The Influence of the Passive Earth Pressure and other Factors on the Stability of the Underground Masonry Vaults of the Paris Metro

. This paper presents an analysis of the behavior of masonry tunnel vaults of the Paris metro when their state of equilibrium is altered. These tunnels were built with a masonry vault combined with sidewalls and a slab made of unreinforced concrete. The main case studied here is that of the spreading of the vault’s supports as a result of nearby construction works. Numerical computations are carried out using a specifically developed model for the masonry that combines a homogenization technique with damage models. An interface between the tunnel and the ground allows the study of the soil-structure interaction. The proposed model identifies the possible hinging failure mechanisms and their configuration based on the horizontal displacements and the geometry of the structure. Several other simpler constitutive laws for the masonry are also used and then compared with the proposed model. An analysis on the loss of the passive earth pressure and the deformation of the structure are also provided. Based on the numerical simulations made and real measurements, it was observed that the studied underground masonry vaults may withstand several