中文摘要：

针对露天矿土-岩复合边坡构成及失稳破坏模式的复杂多样性，以依兰露天矿为研究背景，应用极限平衡分析法和强度折减法分别对采场、排土场及二者构成的土-岩复合边坡稳定性进行了分析，优化边坡最终形态，研究其滑坡模式与机制。结果表明：当采场边坡角41°，与排土场相距80m时，复合边坡达最优形态，边坡破坏模式为在自重力作用下，坡面向外蠕变引发的圆弧滑动；极限平衡法简单、可靠，其与强度折减法相结合可弥补各自的不足，结果可靠，便于复合边坡的优化设计。

英文摘要：

Considering the variable constitution and failure mode of soil-rock composite slope, based on the strength reduction method and the limit equilibrium theory, a case study of Yilan open-pit mine is carried out, in which the stability of dump slope, stope slope and composite slope are analysed separately. Then the form of slope is opiimized;with its failure mode and mechanism studied. The result indicates that when angle of stope slope is 41 ~ and distance from dump to stope is 80m, composite slope is in its optimal form;failure mode is circular sliding;the combination of strength reduction method and the limit equilibrium theory to optimize form of slope is reliable and accurate.