Abstract
Immediately after the occurrance of the 1995 Hyogoken-Nanbu (Kobe) earthquake, the Japan Road Association revised the Specifications for Highway Bridges in late 1996. In the course, the author took a role to revise the simplified procedure for assessing liquefaction potential of soils. The main points to be revised were the extent of liquefiable soils, estimation of liquefaction strength of in-situ soils based on penetration blow counts and soil gradation data, and the simplified liquefaction potential assessment procedure. The intent of this paper is to present and interpret the background data, both field and laboratory, that were obtained by a comprehensive study. In particular, a large amount of laboratory liquefaction data are based on those of in-situ frozen samples. At the end of the paper, technical issues to be further studied are also mentioned.
