Research on the United Supporting Structure of Piled Anchor and Reinforced Concrete Internal Bracing for City Deep Foundation Pit under Complex Surroundings

In this paper, according to the hydrogeology and the surrounding of a 20 meters depth city deep foundation pit which has complex surrounding, the united supporting structure of piled anchor and reinforced concrete internal bracing for this foundation pit was proposed based on the reality that some underground space in surrounding of the foundation pit can not be used. Then according to the possible construction process for foundation pit, the stability of the united supporting structure was calculated and analyzed based on the characteristics of piled anchor and internal bracing. And a case project to support a deep foundation pit by using the united supporting structure of piled anchor and reinforced concrete internal bracing was introduced subsequently. The study results show that the 20 meters depth city deep foundation pit stabilizes integrally when the foundation pit is supported by the united supporting structure. The results also show that settlement of the pit's surrounding shallow ground is very small, and water-stop curtain of this pit has good performance on piping resistance. It is also certified that the united supporting structure of piled anchor and reinforced concrete internal bracing can meet to the operating requirements of underground space in surrounding.