Modelling of the dynamic response of a reduced scale dry joints groin vault

Abstract

The relevance of the safeguard of masonry cross vaults is evident in churches, palaces, and cloisters of most European countries. Nevertheless, their seismic behaviour is still an aspect to be deepened. In this regard, the purpose of this paper is to study the dynamic three-dimensional behaviour of a reduced scaled dry joint groin vault. The work involved simplified micro-modelling, based on the finite and discrete element methods, for reproducing the experimental campaigns of the vault subjected to seismic loads. The research can be divided into four phases: the first one corresponds to an overview of numerical modelling approaches, specifically focused on cross vaults; the second one consists of the calibration of the numerical models, based on the experimental outputs; the third phase highlights advantages and disadvantages of the two modelling strategies adopted through qualitative and quantitative comparison, such as ultimate strength capacity, failure mechanisms and time histories of displacements. Lastly, a sensitivity analysis on the influence of several recorded inputs on the same mock-up is shown. In general, both numerical models simulate correctly the experimental responses, representing an improvement with respect to previous models available in the literature, in fact, the ability of the discrete element method to reproduce the collapse mechanism of the vault was rarely investigated. Moreover, in this contribution the importance of the modal properties for the numerical calibrations, the quantitative differences between the discrete and finite element methods and finally the role of the seismic parameters at the level of the collapse are investigated and commented.