damage detection of skeletal strucutres by an enhanced metaheuristic

Damage detection of structures is a rewarding task in many fields of engineering. one important application may be vulnerability analysis of a building system after undergoing unusual/severe loading such as destructive earthquakes. the natural period of structure is very important in evaluating its dynamic behaviour. particularly, the period shifts due to repeating aftershocks (schaff et al., 1998), can be utilized within a quantitative index to measure vulnerability and pursuerehabilitation of a damaged building. a common approach to localize and determine severity of the damage in a structure is formulating it as an inverse problem (friswell, 2007; kaveh and zolghadr, 2015). it means generating alternate structural models with different damage states and seeking for the one that coincides with the actually-damaged structuralcondition. the present work applies such an approach via an optimization problem to find the best match of structural properties with the given damage state. the first treated cost function is thus defined as an error-sum over the difference between the consequent modal properties (equation 1).