高速铁路新型桩承式加筋低路堤荷载传递机理与动力稳定性研究

项目名称： 高速铁路新型桩承式加筋低路堤荷载传递机理与动力稳定性研究

项目编号： No.51508478

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 建筑环境与结构工程学科

项目作者： 黄俊杰

作者单位： 西南交通大学

项目金额： 20万元

中文摘要： 高速铁路新型桩承式加筋低路堤结合了桩承式加筋低路堤传统技术和挂网技术的优点，在不良地基处理中具有广阔的应用前景，由于该结构将高强度格栅网固定于桩帽，加之受动力荷载作用，使其受力和变形行为较为复杂，目前设计仍缺乏系统的理论依据。为此，以高速铁路新型桩承式加筋低路堤为研究对象，通过模型试验、数值计算和理论分析等手段，分析不同桩间距的新型桩承式加筋低路堤在填筑过程中填料颗粒细观运动规律，研究垫层双层加筋网张拉膜效应和土拱效应及其相互影响机制，揭示新型桩承式加筋低路堤结构荷载传递机理；考虑上部荷载与地基土固结耦合效应，研究新型桩承式加筋低路堤受力与变形随时间的变化规律，揭示新型双层加筋网张拉膜效应和土拱效应时变规律；考虑动力流固耦合效应，研究新型桩承式加筋低路堤动态响应指标和累积变形的变化规律，提出其动力稳定性分析方法，评价其动力稳定性。该研究成果可为高速铁路新型桩承式加筋低路堤设计提供理论依据。

中文关键词： 高速铁路；新型桩承式加筋低路堤；双层加筋垫层；荷载传递机理；动力稳定性

英文摘要： The novel geosynthetic-reinforced and pile-supported low embankment combining the advantages of traditional pile-supported embankment and new suspended net technology has good application prospect in the treatment of poor ground of high speed railway. The force and deformation behavior of the structure in which high strength geotechnical grille is fixed on the pile cap under dynamic load is complicated, and there is currently a lack of the systematic theoretical basis for design of this structure. Therefore, through the means of model test, numerical calculation and theoretical analysis, the microscopic motion law of filler particle when novel geosynthetic-reinforced and pile-supported low embankment with different pile spacing is filled is analysed. Then tensioned membrane of new double geosynthetic-reinforced cushion, soil arching effect in the embankment and interplay mechanism are studied to reveal the load transfer mechanism of the novel embankment structure. Considering the coupling effect of upper load and soil consolidation, the time variant characteristics of the force and deformation of the novel embankment structure are researched to demonstrate the evolution law of the tensioned membrane and soil arching effect of novel double geosynthetic-reinforced structure. Considering the dynamic fluid-solid coupling effect, the dynamic response index and variation law of macroscopic accumulated deformation of the novel embankment structure are researched, and analysis method of dynamic stability for the novel embankment is presented, so that to evaluate its dynamic stability. The research results can provide a theoretical basis for the design of the novel geosynthetic-reinforced and pile-supported low embankment.

英文关键词： High-speed railway;Novel geosynthetic-reinforced and pile-supported low embankment;Double reinforced cushion;Load transfer mechanism;Dynamic stability