基于生长单元网格浮动的碾压混凝土坝温度场分析

Procedure of element growing and mesh moving for simulation of 3-D temperature field of roller compacted concrete dams

针对碾压混凝土坝 (RCCD)成层施工和材料成层的结构特点 ,引入非均质层合单元和生长单元的概念 ,提出随着生长单元不断并层生长和网格的浮动 ,能仿真模拟RCCD的成层浇筑施工过程的算法 .同时 ,对某一高RCCD从施工期到运行期的温度场变化全过程进行计算分析 ,论证了入仓温度对大坝温度场的影响 ,探讨了该坝温度场的特性 ,为温控方案的确定提供了一定依据 .利用该算法 ,能达到坝体三维不稳定温度场计算的仿真 ,并可大大减少计算单元数 。

In consideration of the properties of multi laminated construction and multi laminated material structures, the concepts of inhomogeneous multi laminated element and growing element are introduced. On the basis of the concepts, a numerical procedure with a moving mesh is developed for simulation of the unsteady temperature field of roller compacted concrete dams. A numerical example is given, in which the whole process of temperature variation of a high RCC gravity dam is simulated with the procedure. The properties of the temperature field and the influences of the concrete pouring temperature on the temperature field of the dam are analyzed. To some extent, the computed results provide a basis for design of temperature control measures. Without decrease of the accuracy of computation, the new procedure with a moving mesh can largely reduce the computation scale and computation load.