目前涉及岩土体不均匀性的岩土问题可靠度分析大多只考虑岩土体的固有变异,即岩土体特性参数的不均匀性,未考虑涉及不同岩土体材料的地层变异。地层变异在实际滑坡中广泛存在,其表现为不同类型岩土材料(如黏土、粉土、砂土)的互相嵌套,或一种类型岩土体在另一种较均质岩土体中的随机分布。为此,提出了利用钻孔资料评估考虑地层变异时边坡稳定不确定性的分析方法。根据已有钻孔资料设计了不同的钻孔布置方案,建立了表征地层变异的马尔可夫链模型,采用有限元强度折减法进行边坡稳定性分析,探讨了钻孔布置方案对评估边坡稳定安全系数和失效概率不确定性的影响。以澳大利亚珀斯市钻孔资料为例,分析了所提方法的有效性。结果表明,钻孔布置方案对边坡稳定安全系数和失效概率的不确定性评估有重要影响。考虑地层变异时,边坡稳定安全系数可以用Johnson分布来描述;边坡稳定安全系数统计量和失效概率不一定随钻孔数量增加而单调变化,边坡影响区域以内钻孔对评估边坡稳定安全系数的不确定性最为有效;当钻孔数目逐渐增加时,边坡安全系数均值逐渐收敛至精确值。 At present, reliability analysis of rock and soil problems involving inhomogeneity of rock and soil mostly only consider the inherent variation of rock and soil, that is, the inhomogeneity of the characteristic parameters of rock and soil, and not consider the variation of strata involved in different rock and soil materials. Stratigraphic variations are widespread in real landslides, as evidenced by the nesting of different types of geomaterials (eg, clay, silt, sand), or of one type of rock mass in another, more homogeneous rock mass Random distribution. Therefore, an analysis method of using the drilling data to evaluate the stability of slope stability considering formation variation is proposed. According to the existing borehole data, different drilling layout schemes were designed, Markov chain model to characterize the formation variation was established, and the stability analysis of slope was carried out by finite element strength reduction method. The influences of drilling layout on slope evaluation Stable safety factor and uncertainty of failure probability. Taking the borehole data of Perth, Australia as an example, the effectiveness of the proposed method is analyzed. The results show that the drilling layout scheme has an important influence on the evaluation of slope stability safety factor and failure probability uncertainty. When considering the variation of formation, the slope safety factor can be described by Johnson distribution. The statistics and failure probabilities of slope stability safety factor do not necessarily change monotonically with the increase of the number of boreholes. The uncertainty of the safety factor is most effective. When the number of drilling holes increases gradually, the mean value of slope safety factor gradually converges to the exact value.