拓宽路基差异沉降下路面结构受力变形特性及机理研究

发布时间：2018-01-14 10:20

本文关键词：拓宽路基差异沉降下路面结构受力变形特性及机理研究　出处：《长安大学》2015年硕士论文　论文类型：学位论文

【摘要】：高速公路拓宽工程中必然面临地基差异沉降问题,如地基的差异沉降控制不当,路面结构将会受到破坏。目前我国在地基差异沉降对路面结构的力学特性影响方面的研究尚显不足,开展地基差异沉降对路面结构的力学特性及破坏机理研究,对指导高速公路拓宽工程、路面结构设计、预防路面结构破坏及提高路面的使用寿命具有重大的意义。本文依托“国家自然科学基金”项目《大比尺路基拓宽差异沉降模型试验》,以有限元数值模拟为手段,进行地基差异沉降对路面结构的力学特性及破坏机理较深入的研究,本文主要研究内容如下:1.本研究基于大比尺路基拓宽物理模型试验,对试验资料进行重新整理,利用有限元分析软件建立二维数值模型求出路基拓宽地基差异沉降曲线,验证物理模型试验沉降曲线设计的合理性;针对物理模型研究性地建立多个三维数值模型,探讨并确定最合理的物理模型的仿真数值模型,提出了数值模拟关键技术。2.对比分析物理模型的三维数值仿真的计算结果与物理模型试验结果,得出了一致的发展规律;通过有限元数值计算补充了物理模型试验的内容,对在地基差异沉降下路面结构的各个结构层的纵向应力、剪应力及对路面结构层的破坏机理进行分析。3.通过收集资料分析河南省重交通特性,引用国内外得轴载作用下的轮压力学模型,确定车辆荷载图式和车辆荷载横向分布方案;以有限元分析软件为工具,基于拓宽路基差异沉降三维数值模型,进行重交通荷载模拟计算;通过分析差异沉降条件下重交通荷载沥青混凝土和水泥混凝土的数值模拟计算结果,研究路面结构的力学响应规律和破坏机理。
[Abstract]:In the expressway widening project, the differential settlement of the foundation must be faced with, such as the improper control of the differential settlement of the foundation. The pavement structure will be destroyed. At present, the research on the influence of the ground differential settlement on the mechanical properties of the pavement structure is still insufficient, and the research on the mechanical characteristics and failure mechanism of the ground differential settlement on the pavement structure is carried out. To guide the highway widening project, pavement structure design. It is of great significance to prevent the damage of pavement structure and improve the service life of pavement. This paper relies on the project of National Natural Science Foundation "Model Test of widening differential settlement of roadbed with large scale". By means of finite element numerical simulation, the mechanical characteristics and failure mechanism of pavement structure caused by foundation differential settlement are studied deeply. The main contents of this paper are as follows: 1. Based on the physical model test of roadbed widening with large scale, the experimental data are rearranged. Using finite element analysis software to establish a two-dimensional numerical model to find out the subgrade widening foundation differential settlement curve to verify the rationality of the physical model test settlement curve design; Aiming at the physical model, several 3D numerical models are established, and the most reasonable simulation numerical model of physical model is discussed and determined. The key technology of numerical simulation is put forward. 2. The calculation results of three-dimensional numerical simulation of physical model are compared with the results of physical model test, and the development law is obtained. The content of physical model test is supplemented by finite element numerical calculation, and the longitudinal stress of each layer of pavement structure under subgrade differential settlement is analyzed. The shear stress and failure mechanism of pavement structure layer are analyzed. 3. Through collecting data to analyze the heavy traffic characteristics of Henan Province, the wheel pressure model under the action of axle load at home and abroad is quoted. Determine the vehicle load schema and vehicle load transverse distribution scheme; Based on the three-dimensional numerical model of widening the differential settlement of roadbed, the simulation of heavy traffic load is carried out by using finite element analysis software. By analyzing the numerical simulation results of bituminous concrete and cement concrete under heavy traffic load under the condition of differential settlement, the mechanical response law and failure mechanism of pavement structure are studied.
【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】：U416

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