基于钢筋锈损截面面积的锈胀裂缝宽度计算模型
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王晓刚，杜相波(烟台大学土木工程学院, 烟台 264005)［摘要］通过锈胀裂缝宽度预测混凝土结构中钢筋锈蚀程度是一种实用的非破损检测方法。然而，针对此问题的研究采用的方法不一、参数各异，所得的结论和所建立的计算模型之间也存在较大分歧。针对大量相关研究成果进行综合分析发现，锈胀裂缝的发展与局部区域内锈蚀产物的绝对生成量之间存在直接关系，锈胀裂缝宽度随着平均锈损截面面积的增大近似成线性增大，混凝土保护层厚度和钢筋直径对其无明显影响。通过锈蚀钢筋的三维扫描建立虚拟模型，建立区段最大截面锈蚀率与平均锈蚀率的转换关系。在此基础上综合已有自然锈蚀数据，建立了基于钢筋平均锈损截面面积的锈胀裂缝宽度计算公式，可对实际工程锈胀混凝土构件中的钢筋锈蚀程度给出合理估测。［关键词］混凝土； 钢筋锈蚀； 裂缝宽度； 锈损截面面积中图分类号：TU375文献标识码：A文章编号：1002848X(2013)12005205Calculation model of expansive crack width based on crosssectional corrosion area of steel barsWang Xiaogang, Du Xiangbo(School of Civil Engineering, Yantai University, Yantai 264005, China)Abstract:It is a practical nondestructive method to assess the corrosion state of corroded concrete elements by measuring expansive cracking width. Various methods have been tried to set up the relationship between the crack width and corrosion variables. However, different variables including corrosion penetration depth, weight loss ratio and rebar section loss were introduced by different researchers, and no consistent model has been built up. Available relevant results were collected and analyzed comprehensively. Results show that evolution of expansion cracking relies mainly on the scale of corrosion in a local region and crack width increases linearly with increasing of the average crosssectional area loss. Crack width is hardly influenced by cover depth or rebar diameter. Conversion between regional maximum corrosion ratio and average corrosion ratio was achieved by virtual modeling using 3D laser scanning technology. Based on this method, available test results can be integrated to establish the relationship between expansive crack width and average crosssectional corrosion area, which is helpful in engineering.Keywords:concrete; steel bars corrosion; crack width; crosssectional corrosion area*国家自然科学基金项目（51108400），山东省优秀中青年科学家科研奖励基金项目（BS2010SF027）。作者简介：王晓刚，博士，副教授，Email:wxgnet@163.com。参考文献［1］WANG X G, GU X L, Strengthening of corroding reinforced concrete beams by means of CFRP laminates［J］. Restoration of Buildings and Monuments, 2010, 16(1): 4756.［2］BHARGAVA K, GHOSH A K, MORI Y, et al. Analytical model for time to cover cracking in RC structure due to rebar corrosion［J］. Nuclear Engineering and Design, 2006, 236(11): 11231139.［3］ZHENG J J, LI C Q, LAWANWISUT W. Crack width due to corroded bar in reinforced concrete structures［J］. International Journal of Materials & Structural Reliability, 2005, 3(2): 8794.［4］KIANI K, SHODJA M H. Prediction of the penetrated rust into the microcracks of concrete caused by reinforcement corrosion［J］. Applied Mathematical Modelling, 2011,35(5): 25292543.［5］王巧平, 吴胜兴. 锈裂混凝土裂缝开展的模拟试验研究［J］. 混凝土与水泥制品, 2006(5): 1618.［6］MOLINA F J, ALONSO C, ANDRADE C. Cover cracking as a function of rebar corrosion: part 2─numerical model［J］. Materials and Structures, 1993, 163(26): 532548.［7］ZHAO Y X, YU J, HU B Y, JIN W L. Crack shape and rust distribution in corrosioninduced cracking concrete［J］. Corrosion Science, 2012, 55: 385393.［8］ALONSO C, ANDRADE C, RODRIGUEZ J, et al. Factors controlling cracking of concrete affected by reinforcement corrosion［J］. Material and Structures, 1998, 31(8): 435441.［9］施志业, 郑建军, 周欣竹. 混凝土保护层锈胀裂缝扩展规律试验研究［J］. 甘肃水利水电技术, 2010,46(3):1618.［10］MULLARD A J, STEWART G M. Corrosioninduced cracking: new experimental data and predictive model［J］. ACI Structural Journal, 2011, 108(1): 7179.［11］VIDAL T, CASTEL A, FRANCOIS R. Analyzing crack width to predict corrosion in reinforced concrete［J］. Cement and Concrete Research， 2004, 34(1): 165174.［12］ZHANG R J, CASTEL A, FRANCOIS R. Concrete cover cracking with reinforcement corrosion of RC beam during chlorideinduced corrosion process［J］. Cement and Concrete Research, 2010(40): 415425.［13］RODRIGUEZ J, ORTEGA L M, CASAL J, et al. Corrosion of reinforcement and service life of concrete structures［J］. Durability of Building Materials and Components, 1996, 7(1): 117126.［14］GONZALEZ J A, ANDRADE C, ALONSO C, et al. Comparison of rates of general corrosion and maximum pitting generation on concrete embedded steel reinforcement［J］. Cement and Concrete Research, 1995, 25(2): 257264.［15］袁立群. 混凝土结构锈胀裂缝分析与钢筋锈蚀预测研究［D］. 西安：西安建筑科技大学, 2007.
