【摘 要】
：
By means of29Si and27Al magic angle spinning nuclear magnetic resonance (MAS NMR) combined with deconvolution technique, X-ray diffraction (XRD), scanning electron microscopy (SEM) as well as energy dispersive X-ray system(EDX), the effect of 5 wt% corros
【机 构】
：
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China;Col
【出 处】
：
武汉理工大学学报（材料科学版）（英文版）
论文部分内容阅读
By means of29Si and27Al magic angle spinning nuclear magnetic resonance (MAS NMR) combined with deconvolution technique, X-ray diffraction (XRD), scanning electron microscopy (SEM) as well as energy dispersive X-ray system(EDX), the effect of 5 wt% corrosive solutions (viz. 5 wt% Na2SO4, MgSO4, Na2SO4+NaCl and Na2SO4+NaCl+Na2CO3) on C-S-H microstructure in portland cement containing 30 wt%lfy ash was investigated.The results show that, in MgSO4 solution, Mg2+ promotes the decalciifcation of C-S-H by SO42-,increasing silicate tetrahedra polymerization and mean chain length (MCL) of C-S-H. However, the substituting degree of Al3+ for Si4+ (Al[4]/Si) in the paste does not change evidently. Effect of Na2SO4 solution on C-S-H is not signiifcantly inlfuenced by NaCl solution, while the MCL and Al[4]/Si of C-S-H in lfy ash-cement paste slightly change. However, the decalciifcation of C-S-H by SO42- and CO32- attack, as well as the activation of lfy ash by SO42- attack will increase the MCL and Al[4]/Si, which are both higher than that under Na2SO4 corrosion, MgSO4 or Na2SO4 +NaCl coordination corrosion.
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