STRENGTH AND CONSOLIDATION PROPERTIES OF BUSAN NEW PORT CLAYS

The sedimentary environment and the effects of sample disturbance on strength and consolidation properties of Busan New Port clays are examined through microfossils and radiocarbon age analyses and unconfined compression, K₀-consolidated undrained triaxial compression and extension tests and consolidation tests. In this study, only one or two samples, 74 mm in diameter and 100 mm in height, obtained from different depths, are used for the whole series of tests to provide small-sized specimens. The sedimentation rates of Busan New Port clays were (3.7-7.8) mm/year and higher than those for the coastal areas of the USA, Thailand and Japan. The in-situ undrained shear strength and consolidation parameters were estimated using Shogaki's method and compared with those of other test results and evaluated. Busan New Port clays are lightly overconsolidated clays. It can be seen that the consolidation settlements, which were greater than those estimated, were observed in Holocene Busan clay, are caused by the underestimation of the compression index and coefficient of consolidation values caused by sample disturbance.