Ground motion characteristics of the 2015 Gorkha earthquake sequence

On 25 April - 12 May 2015, a series of large earthquakes struck the north-central part of Nepal, causing not only a substantial number of casualties, but also heavy damage to the building structures and infrastructure facilities. Up to now, most of seismic reconnaissance studies about this event have attributed the structural damage and life losses to the relatively loose implementation of the building design codes in Nepal, as most of those damaged structures were largely owner-built. Based on the quite limited ground motion data, this paper investigated the primary characteristics of the Nepal earthquake sequence. It is highlighted that the pulse-like features are significant at both the soft and rock sites, which is also responsible for the unique characteristics of the main-shock ground motions other than site effects.