中文摘要：

针对高原地区边坡冻融灾害,运用有限差分法对高原地区公路边坡进行数值建模,对冻融情况下边坡的破坏形态与失稳机理进行了模拟和解析,利用强度折减法计算分析了不同冻融影响深度及土体抗剪强度变化对冻融边坡安全系数的影响。研究发现：冻融边坡的失稳属于浅层坍塌式的滑坡;随着冻融影响区域加深,边坡坡体受冻融循环的破坏作用范围越大,从而会导致边坡安全系数明显的下降;而冻融造成土体强度参数粘聚力的降低也会影响边坡安全系数。最后,根据冻融边坡的失稳破坏形态与机理,提出了针对性的工程防范措施。

英文摘要：

For the freezing-thawing hazards of slope in the plateau region,numerical modeling of highway slope is established by using finite difference method.Simulation and analysis of the slope failure modes and failure mechanism under freeze-thaw environment are carried out.By using strength reduction method,the influence of different freeze-thaw depth and the change of soil shear strength on the slope safety factor is analyzed.Research shows：freezing-thawing slope instability belongs to shallow collapse type of landslide;with the freezing-thawing effect zone deepen,the damage range of slope suffer from freezing-thawing cycle become more large,which will lead to slope safety coefficient decreased significantly;and the soil strength parameters cohesion reduced the slope safety factor decreases.At last,according to the failure mode and mechanism of freezing-thawing slope,some targeted engineering protection measures are proposed.