粉煤灰加气混凝土废砌块脱水相用作水泥混合材的试验研究

Study on dehydrated phases of fly ash aerated concrete waste block used as cement admixture

通过热分析及XRD分析,研究了不同温度处理的粉煤灰加气混凝土废砌块矿相变化,并测试了其作混合材对水泥力学性能的影响。试验结果表明,在600～800℃的煅烧温度范围内,粉煤灰加气混凝土废砌块物相转变经历了晶体→无定形→晶体的过程,综合考虑热分析、XRD分析及水泥强度发展,确定粉煤灰加气混凝土废砌块的适宜煅烧温度是700℃;原状粉煤灰加气混凝土废砌块掺量的增加会使水泥强度降低,700℃处理粉煤灰加气混凝土废砌块的适宜掺量为15%,此时水泥强度可达到P.C42.5水泥强度标准。

By means of thermal analysis and XRD analysis, the mineral phase changes of fly ash aerated concrete waste block that treated at various temperatures were studied. In addition, the effect of fly ash aerated concrete waste block used as cement admixture on physical properties of cement was also studied. The results indicated that the phases transformation process of fly ash aerated concrete waste block, at temperature range of 600-800℃, was crystal→amorphous→crystal. Based on the result of heat analysis, XRD analysis and developing of cement strength, it was determined that the appropriate calcination temperature of fly ash aerated concrete waste block was 700℃. The strength of cement would be decreased with increase of original fly ash aerated concrete waste block. The appropriate content of fly ash aerated concrete waste block, under the temperature of 700℃, was 15%. The strength of cement could satisfy the requirement of standard of P.C 42.5 cement.