Abstract: Researching the progressive failure of bedding rock landslide with weak interlayer, which is a common geological disaster, is of vital significance to the protection and treatment of landslides. In the light of the strain softening characteristics of weak interlayer, the differential equation reflecting the progressive failure process of bedding rock slope with weak interlayer under excavation condition is derived, and the process and stages of progressive destruction are revealed through theoretical analysis. Compared with the calculation results of Mohr-Coulomb constitutive model, the strain-softening Mohr-Coulomb constitutive model reflects more accurately the progressive failure of slope with weak interlayers, which is validated rational by an engineering example. The progressive failure of bedding rock slope with weak interlayer can be divided into three stages: initial deformation, constant speed deformation, and accelerated deformation. Under excavation condition, shear failure first occurs at the slope toe, and extends continuously to the top of slope along the weak interlayer; meanwhile, tensile failure occurs on the top of the slope. The overall failure of the slope is in a slip-crack mode.

Key words: bedding rock slope, weak interlayer, progressive failure, strain-softening, Mohr-Coulomb model