高原地区混凝土徐变性能控制研究

Performance Controlling Study on Creep of Concrete in Plateau Area

混凝土的徐变容易导致大跨径连续刚构桥的长期变形,而高原地区较低的湿度会加剧混凝土的徐变,影响混凝土结构的性能。本文结合高原地区的环境特点,考察大气温湿度对于混凝土徐变的影响规律,从混凝土配合比参数、加载龄期以及早期养护方式的选择等角度进行了研究分析。结果表明,减小水胶比、掺入粉煤灰、减小砂率、延长加载龄期、保证早期养护湿度能够有效控制混凝土的徐变,提升混凝土结构的质量。

Creep of concrete can result in long-term deflection of the long-span continuous rigid frame bridge. Low humidity in plateau area will intensify the creep of concrete and affects the performance of concrete structure. This paper inspects the influence of air temperature and humidity, then the mix parameters, loading age and early-age curing mode to creep law of concrete are studied and analyzed. The results show that reducing the water-cement ratio, mixing fly ash, reducing the rate of sand, extending the age of loading and ensuring early curing humidity can control the creep of con- crete effectively and enhance the quality of concrete structure.