【作者】 胡会星；

【导师】 苏谦；

【作者基本信息】 西南交通大学 ， 道路与铁道工程， 2013， 硕士

【摘要】 受选线及工程造价条件等方面的限制,出现了大量填方高度较高、覆土较厚的斜坡路基工程,一般的铁路路基支挡结构已无法满足其边坡稳定及上部结构对变形的要求,因此亟需提出一种能够应用于该种特殊地形并能满足其设计年限要求的新型支挡结构。陡坡地段板椅式新型支挡结构综合了桩板式挡土墙和双排抗滑桩两种支挡结构的特点,其不仅能满足较高填方路基对变形的要求,而且能够起到收缩坡脚、减小占地的作用。由于该结构是首次运用于工程实践中,其受力机理及变形特性尚不明确,因此研究板椅式新型支挡结构的受力机理与设计计算是一项十分前沿、紧迫的任务。首先,以叙大线龙山车站板椅式新型支挡结构试验工点为依托,充分调研国内外陡坡地段路基支挡结构研究现状,参照桩板式挡土墙及双排抗滑桩的设计计算理论,将板椅式新型支挡结构分解成桩板墙及门式抗滑桩两个部分分别进行分析计算,提出了适用于斜坡地段板椅式新型支挡结构的计算理论,得到了结构内力的解析解。其次,基于非线性有限元分析软件ABAQUS,建立三维空间有限元模型,分析斜坡地段厚覆土情况下板椅式新型支挡结构内力分布及变形特性。采用罚接触模拟结构中的桩土作用及板土作用,分析桩土作用及板土作用力的分布特性,与理论计算进行对比,验证理论计算的可靠性。此外,对结构建立平面有限元模型,对结构型式、净排间距、锚固深度、横梁刚度以及岩土体弹性模量等敏感参数进行了影响性分析,为今后的结构设计提供一定的理论支撑。最后,基于SAP2000杆系有限元软件,对叙大线龙山车站工点板椅式新型支挡结构进行结构设计,分别从承载板的选择及锚固深度进行设计优化,提出了较为适合的结构尺寸等参数。综上,对板椅式新型支挡结构的受力机理、变形特性及设计计算做了分析和讨论,提出了适用于该结构的一套计算理论,同时对结构的敏感性参数进行了对比分析,为今后该结构的推广运用提供了参考。更多还原

【Abstract】 Limited by route selection and construction cost, lots of steep embankment engineering with high embankment and deep covering soil appear. Oridinary railway supporting and retaining structure can’t meet the requirements of slope stability and deformation requirement of substructure, so a new retaining structure that can apply to this special terrain and meet the requirement of design life is to be put forward. The new board-chair retaining structure on abrupt slope has the features of pile-plank retaining wall and portal double row anti-slide pile. It not only meet the deformation requirement of high embankment, but also play a part in shirnk slope toe and diminish land occupation. Because this structure is firstly applied to project practice and mechanical behavior and deformation characteristic of it are not definite, study on mechanical behaviorand design optimization of new board-chair retaining structure on abrupt slope is a very frontier and urgent task.Firstly, based on board-chair retaining structure of Xuyong-Dacun Longshan station, the domestic and foreign current state of retaining structures on abrupt slope is fully investigated. Referred to calculation theory of pile-plank retaining wall and portal double row anti-slide pile, the board-chair retaining structure is devided to pile-plank retaining wall and portal double row anti-slide pile and caculated. Besides, a new calculation theory which can be applied to board-chair retaining structure on the slope is put forward and analytical solution is obtained.Secondly, ABAQUS which is nonlinear finite element analysis software is adopted and a three dimensional finite element model is established. The internal force distribution and eformation characteristic of new board-chair retaining structure on abrupt slope with deep covering soil are analyzed. The pile-soil and board-soil interactions are simulated by penalty contact. The size distribution characteristic of pile-soil and board-soil interactions is anayzed, which is contrast to theoretical calculation in order to verify the accuracy of theoretical calculation. Besides,2D finite element models are established to simulate the structure. The structure type and clear spacing and anchorage depth and so on which are sensitive parameters are effectively analyzed in order to provide theoretical support for future structure design.At last, based on SAP2000, the board-chair retaining structure of Xuyong-Dacun Longshan station is structural designed. The structure is optimized from bearing plate selection and anchorage depth, and the suitable parameters are put forward, such as structure size etc. Based on upper analysis, the mechanical behavior and deformation characteristic and design optimization of the board-chair retaining structure are analyzed and discussed. A set of calculation theory is put forward and structure size parameters are optimized in order to provide references for popularization and application of the structure.更多还原