基于一阶二次矩阵的寒区土质高切坡稳定可靠度分析

以寒区土质高切坡为研究对象，构建了寒区土质高切坡浅层滑动失稳模型，基于极限平衡原理和可靠性原理，建立了寒区土质高切坡的可靠指标和失稳概率计算方法。以G580线和田至康西瓦公路段K86+780～K86+840土质高切坡为例进行了寒区土质高切坡可靠度计算，并分析了各种因素对寒区土质高切坡失稳概率的影响规律。结果表明，该方法建立的可靠指标与失稳概率计算方法可以用于寒区土质高切坡稳定性分析，并且当融化深度大于1.4 m时高切坡失效概率迅速升高，1.4～2.1 m失效概率增长74.4 %，当融化深度大于2.1 m时坡体处于不稳定的状态;当土质高切坡粘聚力从8 kPa增长到14 kPa的时候，失稳概率降低约88.4 %,稳定系数增长0.45;当土质高切坡内摩擦角从15 °增长到23 °时，失稳概率降低约15 %，稳定系数增加约0.07;当土质高切坡坡率由0.5增加到0.8时，边坡失稳概率由26.5 %增长到61.4 1%，坡率到0.8时为峰值，大于0.8之后失稳概率逐渐减小，到1.5时失稳概率降低至25.2 %，降低约36.21 %。

Stability and reliability analysis of high cut slope in cold region

Based on the principle of limit equilibrium and the principle of reliability, the reliability index and the calculation method of instability probability of soil high cut slope in cold region are established. Taking the K86+780 ~ K86+840 soil high cut slope of the highway section from hetian to kangxiwa of G580 line as an example, the reliability calculation of soil high cut slope in the cold region was carried out, and the influence law of various factors on the instability probability of soil high cut slope in the cold region was analyzed. The results show that the reliability index and instability probability calculation method established by this method can be used to analyze the stability of high cut slope in cold region. The failure probability of high cut slope increases rapidly when the melting depth is greater than 1.4 m, and the failure probability of 1.4-2.1 m increases by 74.4 %. When the melting depth is greater than 2.1 m, the slope is in an unstable state. When the cohesive force of soil high-cut slope increases from 8 kPa to 14 kPa, the instability probability decreases by about 88.4 % and the stability coefficient increases by 0.45. When the soil cut high slope Angle of internal friction from 23 °, 15 ° growth to decrease the instability probability by 15 %, the stability coefficient increased about 0.07; When the slope coefficient of soil high-cut slope increases from 0.5 to 0.8, the slope instability probability increases from 26.5 % to 61.41 %; when the slope coefficient increases from 0.8, it is the peak value; when the slope coefficient is larger than 0.8, the instability probability gradually decreases; when it reaches 1.5, the instability probability decreases to 25.2 % and 36.21 %.