前言关于地震时饱和砂土地基液化问题,过去已作了许多调查研究,并且还在现场进行了现场判别。但是,要应用地基液化判别结果,对需考虑地基液化的结构物进行合理的抗震设计,尚须对地基液化的特性作定量评价,并查明其对结构物的影响程度。作者以往曾提议采用“液化阻力度(F_L)”作为地基液化的简易判别指标。本文将介绍运用F_L这个指标,对地基液化概率、超孔隙水压值及超孔隙水压对地 Foreword Regarding the problem of liquefaction of saturated sand foundations during earthquakes, many investigations and studies have been made in the past and field judgments have been made on site. However, in order to apply the foundation liquefaction discrimination results to a reasonable seismic design of the structure to be considered for liquefaction of the foundation, it is still necessary to quantitatively evaluate the characteristics of the foundation liquefaction and to determine the extent of its influence on the structure. In the past, the author proposed to use “Liquid Resistance (F_L)” as a simple criterion for liquefaction of foundations. This article will introduce the use of the F_L index, the ground liquefaction probability, excess pore pressure and excess pore water pressure on the ground