早期保湿养护时间和矿渣掺量对C40泵送混凝土抗碳化能力的影响  

Effect of moist-curing time at early ages and slag content on carbonation resistance of pumping concrete(C40 grade)

作　　者：叶青[1] 阮琦[1] 柴立英 

机构地区：[1]浙江工业大学建筑工程学院,浙江杭州310014 [2]杭州力澳商品混凝土有限公司,浙江杭州311112

出　　处：《新型建筑材料》2011年第11期7-11,共5页New Building Materials

基　　金：浙江省公益技术项目(2010C31117)

摘　　要：采用快速碳化试验对C40泵送混凝土抗碳化能力随早期保湿养护时间和矿渣掺量的变化规律进行了试验研究。结果表明，混凝土抗碳化能力随着早期保湿养护时间的减少和矿渣掺量的增加而明显降低。在早期保湿养护时间分别为28、7、3、2、1d再干养护到28d条件下，矿渣掺量为30％混凝土的28d快速碳化深度分别为8．2、10．5、16．1、20.3、25．8mm，由此可推算得到自然碳化（空气中CO2浓度以0．04％计）达到保护层厚度（25mm）所需时间分别为356．5、217．4、92．5、58．2、39．0a。因此，对于矿渣掺量达到30％-50％的混凝土，早期7d保湿养护是必要的。The variation of carbonation resistance of pumping concrete （C40 grade） with moist-curing time at early ages and slag content was studied by accelerated carbonation test in this paper. Results indicate that the carbonation resistance of the concrete decreased obviously with the moist-curing time at early ages reducing and the cement replacement by slag increasing. For example, in conditions of moist-curing regimes with 28,7,3,2 and 1 d moist-curing at early ages and dry curing for 28 days,the 28-day accelerated carbonation depths of the concrete incorporated with 30% slag were 8.2, 10.5,16.1,20.3 and 25.8 mm respectively,and thus it can be seen the calculated times when concrete cover（25 mm） was completely carbonated-naturally in the atmosphere with approximately 0.04% CO2 gas by volume of air were 356.5,217.4,92.5,58.2 and 39.0 years respectively. The results suggest that for the Carbonation resistance of the concrete incorporated with reaching 30%-50% slag the moist-curing time at early ages should need 7 days.

关 键 词：碳化 碳化系数 矿渣 早期保湿养护时间:泵送混凝土 

分 类 号：TU528.53[建筑科学—建筑技术科学]