砂質土のコーン貫入抵抗と三軸液状化強度

Abstract

A new practical method for evaluation of soil liquefaction by means of the Cone Pene-tration Test (CPT), proposed by the authors (1987), was reviewed. The critical normalizedcone resistance, (qc1)cr, was presented in terms of cyclic stress ratio, r/o'0, and mean grainsize of soil, D50. The validity of this correlation was confirmed by the CPT calibrationchamber experiments as well as the laboratory cyclic triaxial tests conducted on medium tocoarse and fine to medium normally consolidated sands at different states of relative density.Besed on the field CPT data at various liquefaction-susceptable sites in Japan and Canada, the predicted cyclic stress ratios causing liquefaction from CPT were also compared withthe laboratory cyclic triaxial tests on undisturbed samples. The proposed CPT-based lique-faction assessment methods agree well with laboratory-measured values.