Deep excavations stabilization with ground improvement or cross walls: A comparison of both stabilization methods

摘要

Deep excavations in soft ground often need stabilization. One of the stabilization method is to use Cross Walls (CW). The CWs act as mega props to reduce wall deflection effectively. The use of CW in deep excavation in Singapore has become more and more popular nowadays due to the highly developed urban landscape and the widespread presence of soft clay. Another popular stabilization method used in Singapore is the Ground Improvement (GI) inside the excavation. This method is based on the gaining of stiffness and resistance by mixing soil, water and cement. The main difference between GI and CW is that the first is based on the improvement of the soil by mixing it with other materials, while the second is based on the improvement of the soil by replacing it with other materials. The objective of this paper is to compare CW and GI as stabilization methods. To do so, firstly the CW and GI stabilization methods will be described, subsequently the pros and cons of the use of each method are presented. This paper does not define a “right and wrong” method; however, it can be used to understand some of the factors that can define the use of one stabilization method or the other.