摘要
开裂及自愈合是混凝土不可避免的现象。对3种不同水灰比的预制多裂缝试件,进行40 d和160 d在质量分数为6%的NaCl溶液中的完全浸泡试验,结果表明,裂缝面处出现了不同程度的自愈合,自愈合面积随水灰比减小而增大,随时间增长而逐渐增大,但增大的速度逐渐变小。相同深度处裂缝附近的自由氯离子质量分数随距裂缝距离的增大而减小,且由于自愈合减小了裂缝面处的有效面积,导致氯离子从裂缝面侵入的数量小于从暴露表面侵入的数量。
Cracking and self-healing are inevitable phenomenon for concrete structures.Three types of concrete specimens with multi-pre-cracks are designed for the test.Then the specimens were exposed to 6% NaCl solution for 40 d and 160 d.At last the self-healing area fraction in cracks＇ surface and chloride concentration in concrete near cracks were detected by RCT methods.Results show that self-healing area is increased with exposure time and the value of W/C,it decreases the crack surface and chloride ion in the crack,which makes the chloride ion ingress into concrete through crack surface be less than that through exposed surface.
出处
《工业建筑》
CSCD
北大核心
2011年第5期6-9,共4页
Industrial Construction
基金
国家自然科学基金重点项目(50538070)
国家"863"科技项目(2006AA04Z422)
国家自然科学基金项目(50809061)
关键词
混凝土
预制裂缝
氯离子
自愈
concrete
pre-crack
chloride ion
self-healing
