Pounding in Nepalese school buildings

The seismic performance of a two storey RC school in Nepal is assessed using non-linear time history analysis (NLTHA). The school was constructed by Pahar Trust and utilizes a seismic gap to avoid issues caused by the torsional effect of the off centre stair case. A fibre model the of RC structure is implemented in finite element (FE) open-source software OpenSees, where NLTHA is employed to assess the seismic performances under different input motions. In particular, three sets of accelerograms are selected: (i) recorded waveforms of the 2015 Gorkha earthquake, (ii) a code-compatible selection compliant with pre-Gorkha earthquake probabilistic seismic hazard analysis (PSHA), (iii) a code-compliant selection compatible with post-Gorkha PSHA. The inter-storey drift demand and the effectiveness of the seismic gap is then assessed. The inter-storey drift values are used to verify the performances of the school against Eurocode 8 capacity limit. The seismic gap provides adequate clearance to avoid pounding when the structure is exposed to the Gorkha ground motions and life safety limit state (10% probability is 50 years) motions for pre-Gorkha PSHA. The structure exhibits pounding with a small number of the post-Gorkha ground motions. A fragility curve for pounding is finally obtained for the school using Cloud Analysis linear regression approach.