Despite intense worldwide research in the area of masonry infilled frame structures during the past half a century, displacement-based non-linear analyses of masonry infilled frames with explicit consider-ation of infill panels as structural elements is far from common practice in earthquake-resistant design of such structures. The displacements are of particular interest from the viewpoint of performance-based design (PBD), the emerging paradigm for the next generation of standard codes of practice for earthquake-resistant design. The present paper is based on an analytical study of the seismic perfor-mance and vulnerability of typical planar masonry infilled reinforced concrete (R/C) frames considering the effect of distribution of masonry infill panels over the elevation of the R/C frame using rational displacement-based analysis methods such as non-linear dynamic time-history analysis based on real-istic and efficient hysteretic models of the structural elements. The results of the displacement-based analyses are used to develop seismic vulnerability curves in probabilistic terms for the populations of typical medium-rise masonry infilled R/C framed buildings. The proposed seismic vulnerability curves are termed as fragility curves in the present study that provide useful tools for predicting life and eco-nomic losses in the event of a future earthquake.
Fragility analysis, performance-based seismic design, seismic demand, seismic vulnerability
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