Study On Mechanical Properties And Differences Of Artificially Prepared Structural Loess

Due to the nonhomogeneity,unisotropy and difficulty in sample preparation of undisturbed loess,Therefore,in this paper,a small amount of cement,lime and RoadyesTM are added to the remolded loess as binders,The mechanical properties and differences of artificially prepared structural loess were studied by adding different binders.Using direct shear test,this paper studies the effects of different binders and binders content on the shear stress-displacement curve,shear strength parameters and structural strength of artificially prepared structural soil,and selects the binders content with similar structural strength to natural undisturbed loess to prepare structural soil,so as to further study the differences of mechanical properties of structural soil caused by different binders.Based on the confining compression test,the effects of different binders and water content on the compression deformation characteristics and collapsible deformation characteristics of artificially prepared structural soil were studied.By introducing the void ratio structural parameter mp to establish the relationship between the mp of three different structural soils and the test variables.Through the triaxial consolidated drained shear test,the effects of different binders and water content on the stress-strain relationship,volume strain characteristics and stress structural parameter mσ evolution of artificially prepared structural soil are analyzed.It is found that in a large range of water content,the variation trend of cohesion and peak stress structural parameters of structural soil with RoadyesTM as binders and natural undisturbed soil with water content is the closest.By introducing the mσ to normalize the three kinds of artificially prepared soils,the constitutive relations of three structural soils considering structure are established.Through dynamic triaxial test,the effects of different binders and water content on the backbone curve,dynamic modulus and damping ratio of artificially prepared structural soil are studied.The dynamic shear modulus and damping ratio of three kinds of structural soil are fitted by improved Hardin-Drnevich model,and establish the mathematical relationship between them,and the differences of dynamic characteristics of artificially prepared structural soil are discussed.To sum up,through laboratory tests,the differences of compression collapse deformation characteristics,stress-strain relationship,strength characteristics,structural characteristics of structural soil prepared with three binders under static action are analyzed;The difference of dynamic modulus and damping ratio under dynamic action.The study shows that the mechanical properties of structural loess prepared by RoadyesTM as binders are similar to those of undisturbed loess in a large range of water content,which provides a theoretical basis for the preparation of artificial structural loess in the laboratory.