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| Experimental study on mechanics behaviors of reinforced concrete beams under simultaneous chloride attacks and sustained load |
| JIN Wei-liang, WANG Yi |
| Institute of Structural Engineering, Zhejiang University, Hangzhou 310058, China |
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Abstract In order to hold up the joint effect of chloride attack and loads on the actual reinforced concrete structures, a loading device to be subjected to sustained load was designed and made to be used for the experiment of large-size reinforced concrete beams. Accelerated corrosion experimental way was conducted on reinforced concrete beams by the electro osmosis-constant current-wet and dry cycle (ECWD) under the joint action of chloride attack and sustained loading. The load-deflection curve, ductility and other flexural properties of the specimens were studied by loading test. By use of rapid chloride test (RCT) method, distribution of chloride ion concentration within the concrete protection layer of test beams was measured. The corrosion degree of longitudinal reinforced bars in tensional region was evaluated by the way of half-cell potential measurements and steel weighing method. The experimental results showed that with the increase of sustained load level, the chloride ion concentration within the concrete protection layer was higher, and the chloride ion might be accumulated around longitudinal bars in tensional region. Furthermore, the corrosion degree and its uneven extent of longitudinal bars were greater. Also the flexural properties of the specimens, which included yielding load, ultimate load, displacement ductility, were to some degree degenerated while the curvature ductility factor was bigger. Moreover the greater the loading level was, the higher the degradation level was.
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Published: 01 February 2014
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持续荷载与氯盐作用下钢筋混凝土梁力学性能试验
针对已有的研究以小尺度的试块实验而未能反映实际混凝土结构在荷载与氯盐耦合作用效应，自行设计大尺度钢筋混凝土梁的持续荷载施加装置，采用“电渗-恒电流-干湿循环”的方法对钢筋混凝土梁进行持续荷载作用下的加速锈蚀实验，并对试验后的混凝土梁的力学性能进行研究；同时，采用RCT方法研究试验梁混凝土保护层厚度范围内的氯离子分布规律，采用半电池电位法及称重法相结合来评价试验梁内纵向受拉钢筋锈蚀程度.结果表明:氯盐与持续荷载耦合作用下，随着持续荷载水平的提高，保护层厚度范围内的氯离子质量分数会增大，会在钢筋附近出现聚集现象；同时，也使纵向钢筋的锈蚀率增大，钢筋截面的锈蚀不均匀程度明显；导致混凝土梁的极限荷载减小，延性降低，截面曲率延性增高.
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| ［1］ 金伟良,袁迎曙,卫军,等.氯盐环境下混凝土结构耐久性理论与设计方法［M］.北京:科学出版社,2011.
［2］ 金伟良.腐蚀混凝土结构学［M］.北京:科学出版社, 2011.
［3］ PRITPAL S, MANGAT, MAHMOUD S, et al. Flexural strength of concrete beams with corroding reinforcement ［J］. ACI Structural Journal,1999,96( 1)： 149-158.
［4］ 金伟良,陈驹.海洋环境侵蚀作用下混凝土梁抗弯性能试验研究［J］.浙江大学学报：工学版.2004.38(5)： 603-609.
JIN Wei-liang, CHEN Ju. Experiment study on flexural capacity of reinforced concrete beams in marine environment ［J］. Journal of Zhejiang University: Engineering Science, 2004.38(5)： 603-609.
［5］ DIMITRI V. Val, Leonid Chernin2. Serviceability reliability of reinforced concrete beams with corroded reinforcement ［J］. Journal of Structural Engineering, 2009, 896905.
［6］ 施锦杰,孙伟. 弯曲荷载与氯盐耦合作用下混凝土中钢筋锈蚀程度评估［J］. 硅酸盐学报, 2010, 38(7): 1201-1208.
SHI Jie-wei, SUN Wei. Evaluation of steel corrosion in concrete under simultaneous flexural load and chloride attacks ［J］. Journal of the Chinese Ceramic Society. 2010, 38(7): 1201-1208.
［7］ DIAO Bo, SUN Yang, CHENG Shao-hong, et al. Effects of mixed corrosion, freeze-thaw cycles, and persistent loads on behavior of reinforced concrete Beams ［J］. Journal of Cold Regions Engineering, 2011,25(1): 37-52.
［8］ 延永东. 氯离子在损伤及开裂混凝土内的运输机理及作用效应［D］. 杭州：浙江大学,2011
YAN Yong-dong. Transportation of chloride ions in damaged and cracked concrete and its action ［D］. Hangzhou: Zhejiang University, 2011.
［9］ 舒正昌.荷载与氯盐共同作用下的混凝土耐久性试验研究［D］. 北京：北京工业大学, 2010.
SHU Zheng-chang. Research on durability of concrete structures under load and chloride ［D］. Beijing: Beijing University of Technology, 2010.
［10］ SCHNEIDER U, CHEN S W. The chemomechanical effect and the mechanochemical effect on high-performance concrete subjected to stress corrosion ［J］. Cement and Concrete Research, 1998, 28(4): 509-522.
［11］ 殷惠光,李雁.长期荷载及氯盐侵蚀协同作用下海沙混凝土梁耐久性试验研究［J］. 北京：建筑技术, 2011, 42(2): 159-162.
YIN Hui-guang, LI Yan. Experiment on durability of sea sand concrete beam under combined work of long-term chlorine salt corrosion and load ［J］. Architecture Technology, 2011, 42(2): 159-162.
［12］ 彭志.干湿循环与荷载耦合作用下氯离子侵蚀混凝土模型研究［D］.杭州:浙江大学, 2010.
PENG Zhi. Research on the mechanism of loading impact chloride penetration into concrete ［D］. Hangzhou: Zhejiang University, 2010.
［13］ 夏晋,金伟良.钢筋混凝土结构中非均匀锈蚀钢筋力学性能研究［J］.铁道科学与工程学报,2010,7(增刊): 69-73.
XIA Jin, JIN Wei-liang. Mechanical performance of the reinforcement with non-uniform corrosion in RC structures ［J］.Journal of Railway Science and Engineeing. 2010,7(Suppl): 6973.
［14］ CCES 01-2004.中国土木工程学会标准.混凝土结构耐久性设计与施工指南［S］.北京:中国建筑工业出版社, 2005.
CCES 01-2004. Guide to Durability Design and Construction of Concrete Structures ［S］. Beijing: China building industry press, 2005.
［15］ 李佩珍,谢慧才. RCT-快速氯离子检测方法及其应用［J］.混凝土. 2000,134（12）： 46-48.
LI Pei-zhen, XIE Hui-cai. RCT-The rapid chlorids test and its applications ［J］. Concrete, 2000: 134（12）： 46-48.
［16］ 彭啸宇,马洪超. 运用半电池电位法检测水工混凝土钢筋锈蚀技术简介［J］. 水利天地. 2006, 2: 42.
PENG Xiao-yu, MA Hong-chao. Test technology of reinforcement corrosion in reinforced concrete member by half-cell potential method ［J］. Hydroscience World, 2006, 2: 42-45.
［17］ 王慧芳. 钢筋砼梁截面延性的计算分析［J］.福建建筑,2000, 1: 30-31.
WANG Hui-fang. Calculation and analysis of ductility of section in reinforced concrete beams ［J］. Fujian Architecture＆ Construction, 2000, 1: 30-31. |
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