单支点桩锚土钉联合支护在云南某深基坑中的应用

Application of Single Fulcrum Pile-anchors and Soil-Nails Supporting System for Deep Foundation Pit in Yunnan

在城区对深基坑进行支护时,因地质和施工条件复杂,单一支护方式往往难以满足基坑的变形与稳定性要求。单支点桩锚土钉联合支护结构作为一种复合优势明显的组合支护方式,可有效控制基坑变形、减少施工难度。但目前该方法的设计理论尚未成熟,限制了其工程应用推广。利用工程类比法,基于前人研究的土压力分配模型,结合规范及相关研究理论将其运用于云南某深基坑支护设计中,分别就桩锚结构及土钉结构部分进行了设计计算,并根据规范要求对其进行了安全性验算,确定了该方法的适用性及此设计思路的可行性。

Due to complicated geological and construction conditions in urban district,single support methods usually can＇t meet the deformation and stability requirements of deep foundation pits.As a competitive combined supporting method,single fulcrum pile-anchor and soil nailing supporting system can effectively control deformation of foundation pit and reduce the construction difficulties.However,this method of design is not yet mature, which limits its promotion.Therefore,base on engineering analogy method,soil pressure distribution model of related research and regulations,the method mention above was applied to a deep foundation pit supporting design in Yunnan province.In this paper, the pile-anchor and soil-nailing part was designed respectively,and then the safety checking was carried out in accordance with specifications,thereby the applicability of the method and the feasibility of the design were identified initially.