【作者】 邓宗伟；

【导师】 冷伍明；

【作者基本信息】 中南大学 ， 岩土工程， 2007， 博士

【摘要】 山区高速公路建设中，对于半挖半填及陡坡路堤处挡土结构物的选择目前一般倾向于摈弃传统的重力式挡土墙，而采用既经济又有更强适应性的轻型支挡结构。但山区地质地形复杂多变，相应而采用的轻型支挡也灵活多样，在这种复杂的边界条件下，支挡结构的受力机理更加复杂，其设计参数的确定也更为困难。目前，该类山区轻型支挡结构的理论研究已远落后于工程实践。因此，对高速公路轻型支挡结构的力学机理进行研究具有重要的理论意义和工程应用价值。本论文以国家重点工程邵怀(山区)高速公路和湖南省交通建设重点试验室开放基金项目为依托，作了以下几个方面的研究工作：1)、对邵怀(山区)高速公路中有代表性的四种轻型支挡结构(预应力锚索桩板墙、悬臂式桩板墙、锚杆式柱板墙和预应力锚索柱板墙)，在现场埋设各种测试元件，进行比较系统的现场测试(包括行车动力试验)。2)、基于双剪统一强度理论和极限平衡原理，推导出一个能够考虑锚索破裂面形状、锚索的倾角、岩土体强度等因素的预应力锚索极限抗拔承载力计算公式。3)、以损伤理论的基本原理及其相应的损伤演化方程为基础，根据锚索荷载传递机理力学方程，推导出考虑岩土体损伤特性的锚索轴力和侧摩阻力沿着锚索长度分布的解析解；基于上述解析解、Mindlin解和Boussinesq解，得出锚索影响范围内土体中任一点的正应力、剪应力以及相应的位移和锚固体与墙面的位移；以上述理论结果为基础提出了锚索合理间距优化设计方法：采用实际工程对上述理论成果进行验证分析。4)、选取应用最为广泛的预应力锚索桩板式挡土墙为分析对象，以FLAC3D为研究工具进行二次开发建立桩、土、锚索、及其界面的耦合分析数值模型，对影响挡墙受力变形的主要参数进行数值仿真分析，提出设计时要考虑的控制因素及可供设计参考的数据资料。5)、根据现场的土压力测试数据、锚杆锚索锚固段与自由段的内力数据、桩的变形数据等对现场的四种挡墙的工作状况进行分析；同时，将每种挡墙的实测数据与其数值计算数据进行了对比分析，归纳出四种轻型支挡结构的受力、变形特征，并提出了静荷载作用下轻型挡土墙的修正设计方法。6)、在行车动力分析方面，基于ANSYS通用有限元程序，针对预应力锚索桩板墙建立了有限元模型，考虑车速、载重、路面不平整度、行车车道等因素，对交通荷载下的轻型挡墙的墙背动态土压力、墙背动态变形、路面动态压应力及路面动态位移等进行计算分析，探讨交通荷载作用下轻型支挡结构的作用机理。7)、选取预应力锚索桩板墙与锚杆柱板墙为分析对象，对这两种挡墙所在位置的路基与墙背处布置的应变式压力盒进行动力测试分析，并将实测数据与数值计算数据进行对比分析，评估了交通荷载对轻型支挡结构的作用与影响，并提出了考虑交通荷载作用时该类挡墙的修正设计计算方法。更多还原

【Abstract】 In mountainous area, when constructing expressway, it is inclined to adopt light retaining system which is economical and adaptability rather than traditional gravity retaining wall. But the geology and topography of mountainous area is more complex, and the styles of the light retaining system are more changeable accordingly. Under this complex boundary condition, the mechanical behaviour of the light retaining system is very complex, and it is very difficult to decide the design parameters too. Nowadays, the study on theory of the light retaining system is far belower to that of the practice. Therefore, the value of the theory and engineering application is great to study the mechanism of the light retaining system. Based on Shuo-Hui expressway—the major project of the state and the opening fund project of the Hunan communication construction control laboratory, some researches had been studied as follows:1) Bury several kinds of testing cells carefully in four kinds light retaining systems (pre-stressed cable sheet-pile, cantilever sheet-pile, anchor post-panel retaining wall, pre-stressed cable post-panel retaining wall) of Shuo-Hui expressway and carry out on site testing systematically (including dynamic testing).2) Based on the unified strength theory, the ultimate equilibrium principle and the shape of rapture of surface, a formula, which takes into account the shape of rapture surface, dip angle of cable, strength of rocks, has been deduced.3) Based on the fundamental principle of defect theory, corresponding damage evolution equation and load transfer mechanism mechanics equation, an analytic solution of anchor cable axial stress and lateral friction stress has been deduced; with this analytic solution, Mindlin solution and Boussinesq solution, the normal stress, shear stress and the corresponding displacement which the cable may affect has been gained; and so do the displacement of grouting and wall; using the above theory achievement, the reasonable spacing optimization method of cable has been gained. At last, the reality projection was used to check the above theory achievements, which show good agreement.4) Choose pre-stressed cable sheet-pile as an example, use FLAC3D program to build the coupling numerical model of pile, soil, cable, and interfaces to calculate and analyze the stress and the strain of retaining wall in different influencing parameter, and offer the main calculating parameters which should be taken into account in design.5) According to the testing data of earth pressure, axial forces of cable, deformation of pile, the working situation of the four kinds of retaining walls has been analyzed; comparing the measured data with numerical computation data of each wall, inducing the features of stress and strain of each wall, and offer the design methods of each wall under static load.6) Based on ANASYS program, choose pre-stressed cable sheet-pile as an example to build FEM model, take velocity, load, unevenness, driving lane into account, the dynamic deformation and dynamic earth pressure of wall, and the dynamic pressure and dynamic deformation of road have been calculated and analyzed, and the mechanism of light retaining system has been discussed under traffic load.7) Take pre-stressed cable sheet-pile and anchor post-panel wall as an analysis object, carry out the dynamic measure of strain pressure cell of wall and roadbed, and comparing the measure data with calculation data. Appraise the effect of traffic load on retaining system, and offer the dynamic earth pressure calculation method under traffic load.更多还原