钢筋混凝土结构锈胀开裂及裂缝扩展试验研究  

Experimental study of corrosion-induced crack initiation and propagation of reinforced concrete structures

作　　者：王显利[1,2] 郑建军[3] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]北华大学交通建筑工程学院,吉林吉林132013 [3]浙江工业大学建筑工程学院,浙江杭州310014

出　　处：《大连理工大学学报》2009年第2期246-253,共8页Journal of Dalian University of Technology

基　　金：国家自然科学基金资助项目(50178003);吉林省科技发展计划资助项目(20080152)

摘　　要：采用加速腐蚀试验,系统地研究了钢筋直径、混凝土强度、腐蚀电流密度、保护层厚度、钢筋位置和类型等因素影响下钢筋混凝土锈胀开裂及裂缝扩展的规律.试验结果表明:腐蚀电流密度对锈胀开裂时间的影响最为显著,其他依次为钢筋直径、保护层厚度、混凝土强度;锈胀裂缝随时间增长呈线性增大趋势;各种因素对锈胀裂缝扩展的影响程度依次为腐蚀电流密度、保护层厚度、混凝土强度和钢筋直径;腐蚀电流密度越大、保护层厚度越小,锈胀裂缝扩展越快;混凝土强度等级越高、钢筋直径越小,锈胀裂缝扩展越缓慢.对比分析发现,钢筋位于上部和相同腐蚀电流下采用变形钢筋时,锈胀开裂晚且裂缝扩展更缓慢;钢筋位于角部时开裂早且裂缝扩展快.分析了各种因素影响机理并提出了提高耐久寿命的措施.An accelerated corrosion test was performed systematically to investigate the rules of time-to-cracking and crack propagating of RC affected by corrosion. The experimental variables studied include diameter of steel bar （d）, concrete strength （ft）, corrosion current density （icorr）, thickness of concrete cover （c）, sequence of the factors affecting t po he sition and types of steel bars, etc.. Test results show that the time-to-cracking is icorr, d, c and ft in turn; the corrosion crack width increases linearly with the time; the sequence of the factors affecting the crack width propagating is icorr, c, ft and d in turn. Moreover, the rate of crack propagating increases as icorr and d increase. While it decreases with the increasi deformed bar increases more slowly than that current density. When plain bar is that of the contrasted specimens. ups And ng of of c and ft. The crack width of the case of the the specimen of plain bar with the same corrosion ide of the specimens, the crack propagation rate is slower than when plain bar is at the corner of the specimens, it is faster than that of the contrasted ones. Based on the analyzed experimental results, measures to improve service life of RC are derived.

关 键 词：钢筋混凝土 腐蚀 裂缝 耐久寿命 

分 类 号：TU375.5[建筑科学—结构工程]