超长大体积混凝土箱型基础无缝施工的分块跳仓浇筑技术

Block-divided Pouring for the Seamlessness of Bulky Concrete Box Foundation

工程结构中的大体积混凝土箱形基础,施工期间混凝土水化热引起的温度作用和自身收缩等变形将产生较大的温度应力,若设计和施工不当就会产生危害性裂缝。过去,我国大多采用设置伸缩缝或后浇带的方法来解决这种问题,但由于结构的整体性、使用功能和建设工期等方面的原因,现对这类结构均提出了无缝施工的要求。文章对超长大体积混凝土箱型基础的混凝土裂缝机理和应力计算方法进行分析研究,选择与之受力接近的计算模型,进行无缝施工分块跳仓间距的计算分析,从理论上证实超长大体积混凝土箱型基础无缝施工的可行性,并指出了施工中应注意的事项。

Due to the temperature stress produced by hydration heat and the shrinkage of the concrete proper, the bulky concrete box foundation is liable to hazardous crack under inadequate design and construction. The above-mentioned problem was formerly solved by setting expansion joint or embedded joint in our country. But the structural integrity, function and limit construction period has required seamlessness from the construction of bulky concrete box foundation. The article makes analytical study on the crack mechanism and stress calculating methods and carries out computational analysis of the space between dividedly-poured blocks based on a computational model under similar stress with the original bulky concrete structure. It has theoretically proved feasible for the seamless construction of bulky concrete box foundation with block--divided pouring and finally brought forth the possible elements during the concrete construction.