A digital tool based on code indicators to assess the seismic behaviour of existing masonry structures: Application to Croatian residential buildings

This paper proposes a methodology to define code-based indicators of the seismic behaviour of existing masonry structures. Given the geometrical information about the structure under investigation, the proposed method performs real-time structural checks according to the EN 1998–1 – “General rules, seismic actions and rules for buildings”. Then, modal analysis is performed to assess the structure's dynamic behaviour under investigation and to assist the user in defining retrofit measures. In this study, 103 masonry buildings located in Zagreb are analysed, accounting for the cross-sectional area of load-bearing walls, geometric requirements for shear walls, regularity of plan configuration and its symmetry, torsional effects induced by the distance of the centres of mass and stiffnesses, and modal analysis. The workflow is implemented into the environment offered by Rhino3D and Grasshopper, which allows for the parametric handle of a large set of information through object-oriented scripts, and it can be valuable for both pre-earthquake and post-earthquake assessments of masonry buildings.