Seismic vulnerability assessment of masonry buildings in Karachi

Existing masonry structures are severely affected when subjected to strong ground motions, this could be due to the lack of maintenance over the period and the presence of a significant number of seismic vulnerabilities. Restoration and retrofitting are the methods to preserve the aesthetic and overall response of these structures. Therefore, the focus of this research is to employ the non-linear static analysis approach and to investigate the seismic response of existing masonry building structures subjected to strong events. In addition, to develop the fragility functions from empirical and analytical approaches corresponding to different limit states and to assess the seismic performance of historic building stock in Karachi. For this purpose, a prototype masonry structure is modeled on a computational tool 3-Muri and processed through pushover analyses in orthogonal directions considering three different groups of masonry such as Good, Fair, and Poor to incorporate the randomness in material characteristics. Furthermore, results obtained from fragility functions were employed to generate damage matrices corresponding to different intensities of the earthquake. Moreover, for verification of results a comparison of both empirical and analytical approaches illustration is also presented. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.