掺加粉煤灰硬化混凝土中水泥含量的测定

为探讨测定掺加粉煤灰的硬化混凝土中水泥含量的方法,成型了不同粉煤灰掺量的混凝土试件,标准养护到不同龄期后,基于优化后的砂浆中水泥含量测定方法和硬化混凝土中砂浆含量测定方法,形成了测定掺加粉煤灰硬化混凝土中水泥含量的方法。采用该方法测定掺加粉煤灰的硬化混凝土中水泥含量结果显示:对于粉煤灰掺量不大于30%、龄期不超过90 d的混凝土,水泥含量的相对误差绝对值在14%以内;对于粉煤灰掺量不超过20%、龄期不超过360 d的混凝土,水泥含量的相对误差绝对值在18%以内;对于龄期相同的混凝土,水泥含量的相对误差随着粉煤灰掺量的增加而增大;混凝土中粉煤灰的活性成分在标准养护180 d以后对抗压强度的影响开始变得不明显。

Determination methods of cement content in hardened concretes w ith fly ash

In order to get the determination method that has the least error and the strongest adaptability of cement content in hardened concretes with fly ash,different samples with varied content of fly ash were prepared.After the concrete samples were cured for different ages in a standard environment,based on the improved determination method of cement content and the determination method of mortars content in hardened concretes.We found an ideal determination methods of cement content in hardened concretes with fly ash.By using this method,the relative deviation absolute value of cement content of hardened concretes with no more than 90 d ages and 30 percent fly ash content is set within 14%,and the hardened concretes with no more than 360 d ages and 20 percent fly ash content is set within 18%.The influence of the fly ash active components to the compressive strength begins to become insignificant after 180 days in a standard environment.