【作者】 谷复光；

【导师】 王清；

【作者基本信息】 吉林大学 ， 地质工程， 2011， 博士

【摘要】 近年来,随着我国高速公路的飞速发展,出现了越来越多的高填方路基。由于我国幅员辽阔,高速公路建设过程中遇到的地质问题差异较大,所以不能简单地将某个地区积累的经验用于全国。而高填方路基的变形破坏是路基工程质量通病之一,其原因十分复杂,它不仅与路基填土密实度和边坡高度有关,也与路基填料性质、边坡坡度、地基性质、水文状况、路基压实、设计标准,施工方法等有关。高填方路基的变形破坏,在工程中主要表现为:路基填土开裂、路基滑动、边坡坍塌和与之有关的路基结构破坏、路基整体下沉或局部沉降。高填方路基一旦发生变形破坏,其处治是相当困难的,因此必须对此引起高度重视。为了防止高填方路基产生过大沉降和变形,进行高填方路基沉降和变形的深入研究就显得更加有意义。为此,针对吉林省出现的高填方路基,开展高填方路基沉降观测和沉降规律的研究就有其必要性。通过对实测的路基沉降观测资料进行整理分析既可以对后期沉降进行预测,也可以总结高填方路基的沉降变形规律,据此可以指导进一步的优化设计,改进有关的施工工艺,直接为公路设计施工决策提供科学依据。通过大量查阅相关资料,综述了国内外高填方路基沉降问题的研究历史及现状。回顾了路基沉降的理论分析方法及常见的实用计算方法,讨论了高填方路基的沉降机理及传统计算方法存在的问题和不足之处。针对这些不足,在结合室内试验结果的基础上,分析了高填方路基的沉降机理,并以大型有限元分析软件ANSYS为手段,选用适合于岩土类材料的D-P本构模型,对高填方路基沉降问题进行平面应变弹塑性数值模拟分析。利用数值模拟方法的灵活性,分别对填筑高度,路基边坡坡度,采用轻质填筑材料,深浅层地基处理,路基材料压实度等因素对于高填方路基的沉降影响进行研究,给出变化规律。选定三条吉林省省内典型路段的路基填土取样进行土工试验,进行三年的填土高程变化观测,并找出路基的沉降规律,以此验证室内研究成果。利用ANSYS程序分析预测结果和试验路观测结果对比分析,二者结果基本相符,程序预测与实测数据相比误差均在10%以内,可见运用该程序进行路基沉降分析符合工程实际。通过对高填方路基沉降各个影响因素的ANSYS模拟分析,对高填方路段减少路基沉降提出可行的技术操作措施。更多还原

【Abstract】 In recent years, with the process of highway extending in China, there will be more and more high fill subgrade. Because of the greatly different geological question met in the course of construction of highway in our country, the experience accumulated can’t be simply used in the country. One of the common faults is the deformation and damage of the high fill subgrade. The causes are very complex. It relates not only to the density of the filled soil for the roadbed,but also to the nature of roadbed filling materials, side-slope gradient, foundation nature, hydrology condition, roadbed pressing machine, design standard and construction method. In the projects, the deformation and damage of the high fill subgrade is mainly presented as cracks on the filled-soli for the embankment, sliding of the roadbed, collapse of the side slope and the related roadbed structure damage,whole or partial settlement of the roadbed etc. Once the high fill subgrade is deformed and damaged, it is very difficult to repair. Therefore, high attention must be paid to it. In order to avoid oversized settlement and deformation, further research on the settlement and deformation of high fill subgrade is much more meaningful.Therefore, to hig fill subgrade that Jilin province appeared, it is necessary to launch the observation on settlement and the research for settlement law of the high fill subgrade. By means of arranging and analyzing the measured data of the settlement of the high fill subgrade, the late settlement can be forecasted as well as the law of settlement and deform of the can be generalized, and for reasons given above, it can instruct further optimization design, improve relevant construction crafts, and offer directly scientific basis for decision of construction of the highway.Access to consult a large number of relevant information, this paper summary the history and present situation of the high fill subgrade settlement problems, review of the theoretical analysis of foundation settlement and common practical methods of calculating methods, discussed the problems and deficiencies of the high fill subgrade settlement mechanism and the traditional method. For these deficiencies, this paper analysis of high fill subgrade settlement mechanism based on the laboratory test results, and combined with finite element analysis software ANSYS, used for D-P geomaterials constitutive model. This paper analysis of high fill subgrade settlement problems, make plane strain elastic-plastic numerical simulation. Utilizing the flexibility of numerical simulation, in this paper, the effect of the factors including filling height, filling slope, filling material, the depth of foundation treatment, compaction of subgrade on the settlement are studied. Monitoring the variety of the height of filling of three typical test roads selected in Jilin province. Their settlements are recorded. The variety rule is studied. The results of the numerical simulation are verified by the monitor results. Comparing the results of ANSYS numerical simulation and monitoring of test road, it find that the both results are basically same. The errors are less than 10% between forecast settlements and real settlements. We can say that the forecast of the numerical simulation consistent with the real engineering. The measures that can be adopted to decrease settlements are proposed by simulation of various effect factors.更多还原