中文摘要：

为对加锚复合土钉支护体系的可靠度进行分析与论证,在分析可靠性原理的基础上,从土钉加固机理出发,假定滑移面为圆弧线,对复合支护体系的外部稳定性进行分析;假定滑移面为改进的双折线,对复合支护体系的内部稳定性进行分析;结合工程实例,通过二阶距法对内外部的极限状态功能函数进行可靠度分析。分析与实证结果表明：将可靠度指标用于预应力锚杆复合土钉支护体系的稳定性分析,可以考虑土体的变异性和不确定性,克服了传统的极限平衡理论的弊端;改进的双折线破裂面用于分析复合支护体系的内部稳定性,可考虑土钉支护上部受拉、下部受剪的受力特征,简单合理。研究结果可以为该类工程设计提供较好的理论基础与计算依据。

英文摘要：

To analyze and demonstrate composite retaining system enhanced with soil nails and prestressed anchors,some researches were carried out. In the analysis,a new idea based on reliability principle is presented. Firstly,considering the reinforcement mechanism of soil nailing,external stability of composite retaining system was analyzed based on the assumption of the circular-arcshaped slip surface. Secondly,it was assumed that there was a double-line-shaped slip surface in internal stability study. Lastly,combined with an engineering example,the method of two-order-moment was adopted to analyze the limit state functions of external and internal stability models according to the recommended values of reliability index. The study indicates that the reliability index is suitable used to analyze the stability of composite retaining system,which considers the variability and uncertainty of soil compared with the conventional limit equilibrium theory; that modified doub-le-line-shaped slip surface is simpler and more reasonable for the analysis of internal stability of composite retaining system,because it considers the mechanical characteristic of soil nailed wall,which is tensioned in the upper part and sheared in the lower part. The results can provide theoretical foundations and calculation references for engineering design.