【作者】 金生吉；

【导师】 熊健民； 余天庆；

【作者基本信息】 东北大学 ， 结构工程， 2009， 博士

【摘要】 随着我国西部开发的快速发展,建设向山岭纵丘方向不断深入,引起越来越多的公路稳定问题,为设计、施工和管理带来新的问题。十漫高速公路位于秦岭山脉南麓,跨越两郧断裂带,沿线存在多处滑坡、崩塌等地质灾害。本文结合山区高速公路特点,采用现场试验、监测、理论分析和数值模拟等方法,详细研究了山区超高填方多级挡土墙路基的沉降规律,山区超高填方多级挡土墙墙背土压力分布规律和山区超高填方多级挡土墙路基的稳定性。主要研究内容包括以下几个方面：1、在十漫高速公路深挖路堑边坡和高填路堤问题十分突出的5个标段上进行路基沉降试验、监测：在第四标段填方高度达67m的K32+670断面处,进行分层路基沉降测试试验。在第三标段填方高度为27.5m的K29+400～500处,采用剖面沉降仪对该高填方路基沉降进行测试试验。在三个典型路段K36+660-900、K47+500～600和K47+700～900,采用沉降桩进行路基沉降测试试验。通过对每个试验结果进行详细研究,发现了各个高填方路基的沉降规律,并深入分析了路基沉降机理。2、在建立高填方路基沉降预测模型的基础上,运用对数拟合法,Asaoca法,泊松曲线法和灰色模型预测法等方法,根据沉降试验的实测资料,对路基填筑的不同阶段及最终的沉降量进行预测,并对每种预测结果对比分析。3、通过在五级挡土墙墙背埋设土压力计测试墙背水平和竖直土压力,详细研究山区多级挡上墙墙背土压力分布规律,建立了山区多级挡土墙墙背水平土压力双直线计算公式。4、在五级挡土墙的第1、2第4级墙面上设置变形观测点,定期观测挡土墙墙面位移变化,通过深入研究,发现了多级挡土墙墙面变形、沉降和稳定性规律。5、对高填方路基应力应变和沉降变形进行数值模拟,运用ANSYS和Marc软件对十漫高速公路的两个高填方路基断面4K32+670断面和K31+625断面的应力应变和位移沉降进行了有限元数值分析。通过模拟分析发现了路基断面的拉应力最大值和沉降量最大等薄弱部位,这些模拟分析结果与现场原型观测的结果基本吻合。综上所述,本文研究建立了山区多级挡土墙墙背水平土压力双直线计算公式、山区多级挡土墙墙面变形预测模型和山区超高填方多级挡土墙路基(67m)的沉降预测模型,现场实践应用良好,取得的成果可为相类似山区高填方多级挡土墙路基的设计和施工提供了有益的参考和借鉴。更多还原

【Abstract】 With the rapid development of China’s western construction, building heads for the mountain and valley. At the same time, these increasing problems of road stability bring new challenges for the design, construction and management. ShiMan highway is the west part of YinChuan-WuHan highway in Hubei Province, located south of Qinling Mountain, straddling two YunXian fault zone. It is no easy to build for the existence of landslides, collapses and other geological disasters in the area.In this situation, the study of the settlement of fill subgrade and stability of retaining walls has been carried on.We have chiefly fulfilled the following tasks:First of all, the roadbed settlement experiments have been carried on in the five sections of ShiMan highway where high fill and deep slope geological disasters is very common and serrious:(1) Subgrade settlement observation experiment has been carried on at the cross-section of K32+670 on the 4th section of ShiMan highway with the highest fill of 76 meters. (2) By section-settlement-meter, Subgrade settlement experiment has been carried on at the cross-section of K29+400～500 on the 3rd section of ShiMan highway with the highest fill of 27.5 meters.(3) Subgrade settlement monitoring have been carried on by settlement-pile, at three sections of K36+660～900, K47+500～600 and K47+700～900 of ShiMan highway. Study on the settlement laws of the high fill embankment has been made by analyzing the experiment results and settlement mechanism has been analyzed as well.Secondly, prediction models on high-filling subgrade settlement have been proposed. The settlement rate at different stages and the ultimate settlement have been predicted by four methods:logarithmic fitting, Asaoca, poisson curve and gray prediction model, based on the measured data of the fill roadbed settlement. Results of each prediction method are compared and analyzed.Thirdly, the laws of earth pressure distribution against the back of multistage retaining wall has been studied by burying soil pressure gauge and monitoring level and vertical earth pressure on the back of retaining wall at 5 levels. The level earth pressure-time relation curve has been drawn. Thus, earth pressure formula suitable for multistage retaining wall at mountainous areas has been established.Fourthly, laws concerning deformation, sedimentation and stability of multi-level retaining wall has been got by regular observations of retaining wall displacement changes at deformation observation points of level 1,2 and 4,18.Finally, numerical simulation on stress, strain and settlement of high fill subgrade has been carried out. Stress-strain and displacement settlement of two high fill cross-section (4K32+670 and K31+625) of ShiMan highway have been studied by Ansys and Marc software. The largest tensile stress and weakest part of cross-section of the roadbed have been found through simulation analysis. Analysis results of these numerical simulations are approximately consistent with the results of the observations on the spot.In summary, the results provide scientific guidance for the design and construction of the roadbed. At the same time, the settlement theory of high-filling subgrade also can be referred to as a reference for construction of road, railway, mining, dam, embankment, and so on.更多还原