The Influence Of Clay Content On Solidification Effect Of Silt And The Influence Mechanism

Much silt occurred in the projects of water engineering, environment engineering and civil engineering. The solidification method is resultful, which dispose the silt and reuse it in earthworks. The silt dredged from different regions had different solidified strength. Clay content of the silt is a main factor which influences the solidified strength. In this paper, the influence of clay content on solidification effect was studied by prepared silt with different clay content which treated by cement, and the influences mechanism of claycontent was discussed.The main contents are as follows:(1) The relationship between unconfined compressive strength and clay contentobtained at different cement content and different curing time were studied by unconfined compressive tests. An optimum clay content (CC_opt) is showed which corresponding to the maximum unconfined compressive strength and minimum failure strain of solidified silt. CCop increases with cement content but rarely affected by curing time.(2) Consolidated undrained triaxial compression tests were conducted to reveal the influence of clay content on cohesion and angle of internal friction of solidified silt. The cohesion increased with clay content, and then began to decrease after clay content beyond a certain value which in accord with the CC_opt obtained by unconfined compressive tests. Angle of internal friction of the solidified silt decreased with increase of clay content.(3) The water transfer for solidified silt with different clay content was studied by a centrifuge and water content tests. Changes of bound water contents during solidification were used to quantify indirectly the amount of gel which contributes to strength of solidified silts. The results showed that variations of bound water contents relative to clay contents were similar to unconfined compressive strength relative to clay contents. It concludes that clay contents which can influence the amount of gel have a significant effect on strength of solidified silts.