Three dimensional finite element analysis of a novel bracing system in small deep excavations

Özlü, Pelin
One of the most common retaining systems for deep excavations is by supporting a wall with multiple levels of anchors. In densely built urban areas, preventing soil movement with such a system can be very costly. Additionally, anchored walls are assumed and forced to act independently during design calculations, thus fail to take the advantage of the rigidity of the whole system at the corners of the excavation area. An alternative support system that uses the entire system is bracing of the walls with struts. But such a system greatly hinders construction space. In this research, a new type of supporting system has been investigated by performing a parametric study in finite element analyses program. New system is a single ring at each support level, supporting the system at several locations. A comparative study has been undertaken between the conventional systems and the new system in both 2D and 3D. PLAXIS finite element analysis software was used for the analyses. The primary aim was to investigate the structural and geotechnical performance of the arch supported system. The study revealed that the new system provides improvement for specific cases and can be considered as an alternatve support system for such cases.