框架预应力锚杆支挡结构的分析与设计研究

【作者】 周勇；

【导师】 朱彦鹏；

【作者基本信息】 兰州理工大学 ， 结构工程， 2004， 硕士

【摘要】 支挡结构的形式很多，传统的支护方法如重力式挡土墙、衡重式挡土墙、悬臂式挡土墙和扶壁式挡土墙等不仅造价比较高，占用耕地多，而且当挡墙比较高时技术上不可行。随着我国基础建设速度的加快，迫切要求我们对支挡结构理论进行系统的研究，以期获得经济适用的支挡结构形式，这不仅具有重要的理论意义，而且具有重大的现实意义。 框架预应力锚杆支挡结构是近几年新出现的一种轻型支挡结构。本文针对西北地区黄土的特点，对框架预应力锚杆支挡结构进行了理论分析研究。 在以前的挡土墙土压力计算中，设计人员通常采用库仑土压力或朗金土压力理论。这经实践证明并不十分妥当，文中选用目前《建筑边坡工程技术规范》所建议的锚杆支挡结构的土压力计算模型，即认为土压力的分布形状为梯形。 另外，本文提出了框架的立柱、横粱和挡土板的计算单元和计算模型的确定方法，给出了锚杆的支点反力的计算方法。此外，推导了结构稳定性分析和基础埋深设计的表达式，并采用MATLAB语言编制了框架预应力锚杆支挡结构的设计计算程序。如果已知相关设计参数和土体参数，利用该程序可以直接得到设计所需的框架的截面尺寸和配筋、锚杆的直径和长度以及基础的埋置深度。为了方便使用，也可根据此程序编制在各种不同情况下的多工况组合的框架预应力锚杆支挡结构的设计计算表格，供设计时直接查用。 为验证程序的合理性和正确性，文中引入一个工程实例，经程序设计结果和工程实际设计结果的对比表明本文所提出的计算模型合理，计算方法简明实用，所编制的程序是切实可行的，对今后的工程实践能够起到一定的指导作用。本文的分析、计算和研究思路同样可以推广应用于其他土质地区和支挡结构形式。更多还原

【Abstract】 There are many kinds of forms of supporting structure, the costs of traditional supporting methods such as gravity retaining wall, counterweight retaining wall, cantilever retaining wall, buttressed retaining wall and lump stone are relatively high and the area of plough occupied is large, and the technology is infeasible when the retaining wall is high. With the increase of speed of fundamental construction of our country, it is necessary for us to study the theory of supporting structure in detail in order to obtain rational forms of that, which is not only of important theoretical meaning, but also of great reality meaning.Frame supporting structure with pre-stressed anchor bar is a kind of light supporting structure emerging in recent years. Based on the characteristics of collapsible loess in northwest region, the frame supporting structure with pre-stressed anchor bar is analyzed in this paper.In the previous calculation of soil pressure of earth-retaining structure, the Coulomb’s or Rankine’s theory of soil pressure is often adopted, which is demonstrated unadvisable by many engineering projects. The calculating model of soil pressure of anchor bar supporting structure commended by the code named "technical code for building slope engineering" is reasonably chosen.In addition, the calculating elements and the calculating model of vertical column, horizontal beam and retaining plate of frame are proposed in this paper, the solving method of anchor supporting reaction is given out, at the same time, the expressions of analysis of structural stability and embedment depth design of foundation are deduced, and the program of the design and calculation of frame supporting structure with pre-stressed anchor bar is written with the language MATLAB too. If we know the relevant design parameters and soil parameters, using this program can obtain the sectional dimensions and reinforcement of frame, the diameters and lengths of anchors, and the embedded depth of foundation directly. To use it conveniently, we can formulate the design and calculation tables considering many combinations of work conditions under different situations for the frame supporting structure with pre-stressed anchor bar, which are very convenient to engineering designers.To check the rationality and correctness of the above program, a project example is introduced. The comparison between the results of program design and those of practical design indicates that the calculating model is rational, the design methods are simple and utility, and the program is feasible, which can play a certain role for the later practices. The analysis calculation and research thoughtfulness used in this paper can be extended and applied to other regions with different soil features and other forms of supporting structure.更多还原