Mechanical properties and modified Duncan-Chang model of lignin-rice straw improved soil
Lignin has the effect of cementing soil mass,and rice straw fiber also has the ability to improve the shear strength of soil mass.However,there are relatively few studies on the use of lignin and straw to improve red clay.In this paper,through the consolidation undrained triaxial compression tests,the stress-strain curves of lignin-rice straw improved soil under different confining pressures and different lignin contentsare obtained.Based on these curves,the mechanical properties of the improved soil are studied,a modified Duncan-Chang model is established,and the influence of lignin content on the model parameters is analyzed.The research results show that the principal stress difference of the improved soil mass first increases and then decreases with the increase of lignin content,and reachies its maximum value when the lignin content is 0.7%.The initial deformation modulus Ei,ultimate deviator stress(σ1-σ3)ult,cohesion c,internal friction angle φ,and parameter K of the improved soil mass first increase and then decrease with the increase of lignin content.The parameter n increases with the increase of lignin content,while the failure ratio Rf is not significantly affected by lignin content.
ligninfiber reinforced soilred claytriaxial teststress-strain relationshipmodified Duncan-Chang model
万方数据
维普
