【作者】 赵基花；

【导师】 李守义；

【作者基本信息】 西安理工大学 ， 水工结构工程， 2004， 硕士

【摘要】 碾压混凝土坝是分层浇筑的，这给大坝三维温度场和徐变应力场全过程仿真计算带来了巨大的计算工作量。为了降低仿真计算的规模，本文提出了以混凝土龄期为判断条件来控制网格浮动的三维有限元网格浮动计算模型，并从理论上分析论证了该模型的合理性，通过与固定网格法计算结果对比得出：该模型是可行的，并且在保证计算精度的前提下大大减小了工作量。 基于本文提出的计算模型，根据热传导理论、弹性徐变理论及有限元理论，作者编制了碾压混凝土溢流坝温度场及温度应力场的三维有限元仿真计算程序。该程序在编制过程中考虑了混凝土分层浇筑、施工间歇、弹模变化、绝热温升过程、环境温度的变化、混凝土徐变、自生体积变形等因素对坝体温度场及温度应力场的影响，同时也考虑了水管冷却、坝体表面保温、控制浇筑温度、施工汛期坝顶面过水等各种温控措施的数值模拟。 本文通过一典型算例对碾压混凝土溢流坝施工期和运行期温度场、徐变应力场进行了全过程仿真分析，较为系统的研究了碾压混凝土溢流坝施工期和运行期温度场、温度徐变应力场的分布规律。计算结果表明该程序是正确的，具有很大的实用性。 与该仿真计算程序配套的前后处理系统功能强大，界面友好，可视化程度高，方便实用，能在windows／98／2000／XP操作系统下运行。更多还原

【Abstract】 Owing to multi-lift characteristics of rolled concrete dams, great efforts of calculative work should be taken for computing 3-D temperature and stress fields of the dams. In order to reduce the calculation scale of the simulation, three dimension finite element relocating mesh model, which is controlled by the age of concrete, is presented. It’ s rationality is argued theoretically. Through the comparison by the fixed mesh method, it can be concluded that this model is effective, the precision can be assured and the amount of the calculation is reduced.Based on the relocating mesh model, according to heat conduction theory, elastic creep theory and finite element theory, simulation program for roller compacted concrete overflow dam is worked out through 3-D finite element method. In the program, the effect of lamination placement, construction interval, elastic modulus change, thermal insulation change, surrounding temperature change, concrete creep and autogenous volume change on thermal stress are considered. And such temperature control measurement as water pipe cooling, heat preservation of the dam surface, the pouring temperature control, the overflow across the dam top during flood season can also be simulated by numerical method.In this paper the temperature field and thermal-creep-stress field in roller compacted concrete overflow dam during construction and operation are simulated and the distribution law of them are systematically studied by an example. The results indicate that the program is correct and of greatutility.The before-treatment system and after-treatment system matched with this computing program are powerful and convenient because of its perfect interface. It can be operated in windows98/2000/XP.更多还原