（1 上海市工程结构新技术重点实验室， 上海 200032； 2 上海市建筑科学研究院（集团）有限公司， 上海 200032）

［摘要］分析了混凝土在高温下和高温后两阶段中性化过程的机理，并通过试验研究了经历两阶段中性化过程后中性化深度的变化规律。研究结果表明：混凝土在高温下和高温后两阶段中性化过程中的中性化机理不同，前者对后者有一定影响；经历两阶段中性化过程后，随混凝土强度增加中性化深度减小幅度不断降低；随温度升高，中性化深度不断提高，但经历800℃高温后混凝土再碱化程度较高，对混凝土碳化具有一定的抵抗作用；高温后混凝土微观结构变化明显，能够反映出混凝土的中性化特征。

［关键词］高温; 混凝土; 中性化深度; 微观结构

中图分类号：TU528.01       文献标识码：A       文章编号：1002-848X(2014)09-0072-03

Experimental research on neutralization mechanisms of concrete suffered from high temperature

Gao Rundong1,2, Li Xiangmin1,2, Xu Qingfeng1,2, Wang Qiong2, Yu Linfeng2

 (1 Shanghai Key Laboratory of New Technology Research on Engineering Structure, Shanghai 200032, China; 2 Shanghai Research Institute of Building Sciences (Group), Co., Ltd., Shanghai 200032, China)

Abstract: Neutralization mechanisms on the two-stage neutralization process at high temperature and after high temperature were analyzed, and neutralization depth change regularities after the two-stage neutralization process were tested. Study results indicated: concrete neutralization mechanism at high temperature was different from that after high temperature, and the former had some effect on the latter. After the two-stage neutralization process, with concrete strength increased, the reduced amplitude of the neutralization depth was decreased. With the temperature elevated, the neutralization depth was increased, but concrete realkalisation after 800℃ could be enhanced, which would resist the carbonation to some extent. The micro-structure of concrete had obvious change after high temperature, by which the concrete neutralization features could be reflected.

Keywords: high temperature; concrete; neutralization depth; micro-structure

*上海市科委应用技术开发项目（2011-114），上海市人才发展资金资助项目（2011058）,上海市自然科学基金资助项目（12ZR1426800）。

作者简介：高润东，博士，高级工程师，Email: grdong_1@163.com。

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