人工冻结地层法施工特大深基坑的数值模拟

Numerical simulation of constructing the huge deep foundation pit by artificially frozen ground method

针对润扬长江公路大桥北锚碇特大深基坑的复杂水文地质条件,提出采用人工冻土墙围护结构。并采用弹塑性有限元法对人工冻土墙围护特大深基坑的施工过程进行了模拟分析,结果表明冻土墙设计厚度5.5m、冻土平均温度-12℃、混凝土衬砌厚度2m、开挖段高2m是安全可靠的,从而为今后的工程设计和决策提供理论依据。

Aiming at the complicated hydrogeologic conditions of the north anchor huge deep foundation pit of Runyang Changjing Bridge, the retaining structure of artificially frozen soil wall is advanced. The numerical simulation of the constructing process of the huge deep foundation pit retained by the artificially frozen soil wall is carried out by using the elastoplastic finite element method. The result shows that the design of the frozen soil wall is safe and feasible with the thickness of the frozen soil wall being 5.5 m,the average temperature -12 ℃,the thickness of the lining concrete 2 m and the excavation height 2 m. The results may be a theoretical basis for engineering practice.