Push ‘o ver. Numerical simulation of the Castel di Lama pushover test through a force-based equivalent frame model

The experimental pushover test performed on the Castel di Lama building is studied by means of a finite element procedure based on the equivalent frame model with the aim to test the ability of this widespread model to reproduce the experimental results and the collapse mechanisms. Pier and spandrel macroelements are modelled as Timoshenko beams with plastic hinges to take into account shear and bending failures. Assuming the nodes as infinitely rigid and resistant, it is possible to model them by introducing properly sized offsets at the ends of pier and spandrel macroelements. A force-based formulation is adopted for the macroelement, taking advantage of its higher performances in terms of accuracy and efficiency with respect to the classical displacement-based method, and the capability of naturally avoiding shear-locking problems. The response of the building walls, either unreinforced or reinforced, is analysed in terms of resisting forces, story displacements and damage patterns, and compared with the experimental results.