68th Canadian Geotechnical Conference and 7th Canadian Permafrost Conference

EFFECTS OF TUNNELLING ON THE BEARING CAPACITY OF SHALLOW FOUNDATIONS

Anna-Maria Zakhem, Dalhousie University (Canada)
Hany El Naggar, Associate Professor (Canada)

Urban tunnelling can induce distortion to the existing three-dimensional stress regime due to the development of ground arching and the associated stress redistribution. In some cases this may decrease the bearing capacity of nearby foundations which could cause damage to the overlying structures especially in soft soils and/or densely populated areas. Thus, the effect of tunneling on the performance and capacity of nearby foundations may be significant and should be considered in their design. This paper uses the finite element method with an elastic-plastic model and the Plaxis 3D software to study this interaction problem considering a number of parameters such as the tunnelling processes, construction sequence, proximity, and the burial depth. Accordingly, recommendations for the design of shallow foundations in close vicinity to shallow tunnels were proposed.