Numerical Simulation Analysis Of Double-row Piles Composite Anchor Supporting System

The requirements of retaining structure is promoting day by day in deep excavation engineering with the popularizing of high-level, super high-rise building and the increased depth of the foundation ditch, the traditional and single supporting structures can not meet demand. The multiple compound supporting system composed by different single support is the research focus and the major development direction of foundation supporting in our country at present.Anchor retaining structure is one of the most frequent methods used in retaining structures. The double-row pile supporting has had many successful application exanples with the further research gradually,and achieved good supporting effect, but double-row pile composite anchor is a new type of composite support structure.The supporting structure consists of double-row pile and anchor by the reasonable design constitute a whole,it is the double-row pile composite anchor supporting system,the double-row pile and anchor syetem can bring into play their respective technical advantage bsetly. The double row pile composite anchor not only has the good economic benefits, but also has good performance in reducing deformation, shortening the period of the engineering,has had successfully applied example in zhengzhou region, but the theory and construction of its force and deformation research remains deficient. Based on previous researches,the three-dimensional numerical simulation has brought out to the double-row pile composite anchor supporting system in this paper, the main research method and the results are as follows:(1) The overall horizontal and vertical displacement level of the pit and retaining structure, as well as the uplift and settlement law of soil during the excavation accords to pit excavation rule, through the supporting structure lateral curve we concluded that double-row pile composite anchor can get better effects in limiting the lateral displacement of the foundation pit.(2) Analysis the pile body stress change rule of double-row piles during the excavation process, comes to the conclusion that double-row pile and anchor can work coordination perfectly,the anchor bring significantly improve to the stress of the situation in which the force more reasonable of the double-row piles, the front pile is the main force components.(3) The distribution of the soil nailing axial force according with pure soil nailing rule in the upper slope soil nailing support part, the working mechanism of soil nailing can explain different positions of the soil nailing axial force.(4) The supporting syetem is reasonable and practical considering the measured data of a specific engineering examples.