Abstract:The silts dredged from ocean,lake and river always have different clay contents which lead to different strength of solidified silts. Silts with different clay contents are prepared;and the influence of clay content on mechanical properties of solidified silt is tested. It is discovered that different clay contents have remarkable influence on the mechanical properties of solidified silt. When the cement content is 5.0%,the strength of the solidified soil increases with the clay content increasing. When the cement content is above 7.5%,an optimum clay content(CCop) is showed,which is corresponding to the different cement contents. When the clay content is equal to the CCop ,the maximum unconfined compressive strength and the minimum failure strain of solidified silt can be obtained. The numerical value of CCop increases with cement content increasingly lifting,but freatment time has no effect on it. The triaxial experiments show that the solidified silt with CCop has the maximum cohesion index,however,the angle of internal friction decreases with the increase of clay content. At the same time,the stress-strain relationship of solidified soil with different clay contents is also researched. The results show that,if the cement content is below 5.0%,the stress-strain relationship of solidified soil behaves ideal elastoplastic characteristics;if the cement content is above 5.0%,the stress-strain relationship behaves brittle failure characteristics,meanwhile,there is a peak value. Moreover,the failure strain decreases earlier but increases later with the clay content rising,while the clay content is up to the optimum one,the failure strain approaches to the minimum. So solidified soil will behave the maximum unconfined compressive strength and the minimum strain. The results have great significances for the design of solidified agent in practical engineering.