预应力格构锚固体系模拟试验研究

发布时间：2018-04-25 13:18

本文选题：预应力 + 锚索格构梁　；参考：《长安大学》2015年硕士论文

【摘要】：近年来,国家基础设施建设发展迅猛,随着公路、铁路,城市建设工程的大规模开展,不可避免地要进行边坡开挖,由于处理不当,酿成了许多人工滑坡,目前对于滑坡防治的方法众多。格构梁锚固体系作为一种新型滑坡防治技术,具有施工便捷、造价合理及安全可靠等优点,搭配植被还有美化坡面的效果,因而在近年的滑坡防治工程设计中被广泛应用。为了研究框架梁锚固体系中框架梁-锚索-岩土体复合结构的受力特点,以及框架梁之间、梁与锚索之间的相互作用机理,为后续研究提供参考,同时为工程设计提出合理化建议,本文作了以下具体研究工作:1)以课题组承担的格构锚固大型物理模型试验[1]为研究背景,结合物理模型试验的设计方法和实测参数,首先用ANSYS软件建立了滑坡基本模型,合理划分模型网格,再利用FLAC-3D(岩土数值模拟软件)对锚索-格构支护体系进行三维数值模拟计算。2)开展了滑坡基本模型试验研究,在基本模型试验的基础上,对所进行的非预应力锚索格构试验进行模拟,对获得的模拟试验数据进行分析。随后对锚索施加预应力,分别对正方型格构-正方形截面、正方型格构-矩形截面、矩型格构-正方形截面、矩型格构-矩形截面等不同截面尺寸的锚索格构进行模拟分析。3)在以上格构形式研究的基础上,又对预应力锚固下的菱型格构、人字型格构以及拱型格构做了计算分析,研究了各格构类型随滑坡作用时的应变分布、应力分布规律,重点分析了锚索单元和格构梁单元的受力规律、变化特性以及破坏模式,预应力损失,同时分析了人字型格构和拱型格构梁所受的扭矩。4)将模拟计算结果与解析法所得格构梁内力计算结果、物理模型试验结果进行分析验证。对各计算结构汇总分析,阐明了格构梁最易破坏点,锚索所受最大轴力位置等关键问题,为实际工程设计提出了一些建议。
[Abstract]:In recent years, the construction of national infrastructure has developed rapidly. With the large-scale development of highway, railway and urban construction projects, slope excavation is inevitable. As a result of improper handling, many artificial landslides have resulted. At present, there are many methods for landslide prevention. As a new type of landslide prevention and control technology, lattice beam Anchorage system has the advantages of convenient construction, reasonable cost, safe and reliable, and so on. It has been widely used in landslide prevention and control engineering design in recent years because of the combination of vegetation and the effect of beautifying the slope surface. In order to study the mechanical characteristics of frame beam-cable rock-soil composite structure in frame beam Anchorage system, as well as the interaction mechanism between frame beam and anchor cable, this paper provides a reference for further research. At the same time, some reasonable suggestions for engineering design are put forward. The following specific research work is done: 1) based on the large-scale physical model test of lattice Anchorage undertaken by the research group, the design method and the measured parameters of the physical model test are combined. At first, the basic landslide model is established by ANSYS software, and the model grid is reasonably divided, and then the basic landslide model test is carried out by using FLAC-3D (geotechnical numerical simulation software) to carry out three-dimensional numerical simulation calculation of anchor cable lattice support system. On the basis of the basic model test, the unprestressed cable lattice test is simulated, and the obtained simulation test data are analyzed. Then the prestressed cable is applied to square lattice-square section, square lattice-rectangular section, rectangular lattice-square section, On the basis of the study of the above lattice form, the rhombohedral lattice structure, the herringbone lattice structure and the arch lattice structure under prestressed Anchorage are calculated and analyzed. The strain distribution and stress distribution of each lattice structure type with the action of landslide are studied. The stress law, variation characteristic, failure mode and prestress loss of anchor cable element and lattice beam element are analyzed emphatically. At the same time, the torsion. 4) the internal force of the lattice beam obtained by the analytical method and the simulation results are analyzed and verified by the physical model test. Based on the summary and analysis of each computational structure, some key problems, such as the most easily damaged point of lattice beam and the position of maximum axial force of anchor cable, are clarified, and some suggestions for practical engineering design are put forward.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P642.22;TU476

【参考文献】