锈蚀钢筋再生混凝土梁试验研究及刚度分析*
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(1 南京航天航空大学， 南京 210016； 2 内蒙古科技大学， 包头 014010；3 上海宝冶工程技术有限公司房屋质量检测站，上海 200941；4 包头市中冶置业有限责任公司， 包头 014010； 5 中国二冶集团有限公司， 包头 014010)［摘要］通过12根不同钢筋锈蚀率下粗骨料取代率为100%再生混凝土梁的静荷载试验，分析钢筋锈蚀率对再生混凝土梁的破坏形态、裂缝发展规律、荷载-挠度曲线、平截面假定的影响。结果表明：当钢筋锈蚀率小于10%时，梁由于材料强度遭到破坏而发生弯曲延性破坏；当钢筋锈蚀率大于10%时，梁由于钢筋与再生混凝土的粘结失效而发生粘结-剪切脆性破坏；随着钢筋锈蚀率的增加，钢筋与再生混凝土之间的粘结性能先增加后降低，但再生混凝土梁承载力将逐渐降低；在逐级加载过程中无论钢筋锈蚀率大小，再生混凝土梁正截面混凝土应变变化仍满足平截面假定要求。基于普通混凝土梁抗弯刚度规范公式，引入钢筋应变不均匀系数的修正系数，建立了锈蚀钢筋再生混凝土梁抗弯刚度的计算方法。［关键词］再生混凝土梁; 锈蚀率; 粘结性能; 抗弯刚度中图分类号：TU375 文献标识码：A 文章编号：1002-848X(2015)10-0049-07Experimental study and rigidity analysis on corroded reinforced recycled concrete beamsCao Fubo1,2， Wang Chenxia1,2， Liu Longgang3， Xin Yaodong4, Li Jinghong5， Tian Zhonggang5(1 Nanjing University of Aeronautics and Astronotics， Nanjing 210016， China； 2 Inner Mongolia University of Science and Technology， Baotou 014010， China； 3 Build Quality Inspection Station of Shanghai Baoye Engineering Technology Co., Ltd., Shanghai 200941, China; 4 Metallurgical Corporation of China Real Estate of Baotou Co., Ltd.，Baotou 014010， China; 5 China Second Metallurgy Group Co., Ltd.， Baotou 014010， China)Abstract:Static loading tests were carried out on 12 recycled aggregate concrete beams with 100% coarse aggregate replacement rate and different corrosion rate. The effects of steel bar corrosion ratio on failure modes, crack development law and load-deflection curves and plane-section assumption of recycled aggregate concrete beams were analyzed. Results show that when the steel corrosion rate is less than 10%, bending ductile failure occurs because the strength of the material is damaged. When the steel corrosion rate is greater than 10%, beam bond-shear brittle failure occurs because bond failure between steel bars and recycled concrete. With the increase of steel corrosion rate, the bond performance between steel bars and recycled concrete increases first and then decreases, but the carrying capacity of recycled aggregate concrete beam gradually decreases. The strain change of the normal section of recycled concrete beam still meets the requirements of plane-section assumption regardless of the rebar corrosion rate in step-by-step loading process. Based on the code formula of concrete beam flexural stiffness, correction factor of steel strain uniform coefficient was introduced，and calculation method of bending stiffness of corroded reinforced recycled concrete beam was established.Keywords:recycled concrete beam; corrosion rate; bond performance; bending stiffness* 内蒙古自治区自然科学基金项目（2014MS0551），内蒙古自治区高等学校科学研究项目（NJZY159），包头市科技计划项目（2014X1009）。通讯作者：王晨霞，博士，副教授，Email：15949488601@139.com。参考文献［1］肖建庄.再生混凝土［M］.北京:中国建筑工业出版社，2007.［2］颜桂云,孙炳楠.锈蚀钢筋混凝土受弯构件抗震性能的试验研究［J］.建筑结构,2003,33(2):16-18.［3］MANGAT P S,ELGARF M S.Flexural strength of concrete beams with corroding reinforcement［J］.ACI Structural Journal，1996,96(1):149-158.［4］牛荻涛,翟彬,王林科.锈蚀钢筋混凝土梁的承载力分析［J］.建筑结构,1999,29(8):23-25.［5］范颖芳,周晶,黄振国.受氯化物腐蚀钢筋混凝土构件承载力研究［J］.工业建筑,2001,31(5):3-5.［6］牛荻涛,卢梅,王庆霖.锈蚀钢筋混凝土梁正截面受弯承载力计算方法研究［J］.建筑结构,2002,32(10):14-17.［7］任宝双,钱稼茹,聂建国.在用钢筋混凝土简支桥面梁受弯刚度估算［J］.工业建筑,2001,31(1):13-15.［8］GB/T 25177—2010混凝土用再生粗骨料［S］.北京:中国标准出版社,2010.［9］仲伟秋,贡金鑫.钢筋电化学快速锈蚀试验控制方法［J］．建筑技术开发,2002,29(4):28-30.［10］GB/T 50152—2012 混凝土结构试验方法标准［S］.北京:中国标准出版社,2012.
