Cementitious Soil Preparation Test And Performance Analysis

Cemented soil dam is a new type of dam which is environmentally friendly and has the characteristics of overtopping slow collapse and overtopping non-collapse.The damming material(cemented soil) used in this dam is generally the mixture of natural soil and cement and/or lime.Therefore,the preparation of cemented soil with good performance is very important for the construction of reservoir dams in China.The soil material used in this study is silty clay from Harbin,and the cementing materials are cement,lime and fly ash.This paper refer to the domestic and foreign literature related to the cemented soil preparation,design the reasonable configuration scheme,determine the configuration scheme with single doped gelled material modified clay powder,modified double mixing cement materials silty clay and three mixed gelled material modified silty clay,and then determined by each preparation program soils compaction test and the maximum dry density,optimum moisture content of samples according to the maximum dry density and optimum moisture content and mechanical properties test,unconfined compressive strength test and triaxial compression test and endurance test(under the environment of the dry-wet circulation,the freeze-thaw cycle level of physical and mechanical performance test).Through the analysis of the test results,the following main conclusions can be drawn:(1)The addition of cementitious materials improves the mechanical properties of silty clay.In the silty clay modified by single-,double-and three-admixture,the best methods to improve its performance are single-admixture of 6% cement,double-admixture of 4% cement and 2% lime,three-admixture of 3% cement,1.5% lime and 1.5% fly ash.(2)The volume deformation rate,water content,mass loss rate and unconfinedresistance of silty clay mixed with single 6% cement,double 4% cement and 2% lime,and three 3% cement,1.5% lime and 1.5% fly ash eventually become stable with the increase of The Times of dry-wet cycle or freeze-thaw cycle,and have certain dry-wet and frost resistance.(3)the combination of mechanical properties and durability test results,it is concluded that the best preparation method is double mixing 4% cement and lime 2%,followed by three 3% cement,1.5% lime and 1.5% fly ash,its compressive strength without side all satisfy the standard of the cemented soil dam,but three mixed gelling material modified silty clay is more economical and ultimately determine the optimal solution of silty clay modification for the three mixed cementing material,the proportion of 3% cement,1.5% lime and 1.5% fly ash,cemented soil preparation for our businesses to provide the certain reference significance.