墩墙混凝土结构施工期温控防裂

Temperature control and crack prevention of thin-walled concrete structures during construction

针对施工期墩墙混凝土结构易开裂的问题,阐述了裂缝成因和开裂机理,提出了相应的防止措施。认为墩墙混凝土结构早期的内外温差,后期基础温差是这类裂缝产生的主要原因,而表面保温和内部水管降温的温控防裂措施是防止这类裂缝的有效措施。通过三维有限单元法对某大闸施工期混凝土在该温控防裂措施下温度场和应力场的仿真计算,结果显示该防裂措施效果良好,对类似工程具有一定的参考价值。

In view of the problem of concrete crack in the period of construction, this paper lntroauces me forming mechanism of crack in thin-walled concrete structure and puts forward the corresponding measures and methods. Generally speaking, the temperature difference between the inside and outside at early stage and the basic difference of the temperature at later stage are considered as the main factors influencing the phenomena, while the external heat preservation and internal cooling pipes measures achieve better effect on preventing cracks. The 3-D FEM is adopted to simulate the thermal field and stresses field of concrete constructed subsequently and the result shows that good effect of temperature control and crack prevention is achieved. This should have great reference signification to similar concrete projects in the future.