Numerical modelling of masonry joints degradation in built tunnels

Old tunnels are generally supported by masonry structure. Nowadays, these constructions present many instability problems (cracks, collapses, convergence, etc.) due to aging phenomena on both blocks and mortars. After the analysis of blocks mechanical behaviour over time [Idris, J., Verdel, T., Al-Heib, M., 2008a. Numerical modelling and mechanical behaviour analysis of ancient tunnel masonry structures. Tunnelling and Underground Space Technology 23, 251–263.], we try in this paper to simulate the evolution of masonry joints mechanical behaviour in built tunnels and to quantify the influence of their mechanical proprieties on the tunnel behaviour by the help of the experimental design method and distinct elements numerical modelling.