Three-Dimensional numerical modelling of historical masonry stuctures affected by tunnelling-induced settlements

This paper focuses on the interaction between tunnelling and historical masonry structures. These latter often characterise the centre of many cities and should be preserved from possible tunnelling-induced damage. In recent years the Authors of this contribution have adopted an advanced numerical approach to investigate this issue in the two-dimensional domain, schematising the block masonry structure as a homogenised anisotropic medium [1, 2]. This study extends the approach to three-dimensional conditions. The behaviour of masonry is described by a modified version of the Jointed Rock model, named hereafter as Jointed Masonry model, an anisotropic elastic perfectly plastic constitutive model implemented in the code Plaxis 3D. This model takes into account the directional properties of the medium, identifying the orientation of three planes along which the Mohr-Coulomb yield criterion applies. The paper first briefly describes how the original Jointed Rock model was modified to more realistically account for some specific features of the nonlinear mechanics of masonry. This is followed by the 3D analysis of a tunnelling-structure interaction problem, aimed at highlighting the key features of the proposed masonry model.