NDE using the extended methods, numerical and experimental studies are performed.