快速失水条件下纤维素醚改性水泥浆体水化规律  

Hydration Mechanism of Cellulose Ether Modified Cement Pastes Under Rapid Water-Loss

作　　者：马保国[1] 苏雷[1] 蹇守卫[1] 赵志广[1] 刘敏[1] 

机构地区：[1]武汉理工大学硅酸盐建筑材料国家重点实验室,武汉430070

出　　处：《土木建筑与环境工程》2013年第2期147-152,共6页Journal of Civil,Architectural & Environment Engineering

基　　金：国家自然科学基金(50902107);国家科技支撑计划(2011BAJ04B02);中央高校基本科研业务费专项资金(2011-YB-03)

摘　　要：以泡沫混凝土为高吸水性基体,研究了薄层纤维素醚改性水泥浆体在快速失水条件下的水化规律。从水泥浆体表面至与基体界面处,将水泥浆体平均分为3层,利用失水速度、含水率、XRD、FTIR和TG-DSC-DTG等测试方法对每层6h、12h、1d和3d的试样进行分析。结果表明:水化时间小于6h时,各层水泥浆体快速失水,只在第2和第3层中检测到Ca(OH)2的特征衍射峰。当水化时间大于12h时,失水速度显著降低,在3层水泥浆体中均可检测到Ca(OH)2的特征衍射峰,且从浆体表层至与基层界面处,水化产物衍射峰的强度不断增大,水化产物C-S-H凝胶中硅氧四面体的聚合态发生变化。随着水化时间延长,水化产物Ca(OH)2的衍射峰和振动峰不断增强。With foamed concrete as the absorbing substrate,under rapid water-loss,the hydration mechanism of cellulose ether modified thin layer cement pastes was studied.The cement pastes were divided into three layers from surface to interface.Each layer cement paste of 6 h,12 h,1 d and 3 d ages was analyzed by using water-loss speed,moisture content,XRD,FTIR and TG-DSC-DTG.The results show that cement pastes of different layers quickly lose water when hydration time is less than 6 hours and characteristic diffraction peaks of Ca（OH）2 are detected only in the second and third layer.The water-loss speed significantly decreases when hydration time is more than 12 h and characteristic diffraction peaks of Ca（OH）2 are detected in every layer.The content of Ca（OH）2 increases continuously from the first layer cement paste to the third layer cement paste and aggregation state of 4-in C-S-H gel changes.The intensity of diffraction and vibration peaks of Ca（OH）2 within cement pastes increases as hydration time prolongs.

关 键 词：纤维素醚 水泥浆体 失水速度 快速失水 泡沫混凝土 

分 类 号：TU528.01[建筑科学—建筑技术科学]