土钉支护整体稳定验算与局部稳定验算间的关系

针对现行基坑支护规程中关于土钉支护的设计验算,讨论了其整体稳定验算和局部稳定验算的必要性问题。研究表明:对于一般土钉支护,当土钉的破坏服从理想弹塑性或硬化弹塑性规律时,只需进行整体稳定验算,但满足局部稳定验算可使设计方案更为合理;当土钉的破坏呈软化规律时,整体稳定验算和局部稳定验算都是必要的,但当土体相对黏性较大时,只需按局部稳定验算来设计土钉支护结构,无需进行整体稳定验算。

RELATIONSHIP BETWEEN GLOBAL STABILITY AND LOCAL STABILITY ANALYSIS OF SOIL NAILING

Based on the design method of soil nailing in the current codes for excavation support,the need of global stability checking and local stability checking for soil nailing in design was discussed.It was shown that only global stability checking was necessary when the failure of the soil nailing obeyed the law of elastic-perfectly plastic or hardening.However,local stability checking could make the design more reasonable.Global stability checking were local stability checking were both needed when the failure of the soil nailing possessed of a softening nature.But local stability checking was sufficient when the cohesion of the soil was relatively large.