桐子林水电站混凝土遇寒潮施工保温仿真研究

Simulative research on concrete insulation of Tongzilin Hydropower Station during construction period when encountering cold wave

早龄期混凝土遇寒潮时会产生较大内外温差,因寒潮历时短,混凝土表面温度梯度大,由此产生的温度应力也较大,如不采取保温措施,可能会产生表面裂缝。以桐子林水电站河床段(10号坝段)为研究对象,利用有限元方法,计算了在遭遇寒潮袭击时各种工况条件下混凝土的温度和应力,为选定施工期混凝土拆模后表面保温材料提供了依据。分析结果表明,选用2 cm厚的聚乙烯卷材时,可使混凝土浇筑块得到有效保护。

Large temperature difference in concrete mass would appears when encountering a cold wave and the temperature gradient is likely to be large due to the short duration of the cold wave. Therefore, the temperature stress tends to be large and it could induce surface cracks of concrete if no heat insulation measures are adopted. Taking the riverbed dam section of Tongzilin Hydropower Station as an example, we simulate the temperature and stress condition of concrete under various working conditions when encountering a cold wave by FEM method, providing reference for selection of surface heat insulation materials after removal of the concrete formwork. The results indicate that adopting polyethylene membrane with a thickness of 2cm can effectively protect the concrete blocks.