Innovative Central Opening Strut System for Foundation Excavation

A central opening strut system is used to support a diaphragm wall for foundation excavation. This system contains at least one regular polygon module and a number of straight strut members. These strut members connect the diaphragm wall and the regular polygon module together, so that the earth pressure acting on the diaphragm wall in one direction can be transmitted to the diaphragm wall in the other directions by the arch action of this polygon module. In this research, the basic structural behavior of the central opening strut system is examined. A full-scale structural testing of the joint subassemblage is also performed to examine the ultimate strength of the joint. A construction site with five excavation stages and four layers of strut systems is chosen as the case study. The ABAQUS finite-element program is employed in the study of the behavior of this system during various construction stages. From these studies, it is found that the proposed central opening strut system is able to provide a large working space and greatly increases the efficiency of the construction work. Through proper design of the member and the joints, this system provides a better safety factor as compared with the traditional strut system.