Strength Development and Products Evolution of β-C2S and γ-C2S Induced by Accelerated Carbonation Curing  

作　　者：FANG Yanfeng LIU Zhichao WANG Qinghe ZHANG Yuzhuo ZHANG Miao WANG Qing FANG Yanfeng;LIU Zhichao;WANG Qinghe;ZHANG Yuzhuo;ZHANG Miao;王晴(School of Materials Science and Engineering,Shenyang Jianzhu University,Shenyang 110168,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;School of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China)

机构地区：[1]School of Materials Science and Engineering,Shenyang Jianzhu University,Shenyang 110168,China [2]School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China [3]School of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2020年第6期1053-1060,共8页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(Nos.51808354,51808351 and 51808532);the National Natural Science Foundation of Liaoning,China(No.20180550127);the China Postdoctoral Science Foundation(No.2018M641712);the State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology)。

摘　　要：Low calcium β-C2S and γ-C2S minerals with low hydration activity was activated by accelerated carbonation curing to be used as new binding materials.Synthetic β-C2S and γ-C2S were synthetized and compacted to prepare cube samples and then subjected to CO2 chamber for accelerated carbonation curing.The CO2 uptake,mechanical strength,and microstructure changes of β-C2S and γ-C2S were analyzed by TG,XRD,MAS-NMR,and MIP.The experimental results indicate the CO2 uptake of γ-C2S is much higher than that of β-C2S,but the compressive strength of γ-C2S samples is lower than that of β-C2S.Calcium carbonate and other carbonation products stack in the pore structure and the porosity is reduced from about 42% to 30.1% and 22.0% for β-C2S and γ-C2S samples after 2 h carbonation curing,respectively.The difference in compressive strength development is caused by the different properties of carbonation products.Except for calcium carbonate,there also exists obvious difference in properties of amorphous phases:γ-C2S formed silica gel in the whole carbonation progress;however,β-C2S can react to produce silica gel and C-S-H gel with high Van der Waals forces,and C-S-H gel will continue to react with CO2 to form calcium carbonate and silica gel in later carbonation reaction;In addition the microhardness of carbonated β-C2S was more higher than that of γ-C2S.

关 键 词：dicalcium silicate CARBONATION CO2 uptake HARDENING microstructure 

分 类 号：X701[环境科学与工程—环境工程] TQ172.1[化学工程—水泥工业]