摘要
粉煤灰能改善混凝土内部微观结构,对混凝土力学、热工及早期抗裂性能产生影响,本文通过改变粉煤灰的品质及掺量,Ⅰ级、Ⅱ级粉煤灰掺量分别设置0、10%、20%、30%、40%梯度试验组,对不同品质及掺量的粉煤灰型混凝土进行力学强度试验、平板热流计试验及早期抗裂试验,探究混凝土的抗压强度、保温蓄热性能及早期抗裂性能变化规律。结果表明:相同掺量下,高品质粉煤灰混凝土抗压强度有所提高,导热系数较高,保温性能有所降低,早期抗裂性能提升;相同品质粉煤灰掺量增加,混凝土抗压强度呈现先上升后下降趋势,其中粉煤灰10%掺量抗压强度提高效果较好,掺量超过30%抗压强度开始低于空白组;导热系数在粉煤灰掺量10%时较大,之后呈现下降趋势;混凝土早期抗裂性能随粉煤灰掺量的增加而提高,掺入一定量的粉煤灰对混凝土早期抗裂性能具有良好促进作用。
Fly ash can improve the internal microstructure of concrete, and has impact on the mechanics, thermal engineering and early crack resistance of concrete. In this paper, through changing the quality and content of fly ash, 0, 10%, 20%, 30% and 40% gradient test groups were set for grade I and II fly ash respectively, and mechanical strength test and plate heat flow meter test were carried out for different quality and quantity of fly ash concrete in order to explore the change rule of concrete compressive strength, heat preservation and heat storage performance and early crack resistance performance. The results showed that, under the same content, the compressive strength of high-quality fly ash concrete was improved, the thermal conductivity was higher, the thermal insulation performance was reduced, and the early crack resistance was improved;with the content increase of fly ash with the same quality, the compressive strength of concrete increased first and then decreased, and the compressive strength of 10% fly ash was better, and the compressive strength of concrete with more than 30% fly ash began to be lower. The thermal conductivity was larger when the fly ash content was 10%, and then it showed a downward trend;the early crack resistance of concrete increased with the increase of fly ash content, and the addition of a certain amount of fly ash had good promotion effect on the early crack resistance of concrete.
作者
郑大轩
李洁文
郭文彪
ZHENG Da-xuan;LI Jie-wen;GUO Wen-biao(Shenzhen Traffic Engineering Quality Supervision Station,Shenzhen 518000,China)
出处
《当代化工》
CAS
2021年第2期262-265,共4页
Contemporary Chemical Industry
基金
国家自然科学基金(项目编号:51908367)。
关键词
粉煤灰
抗压强度
导热系数
抗裂性能
Fly ash
Compressive strength
Thermal conductivity
Crack resistance
