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(1 清華大學(xué)土木水利學(xué)院，北京 100084； 2 山東科技大學(xué)土木建筑學(xué)院，青島 266510； 3 大連理工大學(xué)土木水利學(xué)院，大連 116023)
［摘要］完成了對持續(xù)荷載作用下銹蝕梁、加載后卸載銹蝕梁、持續(xù)加載不銹蝕梁在使用階段的對比試驗(yàn)。通過交替噴灑3.5%的鹽水來模擬海洋潮汐環(huán)境，采用外加電流來加速鋼筋銹蝕，整個(gè)試驗(yàn)過程中檢測梁的銹蝕電流和跨中撓度。結(jié)果表明，荷載對鋼筋銹蝕有明顯影響，荷載作用使梁銹蝕加速，鋼筋出現(xiàn)不均勻銹蝕。隨著時(shí)間的增長，持續(xù)荷載作用下銹蝕梁的跨中撓度比沒有銹蝕梁的撓度增長速度快。因此銹蝕鋼筋混凝土結(jié)構(gòu)在使用階段的性能對耐久性能研究和使用壽命預(yù)測都非常重要。
［關(guān)鍵詞］鋼筋混凝土；銹蝕；持續(xù)荷載；撓度；裂縫
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
山東省教育廳基金(J05N01)。
作者簡介：何世欽，博士，Email:heshiqin@tsinghua.edu.cn。
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