The design of earth structures and foundations resting upon deposits of saturated clay usually requires the estimation of total amount of settlement. The settlement, in general, can be separated into three components; i.e., immediate settlement, primary consolidation settlement and secondary compression. In most cases, it is assumed that the total consolidation settlement is mainly caused by primary consolidation. But in some cases, the secondary compression has notorious effects on the structures.
Generally, the rate of secondary compression is given by Cα (change in void ratio per log time). The Cα is influenced by several factors, e.g., OCR, consolidation pressure, earth pressure ratio(K), etc. The objective of this study is the examination of the above influence factors through experimental approach such as oedometer test and triaxial test. Consolidation tests were conducted on undisturbed and remolded samples collected from Gwangyang Bay area.
According to the test results, Gwangyang Bay clay has a high potential secondary compression and the rate of secondary consolidation is independent of load increment ratio. It is, however, dependent on OCR, consolidation pressure, remolding, earth pressure ratio, and preloading. Especially, the preloading reduces the rate of secondary consolidation, but increases the amount of secondary consolidation settlement during the lifetime of structures.
