(1 清华大学土木水利学院，北京 100084； 2 山东科技大学土木建筑学院，青岛 266510； 3 大连理工大学土木水利学院，大连 116023)
［摘要］完成了对持续荷载作用下锈蚀梁、加载后卸载锈蚀梁、持续加载不锈蚀梁在使用阶段的对比试验。通过交替喷洒3.5%的盐水来模拟海洋潮汐环境，采用外加电流来加速钢筋锈蚀，整个试验过程中检测梁的锈蚀电流和跨中挠度。结果表明，荷载对钢筋锈蚀有明显影响，荷载作用使梁锈蚀加速，钢筋出现不均匀锈蚀。随着时间的增长，持续荷载作用下锈蚀梁的跨中挠度比没有锈蚀梁的挠度增长速度快。因此锈蚀钢筋混凝土结构在使用阶段的性能对耐久性能研究和使用寿命预测都非常重要。
［关键词］钢筋混凝土；锈蚀；持续荷载；挠度；裂缝
Effects of sustained loading on properties of corroded reinforced concrete beam during service in a simulated marine environment
He Shiqin1, Wang Haichao2, Gong Jinxin3(1 School of Civil Eng.,Tsinghua Uni.Beijing 100084,China; 2 School of Civil and Architectural Eng.,Shandong Uni. of Scienceand Tech.,Qingdao 266510,China; 3 School of Civil Eng. and Hydraulic,Dalian Uni. of Tech., Dalian 116023, China)
Abstract:Based on some results from the experiments which the beam specimens were subjected to fourpoint bending at various loading levels with sustained loading or previous loading while the steel bar corrosion, the other beams were subjected to sustained loading or without loading without corrosion of steel bars, the effects of loading on the properties of reinforced concrete beam in service were studied. The application of an external current and the 3.5% NaCl solution spraying was used to accelerate the corrosion of the reinforcement. Both the impressed corrosion current and the central deflections of the beams were recorded during the corrosion test process. The results show that the loading has a visible effect on corrosion. The corrosion of reinforcing steel is accelerated and un-uniform under simultaneous loading and accelerated corrosion conditions. The time-dependent deflection of the beams increases. The results suggest that for an investigation of the durability and service life prediction of reinforced concrete structures, the influence of the loading on the properties of corroded reinforced concrete structure in service stage should be considered.
Keywords:reinforced concrete; corrosion; sustained loading; deflection; cracking
山东省教育厅基金(J05N01)。
作者简介：何世钦，博士，Email:heshiqin@tsinghua.edu.cn。
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