联合活化多元辅助胶凝材料对蒸养混凝土性能的影响  

Effect of Combined Activation Multiple Supplementary Cementitious Material on Performance of Steamed Concrete

作　　者：佘亮 傅平丰[1] 邓威 陈雨齐 王显聪 SHE Liang;FU Pingfeng;DENG Wei;CHEN Yuqi;WANG Xiancong(College of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;Hebei Kehui Environmental Resources Co.,Ltd.,Xingtai 054100,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]河北科晖环境资源股份有限公司,邢台054100

出　　处：《硅酸盐通报》2022年第9期3059-3067,共9页Bulletin of the Chinese Ceramic Society

基　　金：国家重点研发计划(2018YFC1900604);中央高校基本科研业务费专项资金资助项目(FRF-MP-20-21)。

摘　　要：采用联合活化方法将粉煤灰微珠、粒化高炉矿渣、硅灰制备成高活性多元辅助胶凝材料,研究不同活化方式下,多元辅助胶凝材料对胶砂活性指数及水化产物的影响,探讨掺入多元辅助胶凝材料对混凝土抗压强度及抗硫酸盐侵蚀性能的影响,通过X射线衍射(XRD)、热重差热分析法(TG-DSC)和压汞法(MIP)对辅助胶凝材料水化产物及孔结构进行表征。结果表明:在静停6.0 h、90℃恒温4.5 h蒸汽养护(蒸养)后,联合活化后的多元辅助胶凝材料掺量为水泥质量的30%时,3 d、7 d和28 d胶砂活性指数分别为137.54%、140.06%和143.97%,浆体孔隙率为6.78%,胶砂流动度下降3.94%;当静停7.5 h、90℃恒温4.5 h蒸养后,与水泥组相比,混凝土1 d抗压强度提高了17.7%,且混凝土抗硫酸侵蚀系数提高5.8%;当静停6.0 h及90℃分别恒温4.5 h、7.0 h、12.5 h蒸养后,混凝土1 d抗压强度分别提高13.4%、16.2%和15.3%,7 d抗压强度分别提高16.3%、16.0%和15.2%。在联合活化作用下,辅助胶凝材料中高活性组分与水泥中Ca(OH)_(2)发生二次反应,促进水化硅酸钙(C-S-H)凝胶生成,优化了蒸养混凝土性能。Highly active supplementary cementitious materials(SCM)were prepared using fly ash microspheres,granulated blast furnace slag and silica ash via mechanical activation-chemical activation method.The effects of multiple SCM activated by different methods on activity index and hydration products of mortar were studied.The effect of multiple SCM addition on the compressive strength and sulfate corrosion resistance of steamed concrete was discussed.The hydration products and pore structure of materials were analyzed by X-ray diffraction(XRD),thermogravimetric method(TG-DSC)and mercury pressure method(MIP).The results show that by using multiple SCM to replace 30%(mass fraction)of cement,the 3 d,7 d and 28 d activity index of mortar reach 137.54%,140.06%and 143.97%after steam curing treatment with resting for 6.0 h and 90℃curing for 4.5 h,respectively.The porosity of the hardened paste is 6.78%,and the decrease ratio of mortar fluidity is 3.94%.When the resting time is 7.5 h and the steam curing time at 90℃is 4.5 h,the compressive strength of concrete for 1 d increases by 17.7%compared with cement group and the sulfate resistance coefficient of concrete increases by 5.8%.When the resting time is 6.0 h,and the steam curing time at 90℃is 4.5 h,7.0 h and 12.5 h,the compressive strength of concrete for 1 d increases by 13.4%,16.2%and 15.3%,and the compressive strength for 7 d increases by 16.3%,16.0%and 15.2%compared with cement group,respectively.The sulfate corrosion resistance coefficient of concrete reaches 90.1%.After the combined mechanical,chemical and hot steam high-temperature activation,the secondary reaction occurs between highly active components in SCM and Ca(OH)_(2) in cement,promoting the generation of calcium silicate hydrates(C-S-H)gel.Thus,it improves the performance of streamed concrete.

关 键 词：混凝土 辅助胶凝材料 联合活化 活性指数 孔隙率 流动度 抗压强度 抗硫酸盐侵蚀 

分 类 号：TU528[建筑科学—建筑技术科学]