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。
It is a practical non-destructive 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 cross-sectional 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 cross-sectional corrosion area,which is helpful in engineering.