ABSTRACT

This chapter discusses the Cheng worked on several major excavation and lateral support system works in Hong Kong with different types of ground conditions, and some practical considerations and precautions. The most critical problem with the soldier pile wall system is the water leakage and stability of the cutting face before lagging is installed. Some approximate formulae have been proposed in the past, but most of these are readily applicable to real problems, and most of the engineers still adopt the 2D lateral earth pressure as discussed for the actual design work. Moment reduction in the free-earth method is a superficial phenomenon, and is simply due to the use of the ultimate active and passive pressure coefficients which are realistic. Besides the free-earth method, there is also a fixed earth method, which assumes that the sheet pile is long enough so that a hinge is formed at a certain distance below the sheet pile.