摘要
正确认识不同结构构造特征集料的碱硅酸反应 (ASR)特征 ,对判定集料碱活性和诊断工程ASR事例以及采取正确预防措施均有重要意义 .早期的以单一组分的高活性集料为基础提出的ASR模型只强调集料中活性组分对ASR的作用 ,仅适用于特定类型的高活性集料 .本工作用扫描电镜 (SEM )和光学显微镜研究了石英玻璃、沸石化珍珠岩和硅质砾石的ASR反应特征 ,并综合对慢膨胀型集料ASR研究的文献 ,提出了结构构造特征不同的硅质活性集料的ASR基本模型 :结构构造特征不同的活性集料其ASR过程及膨胀行为不同 ;对以无定型SiO2 为活性组分的均质高活性集料 ,反应特征符合传统的ASR模型 ;对致密、多矿物慢膨胀型集料 ,除活性组分类型和数量外 ,活性组分在集料内的分布 ,即集料的构造特征对ASR的速度和膨胀行为也有重要影响 .
In this work, the ASR features of silica glass, zeolitic perlite and siliceous gravel were examined by optical microscope and SEM. Based on the results and some published research on ASR of slow expansive aggregate, a hypothesis concerning ASR models for aggregates with different textures and structures was proposed. It suggests that (a) the ASR process and expansion behavior is different for aggregates with different textures and structures; (b) the classical ASR model is only suitable for interpreting ASR behavior of homogenous amorphous silica; and (c) for slow expansive poly_mineral aggregate, the distribution of the constituent or physical structure has strong influences on its ASR process and expansion behavior, in addition to the type and amount of reactive constituents in aggregates. The primary differences displayed in the ASR process and expansion behavior for aggregates with different textures and structures lie in the differences in the site and restrains condition for ASR expansion.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2002年第2期149-154,共6页
Journal of The Chinese Ceramic Society
基金
"九五"重点科技攻关项目 (96-5 3 5 -1-1)
关键词
混凝土
碱集料反应
碱硅酸反应
结构构造
模型
concrete
alkali aggregate reaction (AAR)
alkali silica reaction (ASR)
texture and structure
model
