Experimental damage localization in a full-scale 7 story benchmark building under seismic excitation

In this paper two methods of damage localization previously proposed by the authors are combined to smooth the possible drawbacks and boost the advantages each of them. The Modal Interpolation Method (IM), recently proposed, is based on a damage feature defined in terms of the loss of smoothness (that is local increases of curvature) of the modal shapes induced by a local reduction of stiffness. Herein the combination of the IM with the Curvature Evolution Methods (CEM) is proposed. The CEM is based on the use of a Band-Variable Filter able to extract from recorded responses the nonlinear response of one mode of vibration enabling the detection of possible changes of a properly defined damage feature, during a single earthquake. In the CEM the modal curvature is assumed as damage feature. The combination of the two methods CEM and IM is carried out using the Band-Variable Filter to extract the nonlinear response of the structure and assuming as a damage feature the variation of the interpolation error computed at different times during the strong motion.