A unified model for the seismic analysis of brick masonry structures

A significant portion of the building stock in seismic regions all over the world is constituted by brick masonry structures that are well known to be prone to damage under seismic excitations. For evaluating the dynamic performance of masonry buildings, efficient numerical models are required. In this paper, considering the typical hysteretic behavior of brick masonry walls, a unified model for the static and dynamic analysis of masonry structures governed by ten key parameters is proposed. The model is able to simulate different kinds of walls such as unconfined unperforated and perforated walls, as well as confined unperforated and perforated walls subjected to horizontal reverse cyclic loadings and vertical compression. The identification procedure of each key parameter, that includes, among the others, lateral strength, loading and unloading stiffness, accumulated damage factor, shrinkage factor, as well as slipping factor, is presented by analyzing over one hundred results collected from literature. In order to validate the proposed approach, four different types of wall specimens were tested under cyclic loads. Furthermore, a two-storey half-scale structure was tested to verify the effectiveness of the presented model in reproducing the deformation response and global hysteretic behavior of the structure.