Investigation on rheological and strength characteristics of cement-treated dredged materials

Beneficial use of dredged materials (DMs) obtained using the hydraulic dredging technique is a challenge since they behave like slurry with very high-water content. This paper presents an experimental study on the impacts of initial water contents and cement content on flowability, viscosity, and strength characteristic of cement-treated DM samples at high-initial water contents. A series of flow, viscosity and unconfined compressive strength tests were conducted on cement-treated DM specimens with various initial water contents and cement contents. Tests results showed that the value of slump flow increases almost linearly with increasing initial water content. The effect of cement content on slump flow for specimens at various initial water contents follows the same decreasing trend. Fresh mixtures of cement-treated DM specimens behave like Bingham plastic. Dynamic viscosity reduces with the increase in initial water content and the decrease in cement content. Slump flow reduces with the increase in viscosity or yield stress following a power trend line. All cement-treated specimens curing for 28 days exhibit strain-softening behavior. Unconfined compressive strength reduces as the initial water content increases and cement content decreases. A quantitative equation was developed to estimate the compressive strength as a function of initial water content and cement content.