关键词: 土石混合边坡;接触带软化;含石率;极限分析法;

Abstract: At present，the analysis of the stability of soil-rock mixed slope has not systematically considered the influence of soil softening （shear strength reduction） at the contact zone，but this problem has an important influence on the stability.Therefore，a series of models of soil-rock mixed slope with contact zone with rock contents of 0，10%，20%，30%，40%，50%，60% were generated by stochastic model system.The stabilities of at least 61 soil-rock mixed slopes with contact zone （10 rock distribution positions were considered in each slope model） were calculated by limit analysis method，and the results were compared with those without considering soil softening at contact zone.The analysis results showed that under the same gravel content，the lower limit safety factor of the soil-rock mixed slope with softened soil in contact zone changes little with the different distribution positions of rock blocks.With the increase of gravel content，the sliding surface of soil-rock mixed slope is curved，and the sliding surface passes through the soften contact zone.The soil softening at contact zone of soil-rock mixed slope weakens the influence of rock content and spatial distribution of rock on its safety factor.

Key words: soil-rock mixed slope；contact zone softening；rock content；limit analysis