【作者】 耿敏；

【导师】 窦远明；

【作者基本信息】 河北工业大学 ， 结构工程， 2013， 博士

【摘要】 高填方路堤具有填方高度大、占地面积宽、填方量大的工程特点，土工格栅以其强度高、柔性好的特点被广泛应用于路堤加固工程中，在高填方路堤中铺设土工格栅，通过路堤填料与土工格栅之间具有良好的摩擦效应，不仅可以限制土体的沉降变形，还能提高土体的强度和稳定性。然而，现有的加筋土理论研究并不完善，加筋机理和设计理论的研究仍落后于工程实践，加之山区地质条件复杂，工程竣工后，随着时间的增长以及车辆荷载的重复作用，高填方路堤容易出现局部沉降变形、整体下沉以及边坡失稳等问题，因此对加筋高填方路堤变形与稳定性的研究具有重要意义。本文以河北省某高速公路高填方路堤工程为背景，采用理论分析与实际观测相结合的方法展开讨论，通过室内拉拔试验、现场沉降观测、数值理论研究与FLAC3D数值模拟等方法，系统研究了土工格栅加筋高填方路堤的加筋机理、高填方路堤沉降变形的预测方法及预防措施、边坡稳定性分析方法等问题，主要研究工作如下：1、运用正交试验设计原理，对影响室内拉拔试验的各因素进行研究，得到影响因素的主次顺序及其变化规律。2、根据现场实测数据，分析了高填方路堤的沉降变形规律、沉降变形特征以及沉降变形机理，提出了预防高填方路堤沉降变形的措施。3、基于灰色系统理论和BP神经网络预测模型的特点，根据位移分解原理，提出了一种新型的灰色-BP神经网络预测模型，通过与实测数据进行对比，证明了预测模型的可行性。4、利用FLAC3D有限差分软件，对高填方路堤工程进行了数值模拟分析，研究了高填方路堤在加筋和未加筋情况下的沉降变形及稳定性情况，并探讨了加筋土的计算分析方法。5、利用公式推导了高填方路堤最佳加筋位置，并对瑞典条分法、简化Bishop法、Janbu法三种稳定性计算方法进行了分析，研究了不同因素对加筋高填方路堤变形与稳定性的影响。更多还原

【Abstract】 A high embankment is a form of road with great filling-height, wider taking-up and large filling quantities. Geogrid with the properties of strong tensility and low extensibility is widely used in embankment reinforcement project. The strong friction between the filling and geogrids in it can restrict the deformation of soil, and can improve the strength and stability of soil. However, the existing reinforced soil theory is not perfect and reinforced mechanism and the design theory still lags behind practice. Combined with complex geological conditions in mountainous area and the repeated loading of the vehicle after the project, high embankment easily appears issues of local and global settlement deformations or slope instability. Therefore, the study on deformation and stability of geogrid reinforced high embankment is of great practical significance.Based on geogrid reinforced high embankment project of Hebei province, using indoor pull-out test, and settlement observation during the project, and numerical analysis, and FLAC3D numerical simulation method, we take theoretical analysis and actual observation to make discussion and study the reinforced mechanism of geogrid reinforced high embankment, and the predict method and the preventive measures for the deformation and settlement of the high embankment and slope stability analysis method and so on. The main works are as follows:1. Based on orthogonal test design principles, we study the influence factors of interface friction characteristics of reinforced soil and obtain primary and secondary order of the influence factors and variation of each factor.2. In this paper, we study deformation rules, deformation characteristics and deformation mechanism of high embankment according to settlement data of field measurement, and propose some measures to prevent settlement and deformation of high embankment.3. Based on gray system theory and BP neural network prediction model, we put forword a new predict model by using displacement trends of embankment deformation, this new model can predict settlement after construction and is feasible through comparing with field observation data. 4. In this paper, we study deformation and stability of reinforced embankment and no reinforced embankment and calculation method of reinforced embankment by using the FLAC3D coding and analyszing calculation algorithm of reinforced theory.5. In this paper, we deduce the best reinforced position and analyzed three calculation methods, such as Sweden Slice Method, and Simplify Bishop Method and Janbu Method, and study the different influence factors of deformation and stability of reinforced high embankment.更多还原