碳化再生复合微粉对碱矿渣材料的影响

Effiect of carbonated recycled composite powder on alkali slag materials

利用CO_(2)处理再生微粉与再生砖粉的复合微粉替代矿渣制备碱矿渣(AAS)砂浆,探究了碳化再生复合微粉(CCP)替代水平对AAS砂浆凝结时间、力学强度和吸水率的性能影响。结果表明:当CCP替代率为10%时,抗压强度获得最优值,高出未处理的再生复合微粉(RCP)19%;CCP主要成分为CaCO_(3),在碱性环境下溶解性较低,可抑制AAS净浆的凝结时间的发展;相较于RCP,CCP的加入会进一步加大AAS砂浆的吸水率。此外,CCP在AAS砂浆中具有较好的生态和经济效益。

This study investigated the utilization of CO_2-treated recycled concrete powder and recycled brick powder composite as a substitute for slag in the alkali-activated slag(AAS)mortar.The impacts of varying substitution levels of carbonated recycled composite powder(CCP)on the setting time,mechanical strength,and water absorption characteristics of AAS mortar were investigated.The results reveal that a 10% substitution rate of CCP yields the optimal compressive strength,surpassing that of untreated RBP by 19%.The main component of CCP is CaCO_3,which has low solubility in alkaline environments andconsequently retards the setting time of AAS paste.Compared to RCP,the incorporation of CCP results in a further increase in the water absorption rate of AAS mortar.Furthermore,CCP has better ecological and economic benefits in AAS mortar.