硫酸盐和氯盐侵蚀的混凝土梁抗弯性能  

The bending performance of concrete beams corroded by sulfate salt and chloride

作　　者：吴庆[1] 汪俊华[1] 耿欧[2] 陈小建[1] 

机构地区：[1]江苏科技大学土木工程与建筑学院,江苏镇江212003 [2]中国矿业大学力学与建筑工程学院,江苏徐州221116

出　　处：《中国矿业大学学报》2012年第6期923-929,共7页Journal of China University of Mining & Technology

基　　金：住房与城乡建设科学计划项目(2009-k2-3);国家自然科学基金青年基金项目(50808173)

摘　　要：为了研究混凝土结构在双重侵蚀环境中的退化规律,采用内掺5%NaCl浸泡于15%Na2SO4溶液中,湿2d、干3d的干湿循环加速腐蚀方法,研究了不同腐蚀损伤度和锈蚀率时试验梁的破坏形态、开裂情况、抗弯承载力的退化机理,并对不同腐蚀程度下试验梁的荷载-挠度曲线、挠度变形、腐蚀损伤度和锈蚀率对开裂荷载、极限荷载和延性的影响进行了分析.结果表明:早期侵蚀产物的生成密实了混凝土内部结构,随着腐蚀的加深,混凝土和钢筋的力学性能均下降,因此造成试验梁的开裂荷载、极限荷载、延性和截面刚度都经历了先增后降的过程,但是相对于开裂荷载,极限荷载的下降要晚些.根据试验结果建立了与腐蚀损伤度和锈蚀率相关的开裂荷载、极限荷载和延性比退化规律的计算模型.A dry-wet cycle, accelerated corrosion method was used to determine the degradation of reinforced concrete beams under a dual erosion environment. The test beams were soaked in 5o//oo NaC1 and 15% Na2SO4. Their shape, ductility, and bending capacity at different levels of corrosion were tested. The load-delfection, the beam deflection, and the cracking and ultimate loads and ductility were measured. At first corrosion makes the internal structure of the con- crete more dense but the mechanical properties of both concrete and reinforced concrete decline as the corrosion proceeds. This results in the load at fracture failure showing an initial increase followed by a decrease. The bearing capacity decreases after the drop in fracture failure load. Experimental results are used to predict the crack failure load, ultimate load, and ductility of beams having different amounts of corrosion.

关 键 词：腐蚀损伤度 锈蚀率 开裂荷载 极限荷载 延性比 截面刚度 

分 类 号：TU375[建筑科学—结构工程]