Experimental Study On Strength And Deformation Characteristics Of Granite Residual Soil Under Different Stress Paths

Due to the existence of granite residual soil increases the amount of infrastructure development in the region,need to better understand and quantify the nature and behavior of granite residual soil and granite excavation of earthwork,the slope geological hazard control engineering,such as geotechnical engineering technologies designed to provide information.Shenzhen granite residual soil as the research object,using a combination of laboratory experiments and numerical simulation methods,studies of different stress paths on the granite residual soil strength and deformation characteristics.Mechanical test contains granite residual product soil of basic physical properties test,and matrix suction strength test,and compression test Xia of structure deformation features test,and General three axis compression(CTC)test,and decompression compression(RTC)test,and constant average stress compression(TC)test,and K0 merged consolidation compression test,and based on Duncan-Zhang model of numerical calculation and test results intends collection research,surrounding pressure of range for 50kPa~500kPa.Triaxial shear-oriented test to examine stress effects on strength and deformation of granite residual soil.The results of this study can be divided into four parts,as follows:Strength characteristics of granite residual soil under different confining pressure conditions,saturated eluvial soil on granite axial access to tests of shear strength and failure strain was significantly lower than the axial compression test,this result shows that if to replace axial axial compression test done testing,strength will be overvalued.Structural characteristics of granite residual soil deformation under compression,when moisture content is increased,more stable structure parametric curves,and some fortified structure has been destroyed,earth pressure caused by soil bulk density increases will reduce the variability of the granite residual soil structure,increasing structural stability.Under Triaxial paths comparative study on engineering characteristics of granite residual soil and granite residual soil in Hunan destroyed the principal stress difference than Shenzhen destroyed the principal stress difference of granite residual soil and the strain is greater than the strain of granite residual soil in Shenzhen,Hunan granite residual soil strength is slightly less than the granite residual soil strength index in Shenzhen.Of Duncan-Chang model-based numerical study on fitting method and experimental results,when the confining pressure is high,improving Duncan-Chang model can accurately describe the stress-strain of granite residual soil;when the confining pressure is low-voltage State,improved prediction and measurement curve model to more accurately reflect the engineering stress-strain properties of granite residual soil.If in the future the study of granite residual soil in greater depth,this result can be extended to other areas of granite residual soil,as a result of its general discussion and extension of,which this special soil of eluvial soil on granite understanding,mastery and application of relevance and value.