Advancing BIM-to-FEM Automation: an Enhanced Framework for the Structural Analysis of Unreinforced Masonry Buildings

The structural analysis of historical unreinforced masonry buildings poses significant challenges due to their complex geometries, material uncertainties, and nonlinear behaviour. In a previous work, the authors developed an automation framework that facilitates the transition from BIM architectural models to finite element analysis in OpenSees [1]. However, aspects such as slab representation, interface modelling, and meshing strategies needed further refinement to enhance automation, computational efficiency, and accuracy. This paper introduces new strategies to improve and expand the framework. A novel approach to processing multi-layered slabs distinguishes between structural and non-structural components, converting the latter into equivalent loads to enhance load distribution accuracy. Furthermore, an automated algorithm for modelling timber-masonry interactions generates zero-length elements to simulate nonlinear behaviour effectively. The framework also enhances mesh generation by proposing an adaptive mesh based on the geometry. These advancements significantly boost the scalability, reliability, and applicability of the framework, enabling the automated structural assessment of both historical and existing unreinforced masonry buildings.