堆积层滑坡由土石混合体构成，具有分布广泛和易发性高的特点。抗滑桩作为治理堆积层滑坡的主要工程措施，其与土石混合体的相互作用是加固堆积层滑坡的力学基础。然而在堆积层滑坡治理实践中，一般采用修正的土体力学参数与极限平衡方法确定抗滑桩设计参数，忽略土石混合体物理力学特性及抗滑桩与滑坡体相互作用过程。这不仅导致抗滑桩设计缺乏科学依据，滑坡治理效果不佳甚至出现安全事故，而且使得无法通过监测滑坡变形定量评价抗滑桩设计的合理性与加固后滑坡的安全性。本项目采用理论分析和数值模拟方法，从土石混合体物理力学特性确定方法入手，以构建抗滑桩与土石混合体相互作用模型为基础，分析计算抗滑桩与滑坡体受力状态，建立基于位移监测数据的抗滑桩与滑坡安全评价方法，利用室内实验与现场监测数据验证其可靠性。考虑相关模型随机误差与土石混合体参数不确定性，构建以经济性、安全性和鲁棒性为目标的抗滑桩设计参数综合优化方法，并进行工程应用。

Colluvial landslide is composed of soil-rock mixtures. It occurs with high frequency and is distributed widely in China. Stabilizing pile is one of the main engineering measures to prevent colluvial landslides. However, the characteristics of soil-rock mixture and interaction between stabilizing pile and the soil-rock mixture are always ignored in practice. Instead, the modified soil mechanical parameters and limit equilibrium method are used to determine the stabilizing pile design parameters. This leads to the loss of scientific basis of stabilizing pile design, or the failure of the stabilized landslide. On the other hand, the rationality of stabilizing pile design and safety of the stabilized landslides cannot be evaluated based on the monitored deformation data of the sliding mass. In the view of the above-mentioned problems, four main tasks are included in this application. Task one, methods to evaluate physical and mechanical parameters of soil rock mixtures are derived, based on which a nonlinear model will be established to quantitatively express the interaction between stabilizing piles and soil-rock mixture. Task two, a displacement data-based model is established to evaluate the safety of stabilizing piles and the landslides. Task three, physical model tests and in-situ monitoring displacement data are used to verify the reliability of models proposed in task one and task two. Task four, the uncertainties of the input parameters are considered in the view of application, an optimal design method is established based on the concept of robust design. In the optimal design method, economy, safety and robustness of the design are considered simultaneously. The results of this application can provide theoretical basis and technical support to the treatment of colluvial landslides.