负载锈蚀钢筋混凝土梁正截面抗弯承载力研究  

RESEARCH ON BENDING CAPACITY OF NORMAL SECTION OF CORRODED RC BEAM UNDER SUSTAINED LOADING

作　　者：徐港[1,2] 徐浩铭[1] 邓庆[1,2] 赵鹏[1,2] 

机构地区：[1]三峡大学土木与建筑学院,湖北宜昌443002 [2]三峡地区地质灾害与生态环境湖北省协同创新中心,湖北宜昌443002

出　　处：《工业建筑》2015年第12期83-87,109,共6页Industrial Construction

基　　金：国家自然科学基金资助项目(51109121;51379111)

摘　　要：采用自主设计的混凝土梁反力加载试验装置,对不同负载条件下锈蚀钢筋混凝土梁的抗力性能进行研究。在试验梁跨中设置保水槽并盛装3%的Na Cl溶液模拟海洋环境,采用恒电流加速锈蚀钢筋,试验工况分为不负载锈蚀、连续负载锈蚀、负载锈蚀卸载、负载不锈蚀及完好梁等5种,其中负载水平又按梁极限承载力的25%、45%和65%分为3种。研究表明:相同条件下,持荷状态对梁内钢筋的平均锈蚀率影响不明显,但负载水平对钢筋的锈蚀形态具有重要影响,随着负载水平的增加,钢筋的不均匀锈蚀程度渐趋显著;相同条件下,持续负载与否对锈蚀梁的承载力具有影响,较未负载锈蚀梁而言,负载锈蚀梁卸载后重新加载至破坏时两者极限承载力相近,但负载锈蚀不卸载梁的承载力更高;现有锈蚀梁正截面承载力计算模型具有一定的可靠性,然而尚不能充分揭示其退化机理。With the indigenously-designed loading device of RC beams,the resistance performance of corroded reinforced concrete beams under different load conditions was studied. A flume at midspan of the test beam full of 3%Na Cl solution was used to simulate the marine environment,and a constant current was used to accelerate the corrosion of the steel bars. The test conditions were divided into corroded without sustained loading,corroded with sustained loading, corroded with sustained loading and unloading, non-corroded with sustained loading and undamaged beam,the sustained loading levels of test beams were divided into 25%,45% and 65% ultimate bearing capacity. The research showed that under the same conditions,the influence of loading condition on the average corrosion ratio of rebar was not obvious,but loading level had greater influence on steel corrosion feature; with sustained loading or not had influence on bearing capacity of corroded beams,in terms of the load bearing capacity of corroded beams without sustained loading,the ultimate bearing capacity of corroded beam with sustained loading and unloading was close to corroded beams without sustained loading,but the load bearing capacity of corroded beams with sustained loading and unloading was higher,the existing normal section bearing capacity calculation model of corroded beams had a certain reliability,but could not fully reveal its degradation mechanism.

关 键 词：负载 锈蚀 钢筋混凝土梁 正截面抗弯承载力 

分 类 号：TU375.1[建筑科学—结构工程]