Comparative Cost Analysis of Possible Seismic Retrofitting Schemes for Multi-Story Unreinforced Masonry Building

Abstract

The core objective of this study is to identify the cost effective seismic retrofitting option for multi-story unreinforced masonry (URM) buildings. A seismically deficient 3 story URM structure assumed to be located in the moderate seismic zone of Bangladesh is taken as a reference for this work. Depending on the expected seismic performance level, 5 possible retrofitting schemes are designed for the building and then compared in terms of cost of construction. It is evident from the study that, the ‘Splint and Bandage’ and the ‘Internal Concrete Box’ are the cheapest solutions considering ‘Life Safety’ and ‘Immediate Occupancy’ performance level respectively. Expensive retrofitting options like ‘Seismic Isolation’ and ‘Internal Concrete Box’ have added advantage to withstand multiple earthquake events over the cheaper methods such as ‘Splint and Bandage’ and ‘jacketing’.