【作者】 凌骐；

【导师】 黄淑萍；

【作者基本信息】 河海大学 ， 工程力学， 2006， 硕士

【摘要】 碾压混凝土坝是近年来被广泛采用的一种筑坝技术，随着建坝数量的增加和规模的日益庞大，带来的温度应力问题更加复杂，从而出现裂缝的可能也在增加。为了引导坝体中的温度裂缝在预定位置开裂，诱导缝作为一种结构措施在许多大型水电工程中都有所应用，并收到了良好的应力释放效果。关于诱导缝的作用机理和破坏准则已经有一些相关报道，但是在实际工程中如何结合模拟诱导缝的作用来分析坝体混凝土的温度场和温度应力场，国内外有关文献中都研究的较少。 本文首先阐述了碾压混凝土坝筑坝材料的热力学性能，并且对混凝土的重要特性之一——徐变——进行了研究，并给出了较为精确的拟合公式和计算程序。另外，文中也对大坝建成蓄水后形成的水库水温进行了详细讨论，通过建立一维的数学模型仿真求解了某水电站建成后的水库水温，为大坝运行期温度场和温度应力场的三维仿真分析给出了准确的边界条件。 本文重点以有限元法对某碾压混凝土拱坝的温度场和温度应力进行三维仿真分析，结合实际工程中设置的诱导缝数量和位置剖分网格，并考虑了不同的浇筑温度、冷却措施等施工条件，共进行了三个典型方案的计算。对计算结果分析后不仅对坝体温度场和温度应力场的分布情况有了明确的认识，而且对诱导缝在释放坝体局部高应力上的作用也进行了阐明。更多还原

【Abstract】 Roller-compacted concrete dam is a kind of widespread available construction technology in recent years. With the increasing of the quantity and scale of dams, there are such more sophisticated temperature-stress problems that the chances of appearing cracks are growing. For leading temperature-crack of dam concrete to split in the reserved positions, induced-crack was used in many large water-power engineering as a structure measure and gained well-known effectiveness in releasing stress. There are some coherent reports about mechanism of action and failure rules of induced-crack, but it is not enough how to analyze temperature field and temperature-stress field of concrete in dam body with simulating action of induced-crack in actual engineering in recent documents.In first, the paper sets forth thermal and mechanical performance of materials of RCC dam construction, and study one of important characters of concrete—creep—and gives out relatively exact fitting formula and calculation program. Otherwise, it is detailed discussed water temperature of reservoir after dam completed and impounded. The paper calculates water temperature of actual engineering by establishing linear dimension mathematic model and supplies exact terminal condition for three dimension simulating analysis of temperature field and temperature-stress field in operating period.The point of the paper is three dimension simulating analysis of temperature field and temperature-stress field of RCC arch dam by FEM. The paper divides meshes according quantity and position of induced-crack and takes in account of different construct conditions to calculate some typical schemes. After we analyzed the calculating results, we have clearly cognitions in distribution of temperature field and temperature-stress field. Furthermore, it illuminates action of induced-crack in releasing local high stress of dam body.更多还原