UHTCC对寒冷地区混凝土坝温度场的影响

PERMANENT FORMWORK OF ULTRA-HIGH TOUGHNESS CEMENTITIOUS COMPOSITES ON TEMPERATURE FIELD OF CONCRETE DAM

为解决混凝土坝越冬期因温度梯度脆性开裂问题,文中采用超高韧性水泥基复合材料永久保温模板,使用朱伯芳混凝土温度场简化算法及ABAQUS,计算表面裸露及外设永久保温板的混凝土坝温度分布情况。研究发现坝体表面采用75 cm厚超高韧性水泥基复合材料保温板时,坝体表面温度提高6.6℃;混凝土表面最低温度从-12.4℃,上升至7.1℃,保温效果优异。并对超高韧性水泥基复合材料保温板厚度进行参数分析,研究表明随着超高韧性水泥基复合材料保温板厚度增加,混凝土表面温度降幅进一步减小,混凝土表面得到有效保温。

An ultra-high toughness cementitious composites(UHTCC) permanent insulation formwork system is proposed to address the brittle cracking at concrete dams resulted from temperature gradient during winter season.The Zhu's simplified temperature field algorithm and ABAQUS are used to calculate the temperature distribution of concrete dams with exposed surfaces and permanent insulation formwork.The installation of a 75 cm thick UHTCC insulation formwork increases the surface temperature by 6.6℃;the lowest temperature on the concrete surface rises from-12.4℃ to 7.1℃,indicating excellent insulation performance.Furthermore,a parametric analysis is conducted on the thickness of the UHTCC insulation formwork.As the thickness increases,the temperature drop on the concrete surface further decreases,leading to effective thermal insulation.