锈蚀RC梁承载力退化试验  

Experimental study of the degeneration of bearing capacity for corroded RC beams

作　　者：彭建新[1] 肖林发 唐皇[1] 张建仁[1] 

机构地区：[1]长沙理工大学土木与建筑学院,湖南长沙410004

出　　处：《长沙理工大学学报（自然科学版）》2014年第4期46-53,共8页Journal of Changsha University of Science and Technology:Natural Science

基　　金：国家"973"重点基础研究发展计划项目(2015CB057706);国家自然科学基金资助项目(51178060;51378081);交通部应用基础研究计划项目(2014319825160)

摘　　要：设计了12片3种不同保护层厚度的RC梁,在氯盐环境下对其进行通电加速腐蚀,进而对不同锈蚀程度的RC梁进行承载力试验。研究发现:1保护层厚度为25 mm的试验梁均呈现出了典型的脆性破坏,而保护层厚度较大的试验梁均有明显的屈服点,为延性破坏;2锈蚀率较大的试验梁侧面混凝土应变表现出很强的非线性,不再符合平截面假定;3试验梁有效截面尺寸及纵筋的锈蚀程度会随着保护层厚度的改变而发生变化,抗弯能力会随着纵筋锈蚀率的增大而逐渐减小,在两者的相互作用下试验梁出现了不同的破坏模式。最后,将理论极限承载力与试验结果对比分析,进一步讨论了锈蚀率对锈蚀RC梁承载力退化的影响规律。The accelerated current corrosive tests of 12 beams exposed to chloride corrosive environment are carried out among RC structures of three types of concrete cover depth. It is found that test beams with 25 mm concrete cover show a typical brittle failure, while structures of larger depth present obvious yield point and regarded as ductile fracture. The side concrete strain in the case of high corrosion rate appears strong nonlinearity and no longer accord with plane section assumption. Effective cross-sectional size of test beams and corrosion degree of longitudinal reinforcement change with concrete cover depth , and the bending capacity decreases gradually with the increase of longitudinal reinforcement corro- sion rate. As a result of interaction, test beams appear different failure modes. Finally, the- oretical ultimate bearing capacity being contrasted with the test results, further analysis of the influence of the corrosion rate on the bearing capacity of the tested beam have been studied.

关 键 词：锈蚀RC梁 保护层厚度 锈蚀率 承载力 

分 类 号：U448.34[建筑科学—桥梁与隧道工程]