【作者】 龚道勇；

【导师】 朱岳明；

【作者基本信息】 河海大学 ， 水工结构工程， 2002， 硕士

【摘要】 本文在总结前人研究成果的基础上，针对水利工程中的主要渗流问题，对稳定-非稳定、饱和-非饱和渗流理论和算法做了较详细的研究工作。主要内容包括： （1）从渗流基本理论出发，以压力水头为基本未知量推导多孔介质三维饱和-非饱和渗流微分方程，提出饱和及非饱和可能渗流逸出面边界条件严密合理的解决方法，特别是针对非饱和渗流逸出面的问题建立了二个有关定义，并编制相应的三维饱和-非饱和渗流程序，在此基础上分析了南京长江堤防某堤段水位变化时渗流场的变化情况。 （2）以饱和-非饱和渗流理论为基础，推导了考虑降雨入渗的三维饱和-非饱和渗流数学模型，初步解决了降雨入渗的数学建模问题，而且对于降雨入渗边界条件的合理处理也取得了成功，并对某矿区边坡典型的降雨过程和降雨入渗影响进行了客观的模拟。 （3）本文针对坝基密集排水孔的模拟问题，详细论述了基于固定网格结点虚流量法之上的改进排水子结构技术的算法理论及孔内边界条件的处理方法。 此外，本文基于碾压混凝土坝的渗流特点，在非均质各向异性等效连续体模型的基础上，提出了缝面无厚度平面单元模拟法。通过对江口坝基复杂渗控措施以及某碾压混凝土坝层面的精确模拟，事实证明利用改进排水子结构技术可以成功解决坝基密集型排水孔的模拟问题，缝面平面单元的提出基本上已较完美地解决了碾压混凝土坝的渗流建模问题。更多还原

【Abstract】 The author has particularly researched into the prominent problems of seepage in water conservancy engineering based on the steady-unsteady and saturated-unsaturated seepage theory and numerical method by summarizing the former achievement. The following is included:(1) Based on the fundamental seepage theory, the basic differential equation of saturated-unsaturated seepage in porous mediums has been deduced, in which the pressure head is the fundamental unknown quantity. The method for saturated-unsaturated possible spill boundary handling is presented. Particularly, two formulae are established for the problem of unsaturated spill boundary. The 3D saturated-unsaturated FEM program is developed by which changes processes of seepage fields with changes of water level in a certain section of Nanjing dike have been analyzed.(2) Based on the saturated-unsaturated seepage theory, the mathematic model under the condition of rain infiltration has been deduced. The problem of mathematic model is primarily solved and the rain infiltration boundaries have been successfully handled. Additionally, the typical rain processes and the influence of rain infiltration in a certain diggings are impersonally simulated.(3) Based on the method of nodal virtual flow rate of an unvaried finite mesh, the theoretic arithmetic for improving drainage substructure and the handling method of hole boundary conditions are discussed in order to solve the problem of drainage holes simulation.Furthermore, the aperture element model without thickness is present on the basis of the character of RCC dams and the symmetrical and anisotropic equivalental sequential model .The complicated seepage control measures of Jiangkou dam foundation. The result indicates that improving drainage structure may successfully deal with the problem of the simulation qf dense drainage holes and the problem of seepage model of RCC dams are fundamentally solved .更多还原