Abstract
A laboratory investigation was carried out into anisotropy and time effects on undrained shear behavior of Holocene clay underneath Kobe Airport. A series of undrained compression/extension tests as well as constant-volume direct shear box test both performed using different consolidation time and various shear rates was carried out. The ratio of undrained shear strength to vertical consolidation pressure, Su/σvc was larger in the order of triaxial compression, direct shear box and triaxial extension tests. The Su/σvc value also increased with the consolidation time and with the shear rate. The deformation and strength behavior exhibited an isotach property in which the shear rate was the predominant factor to govern the behavior.
