Dehydration Characteristics of C-S-H with Ca/Si Ratio 1.0 Prepared Via Precipitation  

作　　者：何永佳 ZHENG Xiaohui 吕林女 YU Shumei DENG Gao HU Shuguang 

机构地区：[1]State Key Laboratory of Silicate Materials for Architectures(Wuhan University of Technology), Wuhan 430070, China [2]School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China [3]Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics (School of Science, Wuhan University of Technology), Wuhan 430070, China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2018年第3期619-624,共6页武汉理工大学学报（材料科学英文版）

基　　金：Funded by National Key R&D Program of China(No.2017YFB0310001);the National Natural Science Foundation of China(Nos.51772226,51272193,51072150)

摘　　要：Calcium silicate hydrate（C-S-H） with Ca/Si ratio 1.0 was prepared via precipitation in solution and heated at various temperatures to investigate its dehydration behavior. The dehydration, structural collapse and recrystallization characteristics of C-S-H and its microstructural change during heating process were investigated by XRD, SEM, Raman and TG-DSC techniques. C-S-H gradually lost non-evaporable water upon heating, about 50% and 80% non-evaporable water was removed below 200 and 400 ℃, respectively, and the rest was removed up to about 1 000 ℃. At 400 ℃, dehydrated C-S-H exhibited the increasing disordering of calcium/silicon environment and the decreasing symmetrical bending vibration of Si-O-Si of Q^2 silicate chains. At 650 ℃ non-bridging oxygen atoms（O（non）） attached to silicon were almost removed, and significant structural change occurred, and at 815 ℃ C-S-H dehydrated to wollastonite.Calcium silicate hydrate（C-S-H） with Ca/Si ratio 1.0 was prepared via precipitation in solution and heated at various temperatures to investigate its dehydration behavior. The dehydration, structural collapse and recrystallization characteristics of C-S-H and its microstructural change during heating process were investigated by XRD, SEM, Raman and TG-DSC techniques. C-S-H gradually lost non-evaporable water upon heating, about 50% and 80% non-evaporable water was removed below 200 and 400 ℃, respectively, and the rest was removed up to about 1 000 ℃. At 400 ℃, dehydrated C-S-H exhibited the increasing disordering of calcium/silicon environment and the decreasing symmetrical bending vibration of Si-O-Si of Q^2 silicate chains. At 650 ℃ non-bridging oxygen atoms（O（non）） attached to silicon were almost removed, and significant structural change occurred, and at 815 ℃ C-S-H dehydrated to wollastonite.

关 键 词：C-S-H heat dehydration structure morphology 

分 类 号：TU528[建筑科学—建筑技术科学]