Seismic design of a stone vault

This paper describes the seismic design of a contemporary stone vault supported by slender buttress walls. Initially, the potential for out-of-plane overturning collapse of the buttress walls was assessed using analytical dynamics and a suite of scaled earthquake time histories. Results informed design decisions related to wall slenderness. Subsequently, discrete element modelling and time history analysis were used to evaluate the seismic response of the entire structure. The structure is found to remain stable for a suite of design earthquake time histories, and the residual displacements after the earthquake are quantified. The effect of initial vault spreading, due to large lateral thrusts, on the dynamic response is also considered. The magnitude of residual displacements due to the earthquake is shown to increase with the presence of relatively small initial spreading prior to a potential earthquake event. The paper closes with a discussion of potential measures considered to resist seismic loading. The extent to which these measures were incorporated was largely based on construction methods and constraints. Construction of the vault was completed in 2015.