摘要
从多尺度综合研究了纳米SiO_2对混凝土界面过渡区早期力学性能的影响.在宏观尺度上,主要测试了纳米改性混凝土的弹性模量及抗压、抗折强度,在微观尺度上,采用纳米压痕对其界面过渡区进行了压痕模量及其频数分布分析.结果表明:掺入纳米SiO_2后,无论水泥石还是混凝土,其早期强度及弹性模量均有所提高,且混凝土强度的提高尤为明显;纳米改性混凝土界面区的孔隙和缺陷显著减少,且形成了更高密度的C-S-H凝胶相,使其压痕模量与水泥石的压痕模量接近.
The effect of nano-SiO2 on the early mechanical properties of interracial transition zone in concrete was studied at multi-scale levels. At macrolevel, the static modulus of elasticity, compressive and flexural strength were measured; at microlevel, the values and distribution of indentation modulus in inter- facial transition zone were analyzed by nano-indentation. Results show that the addition of nano-SiO2 improves the early strength and modulus of both cement paste and concrete, in particular, a much significant increase of strength for concrete was observed. The amount of micro-pores and defects decreases remark- ably and C-S-H gel with higher density forms in ITZ of concrete modified by nano-SiO2, thus the indentation modulus of ITZ is much closer to that of bulk paste.
作者
徐晶
王彬彬
赵思晨
XU J ing WANG Binbin ZHAO Sichen(Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Tongii University, Shanghai 201804, China)
出处
《建筑材料学报》
EI
CAS
CSCD
北大核心
2017年第1期7-11,共5页
Journal of Building Materials
基金
国家自然科学基金资助项目(51378011)
关键词
界面过渡区
纳米SIO2
纳米压痕
弹性模量
interfacial transition zone（ITZ）
nano-SiO2
nano-indentation
elastic modulus
