Abstract
The authors investigated the strength ratio causing liquefaction of diluvial sandy ground based on laboratory tests. As a result, it is clarified that the strength ratio causing liquefaction of diluvial sandy graound was lager than it of alluvial sandy ground. Because, the diluvial sandy ground was appeared the cohesion by the effect of an age. And the level of increase of strength ratio causing liquefaction was depended on it's the fine fraction content ratio.
