Analysis of fault effects on the stability of large underground caverns

The stability of large-scale underground caverns, such as underground openings for hydropower houses, is often affected by faults or joints located nearby. Hence, a better understanding of the mechanisms of influence. especially regarding the risk assessment of faults is required. At the department of geotechnical engineering, the influence of faults on the stability of underground openings has been investigated using numerical methods. Faults are modeled here explicitly as an interface of two planes contacting each other. The interface is represented by the stiffness in the normal and in the shear direction of the two planes. In this paper. especially the displacement behavior for different locations of a fault around the underground opening are discussed. The deformation of the fault after the excavation is also briefly presented.