Using the shear strength reduction method to assess the stability of retaining structures adjacent to excavations for the University of Cape Town’s New Engineering Building

摘要

The construction of the New Engineering Building (NEB) on the University of Cape Town’s(UCT) Upper Campus raised concerns about the stability of the adjacent Ring Road. This busy internal roadran along the western boundary of the site, and was supported by a tapered retaining wall which was 6.3mat its highest point. Hence, a slope stability analysis was conducted on the critical section of the wall usingconventional limit equilibrium (LE) techniques as well as the shear strength reduction (SSR) finite element (FE)method. The results of these analyses were compared and deemed the retaining wall to be safe against a globalfailure. The benefit of combining the LE and SSR FE methods was highlighted by the correlation between the LEfailure surfaces and the development of shear strain behind the wall. Furthermore, the SSR FE analysis yieldeda distinct band of shear strain behind the wall which further exemplified the usefulness of the SSR FE techniquein modelling the deformation behaviour of the system.