长期高温水热条件下活性粉末混凝土的水化规律  

Hydration of Reactive Powder Concrete Matrix under Long-Term Hydrothermal Condition

作　　者：赵秦仪 何兵 崔晓昱 侯剑桥 崔崇[1] 马海龙[3] ZHAO Qinyi;HE Bing;CUI Xiaoyu;HOU Jianqiao;CUI Chong;MA Hailong(Nanjing University of Science and Technology,Materials Science and Engineering,Nanjing 210094,China;Suzhou Concrete and Cement Products Research Institute Co.Ltd,Suzhou 215004,Jiangsu,China;Ningxia University National Preparatory School of Education,Yinchuan 750002,China)

机构地区：[1]南京理工大学材料科学与工程学院,南京210094 [2]苏州混凝土水泥制品研究院有限公司,江苏苏州215004 [3]宁夏大学民族预科教育学院,银川750002

出　　处：《硅酸盐学报》2020年第5期665-674,共10页Journal of The Chinese Ceramic Society

基　　金：国家自然基金项目(51772153,51468053)。

摘　　要：以0.21的水灰比成型活性粉末混凝土(RPC)基体,研究低水灰比RPC基体水化相在高温蒸压养护条件下的长期水化规律。采用酸不溶物含量表征基体的水化程度,采用显微维氏硬度表征RPC基体在养护过程中的结构性能,并通过X射线粉末衍射与扫描电子显微镜/能量色散谱分析RPC基体的物相与形貌变化。结果表明:高温蒸压养护过程中,RPC基体水化程度在0~96 h的养护期内快速提升,硬度随养护时间增加提升明显;长期养护时(168~312 h),基体的水化速率缓慢,基体内水泥熟料的水化趋于停滞。长期高温蒸压养护过程中,低水灰比RPC基体中晶态水化产物极少,由于缺乏晶态转化的空间,基体中的絮状水化硅酸钙凝胶无明显晶化现象,在长期高温水热条件下具有良好的稳定性,在核废料存储材料领域具有应用前景。A reactive powder concrete(RPC)matrix with a low water to cement ratio of 0.21 was prepared.The hydration of the RPC matrixes under long-term hydrothermal condition was investigated.The insoluble matter of the RPC matrix was examined to characterize its hydration level.The structural property of the RPC matrix was characterized using the Vickers hardness meter.The phase composition and morphology of the RPC matrix were characterized using X-ray powder diffraction and scanning electron microscopy/energy dispersive spectrometry.Under the hydrothermal condition,the hydration level of the RPC matrix increases during the autoclaved curing for 0-96 h,and the Vickers hardness of the RPC matrix also increases.The hydration rate of the RPC matrix is rather low,and the hydration of the clinker in the matrix becomes stopped during the long-term autoclaved curing(i.e.,168-312 h).In addition,there are a few crystalline hydrates in the RPC matrix cured for long-term,and the flocculent calcium silicate hydrates gel cannot be transferred to their crystalline forms due to the lack of space for the crystallization.The RPC matrix with a low water to cement ratio has a great stability under the long-term hydrothermal condition and a promising potential to be used as nuclear waste keeping materials.

关 键 词：低水灰比 活性粉末混凝土 长期水热条件 水化程度 水化硅酸钙凝胶 

分 类 号：TU-52[建筑科学]