Improving the seismic resistance of masonry buildings : concepts for cultural heritage and recent developments in structural analysis

Conservation and restoration of historical structures are still a challenge to modern practitioners even if considerable research advances have occurred in the last decades, namely with respect to non-destructive testing, mechanical characterization, tools for advanced numerical analysis, knowledge on traditional materials and techniques, and innovative materials and techniques. In the paper, the ICOMOS Recommendations for the Analysis, Conservation and Structural Restoration of Architectural Heritage are briefly reviewed, together with recent developments in structural analysis. The proposed methodology is applied to Monastery of Jerónimos, in Lisbon, Portugal, including the following steps: seismic action characterization, from the identification of earthquake source areas to the artificial generation of acceleration time histories, using specific theoretical models and including superficial site-effects; simple numerical modeling for a preliminary knowledge of the structural behavior; experimental mechanical characterization of materials and structural elements; installation of static and dynamic monitoring systems aiming at a better understanding of the static and dynamic behavior; development of advanced numerical models including calibration against relevant experimental data; non-linear dynamic analysis of the structure for different earthquake levels