In current practice, estimating the effects of tunnel construction in soft ground beneath an existing building is usually a two-stage procedure, where interaction between the ground and the building is ignored. This paper describes a study of tunnelling-induced settlement damuge to masonry buildings, using a numerical model, in which interaction is included. 2-dimensional finite elements(FEs) are used with non-linear material models for the soil and for a masonry façade. The excavation of a tunnel is simulated, and the resulting damage in the façade, principally cracking, can be observed. This study concentrates on the effect of façade weight and stiffness and the horizontal location of the façade with respect to the tunnel axis. The study finds that increasing facade weight tends to increase damage, owing to the larger horizontal strains. Increasing facade stiffness, however, appears to reduce damage, since the differential settlements under the facade are inhibited.
G. Liu, Professor G.T. Houlsby and C.E. Augarde