Parametric analysis of out-of-plane façade overturning

Abstract

Masonry structures show great vulnerability during earthquakes. In this paper, emphasis is placed on the out-of-plane failure mechanisms, which occur due to inadequate wall-to-wall and wall-to-floor connections. The following out-of-plane façade overturning mechanisms are analysed: i) vertical overturning of the façade and ii) overturning of the façade with one side wing. A parametric analysis was carried out and diagrams of the activation factors of the mechanism and spectral acceleration were created. The analysis is based on defining the geometry of the blocks included in the mechanism, the boundary conditions and the loads acting on the wall. The activation factor of the mechanism can be obtained by applying the principle of virtual work or by using the equilibrium equation of the overturning and the stabilizing moment. Based on the activation factor of the mechanism, the value of the spectral acceleration of the activation of the mechanism is obtained, which should meet the criteria of limit states. The effect of stabilizing horizontal forces in the form of ties installed in the floor plane was also considered.