Effect of Wet–Dry Cycles on the Behaviour of Dredged Marine Clay

Dredging is the process of shifting material from one area of the water environment to another. Dredging produces a very large quantity number of dislodged materials knowns as dredged marine clay, which are commonly considered as waste. Mostly, these soils are dumped into open sea and causes environmental problems. The dredged marine clay exhibits swelling–shrinkage behaviour in response to changes in water content, which are probably affected throughout time by climatic change. The primary objective of the study was to look at how wetting and drying cycles affected the behaviour of dredged marine clay. The swell time graph was drawn for each wet–dry cycle. The void ratio and water content of the specimen were calculated as the number of wet–dry cycles increased, happening at various intermediate phases, from the beginning of swelling to full swelling, and from the beginning of shrinking to the shrinkage limit. Finally, chemical changes on the deformation behaviour of the dredged marine clay during wet–dry cycles were investigated by testing the oedometer reservoir water. The test results showed that after four wet–dry cycles, the soil reaches equilibrium state, in which the vertical deformation during swelling and shrinking were same. The swell-shrink path of each specimen was S-shaped curve.