2.6 Summary of Review

From the above review of previous studies on deep excavation problems, it can be found that the design approach for excavation progressed from the traditional methods based on earth pressure theory to advanced numerical analyses. The past concern on the stability of excavation have now shifted to emphasis on the control of wall deflection and ground movements under working condition in densely built-up area. The numerical methods with appropriate consideration of relevant factors, have the potential to give relatively accurate solution for both the stability and the ground movements for an excavation. However, there is still a long way to establish a perfect model to predict the collapse of support system and evaluate the ground movement at some distance behind the retaining wall at working condition. More detailed studies are clearly needed to learn the mechanism of the behaviour of the wall and the soil so as to improve existing numerical methods. The centrifuge study proposed in this thesis is aimed to provide information and some answers to solve the problem mentioned above.