Abstract
Unreinforced masonry (URM) buildings exhibited extreme vulnerability during past earthquakes though these are shelters of majority population in many earthquake prone developing countries. Most of the current retrofitting techniques used for such structures are either expensive or requires highly skilled labor or sophisticated equipment for implementation. On the other hand, the retrofitting technique proposed in this paper is economical and easy-to-apply. This paper aims at examining the performance of the retrofitting technique using polypropylene (PP) band. The displacement controlled lateral deformation has been investigated experimentally. The monotonic load-displacement behaviors of URM wall and the wall retrofitted with PP band are compared. It was found that URM wall retrofitted by PP band improves the ductility and energy absorption capacity by three times, and two times, respectively. Performance of a full-scale masonry building retrofitted with PP band in Nepal during last Gorkha earthquake of April 25, 2015, has also been presented in this paper. It was observed that the PP band retrofitted masonry building survived while the nearby many buildings experienced severe damage and some of them collapsed. This study demonstrates the efficacy and practicability of use of PP band for improving seismic resistance of URM structure.