Assessment of the Seismic Vulnerability of Existing RC Buildings and Effect of the Irregular Position of the Masonry Panels on the Fragile Collapse Mechanisms

Abstract:

The present work deals with the evaluation of the level of seismic vulnerability of reinforced concrete existing buildings situated in high seismic zone and designed for only gravitational loads. For assessing seismic performance, a Displacement Based Approach (DBA) is adopted and in particular the N2-metohd is used, according to Italian seismic code NTC 2008. The effect of the masonry infills on the seismic response of the structure is considered and a nonlinear model is adopted for all the panels considered in effective interaction with the frame structure. It is shown that the effect of the masonry infills, if improperly located within the building, can give rise to a worsening of the seismic performance of the structure. In fact particular locations of the masonry infills within the building can give rise to a fragile structural behavior due to a collapse mechanism of soft storey. A comparative analysis of a building is performed by considering the effects of the masonry infills and by considering the bare structural frame and it is shown that fragile collapse mechanisms can occur depending on the location of the effective masonry infills within the building. Consequently it is discussed how in a vulnerability analysis the procedure of neglecting the masonry infills not always is a procedure which operates for the benefit of security.

• Periodical: Advanced Materials Research (Volumes 602-604)
• Pages: 1555-1565
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.602-604.1555
• Online since: December 2012
• Authors: Donato Cancellara, Fabio de Angelis, Vittorio Pasquino
• Keywords: Assessment and Seismic Retrofitting, Displacement Based Approach, RC Building

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