Authors: Sugeng Wahyudi, Hideki Shimada and Takashi Senda
Abstract: Difficulty of utilization the ground or shallow strata in Japan lead to use of the deep strata. The current technology of pipe jacking method has proven working well at the deep of 20m or more below the ground. At this depth, the burden pressure is high and it might give influence on the pipe driving. In order to reduce the friction between the ground and the pipe, an over-cutting area (so-called tail-void) that filled with lubricants must be formed. However, because the stress release of the ground continues to advance when the over-cutting area is formed, there are some challenges required to cope with the stability of the surrounding ground. This paper discusses the condition of over-cutting area in the deep pipe jacking method and its countermeasure by means of numerical analyses. The countermeasure is done by grouting injection into over-cutting area in regards to dimension as well as properties of improvement region.
Keywords: component; pipe jacking; over-cutting area; backfilling; surrounding soil