商品混凝土强度波动的剖析

Analysis of Strength Fluctuation of Commercial Concrete

对 1 999年 5月至 2 0 0 0年 4月生产的上海地区常用商品混凝土 (强度等级为C2 0～C40 )的强度波动情况进行了剖析 ,结果表明 :混凝土 2 8d抗压强度月平均值夏季高于冬季 ,且随强度等级的降低而更加明显 ;混凝土强度随水泥强度的增高而增大 ;混凝土 2 8d抗压强度月平均值的标准偏差夏季低于冬季 。

The strength fluctuation of commercial concrete (C20～C40) produced by the Shanghai Jianguo & Jianhui Concrete Co., Ltd. during the period from May, 1999 to April, 2000 was analysed. The results show that the monthly average of 28 d compressive strength in summer is higher than that in winter, especially for low strength concrete. The standard deviation of the monthly average of 28 d compressive strength is lower for summer than that for winter. It means that the fluctuation of concrete strength in winter should be paid more attention.