固结条件与层状结构对互层土力学特性的耦合影响OACHSSCD

Interbedded soil is a special type of structured soil formed by the alternating deposition of different soil types.Its mechanical behavior is strongly affected by the combined influence of the initial consolidation state and the layered structure.Most studies focus on isotropic consolidation.However,the mechanical responses of interbedded soil under anisotropic consolidation have not been systematically investigated.In this study,interbedded soil specimens composed of silty clay and silt were prepared.Undrained triaxial compression tests were conducted under conditions of isotropic and anisotropic consolidation.The effects of the initial consolidation state on the stress-strain relationship,development of pore water pressure,effective stress path,and failure mode were systematically investigated.The results indicate that the mechanical behavior of interbedded soil lies between that of silty clay and silt and is closer to that of silty clay.Anisotropic consolidation significantly enhances soil dilatancy.It suppresses the formation and development of shear bands.As a result,barreling failurebecomes more likely.Both the absolute layer thickness and the thickness ratio jointly control the deformation and strength of interbedded soil.The secant modulus of anisotropically consolidated specimens is generally lower than that of isotropically consolidated specimens.This result indicates that the initial shear stress weakens the shear resistance of the soil skeleton.These findings provide a theoretical basis for geotechnical engineering design in foundations composed of interbedded soil.