能量法在土钉支护结构分析中的应用

ANALYSIS ON SOIL-NAILED RETAINING STRUCTURE USING ENERGY METHOD

利用能量法从功率平衡的角度定量的给出了整体支护情况下土钉支护结构的极限开挖深度Hu的公式,得到了每步开挖下的安全系数ki及每步开挖深度Dhi;同时将土钉对土体的加固约束作用等效为土体的粘聚力增量,得到了似粘聚力Dc的公式。分析了支护结束极限情况下和逐步开挖情况下土钉支护结构主要设计参数对极限开挖深度iHu、安全系数ki、每步开挖深度Dhi、似粘聚力Dc的影响规律,为土钉支护结构的设计提供了一定的依据。

Soil nailing is a widely used means for slope stabilization in the last two decades. The traditional limit equilibrium method in the design of soil-nailed systems can not give the maximum depth Hu for soil-nailed retaining structure and excavation depth δhi, of each step. Based on energy method and power equilibrium equation, the formula of limit excavation depth of soil-nailed retaining structure is presented, and a new safety factor ki of each step and δhi, of each step are also established. Pseudo cohesion δC is obtained by taking the effect of reinforcement and restriction soil nail as the increasing soil cohesion. The main influence factors of soils and soil nails and the variation rules of limit excavation are analyzed. All these can be used for references to the design of soil-nailed retaining structures.