Abstract: Slurry balanced pipe jacking method is widely used in the urban sewer network construction. Occasionally, if boulders are encountered during the jacking process, the conventional treatment methods will usually have an adverse effect on both schedule and cost. This case history presents a new way to overcome the obstructions in a pipe jacking project in Guangzhou. The new method involves the reversal jacking by using the receiving pit as a temporary launching pit. The reversal jacking is performed with the steel casing protected open excavation. The soil at the front working face is removed by manual hand dig. Jet grout is used in areas adjacent the reversal jacking to seal off the ground water. The case study indicated that this method is successful and cost effective.

Key words: Slurry balanced pipe jacking, Steel casing, Driving and pipe jacking