Numerical analysis of historical masonry structures for stone degradation diagnosis : An application to the Roman Amphitheater of Nîmes

This paper features a study which aims at understanding the phenomenology governing the limestone alteration on the Gallo-Roman Amphitheater of Nimes. The simulations are carried out on the LMGC90 platform based on the Non Smooth Contact Dynamics method. The first attempt consists in evaluating the load transfer though the structural elements thanks to a 3D rigid modelling made of 5000 blocks. Special features to generate the complex geometry are also presented. Results obtained from the rigid model are then suitably used to perform a Finite Element Analysis on a deformable block subjected to different factors of degradation. A discussion enlightens the part played by each scenario and finally brings informations for the restoration process.