Earthquake-induced damage localization through non-linear dynamic analysis

The development of vibration-based long-term SHM methods for damage detection and preventive conservation of historic masonry buildings is receiving a growing trend of scientific interest. At the state of the art, well-acknowledged techniques for damage detection have been developed and validated, especially when dealing with earthquake-induced damages. The next scientific challenge to deal with in SHM is therefore damage localization, thus, not just detecting the occurrence of a damage, but also inferring, with a certain level of confidence, its location. This paper presents a methodology aimed at addressing the damage localization task in heritage masonry structures, based on Incremental Dynamic Analysis (IDA) carried out from a numerical model together with data recorded during the earthquake. IDA curves are built with reference to different portions of the structure, relating some local damage parameters (DMs) to some seismic or response intensity measures (IMs) and earthquake's intensity is used for locally identifying the damage in such portions. The choice of IM represents an important aspect of the IDA curves effectiveness and an appropriate study is carried out. The proposed methodology is validated through application to the numerical model of a reduced-scale masonry structure, called Brick House, which represents a well-known international benchmark case study tested on the LNEC-3D shaking table. The obtained results demonstrate that the proposed methodology is capable of achieving earthquake-induced damage detection and localization with a good level of approximation.