Seismic risk assessment of a template school across Nepal is carried out to evaluate the suitability of a single design structure across an area with variable seismic hazard. Many non-governmental organisations (NGOs) use template designs for buildings as a method of reducing design costs; this results in a single seismic design used over a large area. Such an approach is particularly popular in Nepal as the government requires that all school designs obtain approval from the Department of Education. Probabilistic seismic hazard analysis (PSHA) studies have shown a varying seismic hazard across Nepal with the PGA a 475-year return event ranging from 0.05 g to 0.73 g. Pahar trust, a charity that builds schools in Nepal, provided the design of a reinforced concrete (RC) structure with masonry infills. Finite element (FE) models and fragility curves are developed with and without the masonry infill as to explore the effect of masonry infills on the seismic risk. The hazard and the fragility are then integrated to find the seismic risk of the template school across Nepal. The damage distribution is then evaluated for the template school under a 475-year and 2475-year earthquake. The probability of the school exceeding damage limitation (DL) and life safety (LS) has significant geographic variation, with a 475-year earthquake causing the school to exceed DL in most locations and a 2475-year return earthquake causing the school to exceed LS in the majority of locations. The structural contribution of infills brings the risk level below the threshold typically employed as reference in Europe.

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Reinforced concrete (RC) with masonry infill is one of the most common structural typologies in Nepal, especially in the Kathmandu Valley. Masonry infills are typically made of solid clay bricks produced locally in Nepal. This study aims to calibrate the spectral-based analytical method, namely, FAST, for Nepalese RC-infilled buildings. The FAST method has been initially conceived for Southern European RC buildings with hollow clay brick infills. The calibration is achieved by reviewing code prescriptions and construction practices for RC masonry infills in Nepal and updating the FAST method. The variables of FAST method are calibrated using different information sources and a Bayesian updating procedure to consider the global and local material properties for solid clay bricks. The FAST-NEPAL method obtained is then verified, considering a single school design, for which a detailed state-of-the-art vulnerability assessment is available. Being particularly suitable for large-scale assessment, the method is further validated using data from Ward-35 of Kathmandu Metropolitan City (in the vicinity of Tribhuvan International Airport) obtained from photographic documentation included in a geo-referenced database of buildings collected after the 2015 Nepal earthquake and prepared for census purposes. The comparisons show that the FAST-NEPAL method can be conservative relative to the other data sources for vulnerability and is more accurate at capturing low-level damage. This makes the approach suitable for large-scale preliminary assessment of vulnerability for prioritisation purposes.