水闸闸墩施工期温度场和应力场的仿真计算分析

结构的内外温差、基础温差是混凝土结构施工期易开裂的主要原因，为此，结合混凝土温度场、应力场的基本原理和水管冷却的精确算法，通过三维有限单元法对施工期某水闸闸墩进行仿真计算，分析闸墩混凝土施工期温度场、应力场的时空变化规律，得出在温降阶段闸墩门槽处是裂缝容易出现的地方．计算结果表明，表面保温和内部水管降温相结合的温控措施既能减小结构的内外温差又能降低结构的基础温差，具有良好的防裂效果，且模板外面贴保温板的保温方法能使混凝土表面的施工质量得到明显改观，值得应用推广．

Simulation and Analysis of Temperature Field and Stress Field of Sluice Pier Concrete During Construction

In view of the problem of concrete cracks in construction period, the internal and external temperature difference and the basic temperature difference are considered as the main factors inducing the phenomena. Under the basic theories of temperature field and stress field of concrete, the 3-D FEM with the numerical algorithm of pipe cooling was adopted to simulate the temperature field and stresses field of sluice pier during construction. Through analyzing the time-space variation law, it can be found that cracks usually appear at gate slots in the stage of temperature drop. The results also show that the combination method of external heat preservation and internal cooling water pipes can decrease the temperature difference at early age and the basic temperature difference in later stage. Feedback information from fieldwork indicates that good effect of temperature control and crack prevention has been achieved. At the same time, the method of external insulation board also makes the quality of surface concrete obviously improved, so it deserves to be popularized.