Application And Research Of The Thick-layer Soft Soil Foundation Treated By The PHC Pile

High-speed, convenient and comfortable railway system is an important indication of the developed countries ,many developed countries in the world now have built their own Inter-City high-speed railway networks. The roadbed of high-speed railway should be of high strength, rigidity, and good stability and durability, the railway design parameters must be maintained at the required standard range during the operation period. Therefore the high-speed railway is necessary to strictly control the deformation of the subgrade.In the past, drainage consolidation method and cement mixing pile method were often used to reinforce the soft soil roadbed of the railway. However, according to the control standards of the settlement of high-speed railway roadbed ,the PHC pile(Prestressed Concrete Pipe) composite foundation reinforcement method is more reasonable.In this article, the following aspects of the PHC pile composite foundation reinforcement method were analyzed:Firstly, based on the data acquired by the field test of layered settlements, the settlement regulation of the thick-layer soft soil treated by the composite structure of pile net was analyzed. Also, the prediction was taken to the final settlement utilizing two calculation models. Meanwhile, since the settlement by prediction is far less than that required by the standard, so that the cost will be reduced through the optimization of the design parameters. After that, according to the mechanism of the composite structure of pile net, the settlement was calculated using multiple calculation methods, and the results were compared to the experimental ones. By this, the settlement calculation method of the thick-layer soft soil foundation treated by the composite structure of PHC pile net. In addition, the FEM software was employed to simulate and analyze the influence of each parameter, and the parametric optimization suggestion was presented. In the end, the control method concerning construction technology and quality was introduced.