应力路径对固结排水条件下饱和原状黄土

在轴向加载、径向卸载和轴向卸载、径向加载二种类型的等应力比应力路径下,对杨凌饱和原状黄土进行K0固结排水三轴剪切试验,探讨了应力路径、固结围压等对饱和原状黄土的变形及强度特性影响的规律.研究表明,应力路径类型对其变形及强度特性有明显的影响;在二种类型等应力比应力路径下,体积变形皆表现为剪缩性,且固结围压及应力路径类型相同时,体应变随应力路径的变化呈现出规律性的变化;对于同一类型的等应力比应力路径,破坏强度值因应力路径的变化而异,但不同应力路径下临界状态线是唯一的,挤伸破坏时抗剪强度要比压缩破坏时低.

Influence of stress path on deformation and strength characteristics of saturated intact loess under drainage condition

The drained triaxial consolidation shear test of saturated intact loess under two types of stress path including axial loading radial unloading and axial unloading radial loading with constant stress ratio is carried out to investigate the effect of stress path and confining pressure on deformation and strength characteristics of the loess. The result shows that the stress paths significantly influence the deformation and strength characteristics. Under both types of stress path with constant stress ratio, the volume contraction occurs. The volumetric strain has a disciplinary change as stress path changes under the same consolidation condition and the same type of stress path. For the same type of stress path with constant stress ratio, the failure strength is different under different stress paths, but the critical state line is unique. The shear strength of extension failure is less than that of compression failure.