【作者】 高鑫；

【导师】 杜丽惠；

【作者基本信息】 清华大学 ， 水利工程， 2010， 硕士

【摘要】 混凝土面板堆石坝是堆石坝中的一种坝型,它以堆石体作为坝体的主体支撑结构,以坝体上游设置的混凝土面板作为主要防渗结构。它具有施工造价省、施工工期短、施工简便、对地形适应性强等特点,因此发展速度很快,已经成为当今世界部分国家和地区特别是我国坝工设计的主要坝型之一。在混凝土面板堆石坝的应力变形有限元数值分析中,作为坝体的主要组成部分,堆石体的应力变形分析显得尤为重要。堆石体本构模型是堆石体应力变形分析的基础,选择合适的堆石体本构模型是进行混凝土面板堆石坝的应力变形有限元分析的重要前提之一。在学习和分析了邓肯-张的E-B模型和清华大学非线性K-G模型之后,本论文提出了K-ν模型。它是以体积模量K与切线泊松比νt为主要参数建立的本构模型。相比邓肯-张的E-B模型及其前身E-ν模型,K-ν模型引入了切线泊松比的计算思路,但是对其计算方法进行了优化;相比清华非线性K-G模型,K-ν模型沿用了其土体临胀强度和体积模量的计算方法,但是去掉了需要采用等应力比实验才能准确确定的剪切模量G,而代之以切线泊松比νt;通过体积模量K与切线泊松比νt建立了增量加载的弹性矩阵关系。但是由于实验数据所限,本论文并没有完成卸载情况下的切线泊松比计算方法以及加卸载条件的判定。因此本论文提出的K-ν模型并不完整,有待进一步的研究。应用MSC.Marc软件二次开发平台的本构模型开发接口,完成了K-ν模型的程序开发,并使用一个简单的有限元模型对程序进行了验证。结果表明,K-ν模型能适应混凝土面板堆石坝的有限元计算。应用K-ν模型对清江水布垭混凝土面板堆石坝和堵河潘口混凝土面板堆石坝进行了三维应力变形有限元分析,并与清华非线性K-G模型的分析结果进行了对比和分析。特别是将K-ν模型的计算结果与水布垭面板堆石坝实测变形数据进行了对比分析。分析结果表明,K-ν模型的计算结果与实测变形数据较吻合,特别是次堆石区的计算结果与实测数据十分接近。以上结果表明,K-ν模型能较好地应用于实际工程的应力变形有限元分析。更多还原

【Abstract】 Concrete face rockfill dam(CFRD) is one type of rockfill dam, its main supporting structure of dam body is the rockfill structure, and its main impermeable structure is the concrete panel set at the upstream side of the rockfill structure. It has many advantages such as lower construction cost, shorter construction period, more simple construction method, and higher adaptability to the terrain features. In recent years, CFRD has developed quickly and became widely used in many parts of the world, especially in china.In the stress and deformation numerical analysis with finite element method(FEM) of CFRD, as the main component of the dam, the stress and deformation numerical analysis of rockfill is particularly important. The constitutive model is the base of numerical analysis of stress and deformation, so it is particularly important to select an appropriate constitutive model of rockfill to support the stress and deformation numerical analysis of CFRD.After studying and analysing Duncan-Chang E-B model and Tsinghua university nonlinear K-G model, this paper puts forward the K-νmodel. It is established with volume modulus and tangent poisson’s ratio. Compared with Duncan-Chang E-B model and its former form, the E-νmodel, K-νmodel introduced and optimized Duncan’s compute method of tangent poisson’s ratio; Compared with Tsinghua university nonlinear K-G model, K-νmodel introduced the compute method of strength criterion and volume modulus, but cut off the shear modulus who can determine exactly only by constant ratio of principal stress path experiment, and established the stiffness matrix by this volume modulus and tangent poisson’s ratio. But limited by the experiment data, this paper didn’t finish the compute method of tangent poisson’s ratio when unloading and the loading-unloading conditions judgment. So now K-νmodel is just an unfinished constitutive model and need more research.K-νmodel program was developed with the interface of constitutive model of the MSC. Marc software development platform, and validated by the analysis of Shuibuya CFRD 2D model. Results show that K-νmodel can adapt to the FEM analysis of CFRD.Stress and deformation with FEM analysis using K-νmodel of Shuibuya CFRD and Pankou CFRD 3D model were finished. Compute results show that K-νmodel can adapt to real project analysis.更多还原