旋喷桩加固客运专线路基挡土墙地基设计应用

研究目的：针对客运专线对挡土墙稳定性和变形要求高的特点,探讨研究挡土墙基底为深厚软弱土层时采用旋喷桩加固的设计计算方法,并提出相应的施工技术要求。研究方法：根据客运专线挡土墙的特点和地基条件,采用复合地基计算理论进行基本参数的计算,并根据计算结果采用压应力扩散理论和实体基础理论对旋喷桩布置和加固深度进行验证。研究结果：基于重力式挡土墙及湿陷性新黄土的特点,在复合地基设计结果基础上,比较实体基础和压应力扩散理论计算的加固深度,为提高客运专线路基挡土墙稳定的可靠度,设计采用实体基础计算理论确定加固深度。研究结论：在地基加固设计中应根据可靠度要求合理选择地基加固深度计算理论,在客运专线重力式挡土墙设计中如果需要大幅度提高承载力,采用实体基础计算理论进行设计可靠度较高。

Design and Application of High-pressure Jet Grouting Pile in Reinforcing the Foundation of Retaining Wall for the Subgrade of Passenger Dedicated Line

Research purposes:The researches are done on the computing methods of design and reinforcement of deep soft weak foundation of retaining wall with high-pressure jet grouting pile and the relative construction technical requirements are presented for the purpose of meeting the high requirements of retaining wall for passenger dedicated line in stability and deformation.Research methods:Based on the characteristics of the retaining wall and foundation conditions of passenger dedicated line,the basic parameters are calculated with calculation theory for composite foundation,and the layout of piles and reinforcing depth are verified with compression stress diffusion theory and solid foundation theory according to the computing results.Research results:Based on the characteristics of gravity retaining wall and new collapsible loess,and computing results of composite foundation,the comparison of the reinforcing depth with solid foundation theory with that with compression stress diffusion is made in order to provide the references to improvement of stability of retaining wall for passenger dedicated line and deciding the reinforcing depth made by solid foundation theory.Research conclusions:The rational computing method of reinforcing depth should be selected according to the requirement of reliability of retaining wall in the course of design and reinforcement of foundation.The solid foundation computing theory should be adopted when it is necessary to largely enhance the bearing capacity of gravity retaining wall for passenger dedicated line.