The state of the art in mitigation of liquefaction for lifeline facilities in Japan

ABSTRACT

In Japan, studies on the mitigation of liquefaction have been carried out since the 1964 Niigata earthquake. As a countermeasures against liquefaction, a compaction method such as the Sand Compaction Pile Method has generally been employed for the foundations of fuel tanks. Recently, various points of in-situ soil improvement methods have been put into practical use. This paper reviews the following three items 1) The present state of the in-situ soil improvement methods designed to reduce liquefaction in Japan, 2) The latest research on the utility lines and manholes used in the lifeline facilities, 3) Design, construction methods, and examples of the application of the Sand Compaction Pile Method, the Gravel Drain Method, and the Deep Mixing Method.(AU)