SEISMIC FRAGILITY ANALYSIS OF RC RESIDENTIAL BUILDINGS OF PANCHKHAL MUNICIPALITY

Abstract

Nepal lies on an active convergent plate boundary, making it prone to earthquakes. The real cause of economic and life losses due to earthquakes are structures built without proper seismic design. The country's structures must be analytically studied to understand their seismic performance, estimate potential losses, and plan for risk minimization through engineering methods like retrofitting. Panchkhal Municipality’s RC residential building stock has been chosen for a vulnerability study using the fragility analysis method. All buildings with completion certificates were studied. The 28 most populous models were chosen as representatives. Capacity and demand parameters were calculated by pushover and FNA time history analysis, while uncertainty parameters were taken from the HAZUS manual. An overall study showed that 2 story (Pre-Code) and 3-story buildings (all design levels) would show an unacceptable level of performance during a design-basis earthquake. Retrofitting can be targeted for them, mainly for the ones with the least number of columns per unit plinth area (even if they have regular geometries), irregular shapes with a lesser number of columns, and ones with single bays. Discontinuation of older design codes and strict follow-up of the latest NBC105:2020 are suggested for the municipality.