不同养护龄期矿物掺合料自密实混凝土碳化性能试验

Carbonation performance test of self-compacting concrete with different curing age mineral admixtures

设计了单掺粉煤灰、矿粉、石灰石粉、双掺粉煤灰矿粉、双掺粉煤灰石灰石粉5个系列的自密实混凝土试件,通过不同养护龄期的快速碳化试验研究不同矿物掺合料对自密实混凝土抗碳化性能的影响,并与普通混凝土抗碳化性能做对比。结果表明:养护龄期98 d左右,单掺矿粉的自密实混凝土抗碳化性能最好;养护龄期超过98 d的矿物掺合料自密实混凝土碳化深度逐渐增大;单掺石灰石粉自密实混凝土,其碳化深度值受养护龄期影响不大;矿物掺合料自密实混凝土等量取代水泥是有优势的。

Five series of self-compacting concrete specimens with fly ash,mineral powder,limestone powder,double fly ash ore powder and double fly ash limestone powder are designed.The effects of different mineral admixtures on the carbonation resistance of self-compacting concrete were studied by rapid carbonation tests of different curing ages,and compared with the anti-carbonization performance of ordinary concrete.The results show that the self-compacting concrete with single mineral powder has the best carbonation resistance when the curing age is about 98 d.Mineral admixtures with a curing age of more than 98 d gradually increase the carbonization depth of self-compacting concrete.The self-compacting concrete with limestone powder alone has little effect on the carbonation depth value due to the age of the curing;the mineral admixture is advantageous to replace the cement with the same amount of compacted concrete.