【摘要】 氯离子导致的钢筋锈蚀具有显著的不均匀性，仅以平均质量损失率为指标难以准确预测锈蚀钢筋及钢筋混凝土结构力学性能的劣化程度。利用3D扫描技术分析锈蚀钢筋形貌特征，首先通过电化学快速锈蚀方法完成钢筋锈蚀，然后采用高精度三维扫描仪进行锈蚀钢筋表面形貌扫描，利用图形处理软件和自编程序计算锈蚀钢筋残余横截面面积，最后进行了残余横截面面积分布特征分析。结果表明：随着锈蚀率的增大，钢筋残余横截面面积不断减小，且残余横截面面积最小值较平均值下降更快；在质量锈蚀率接近时，随着钢筋直径的增大，残余横截面面积最小值与平均值的比值减小，而残余横截面面积标准差增大；锈蚀钢筋残余横截面面积分布随着锈蚀率的变化而变化。更多还原

【Abstract】 The corrosion of steel bars induced by chloride attack is mostly non-uniform,which is highly localized with corrosion pits being randomly distributed both along the longitudinal and transverse sections of the bars.Therefore,it is not quite appropriate to predict the residue properties of corroded steel bars and analyze the RC members in service based on the average mass loss.Three-dimensional(3D) laser scanner was used in this study to research the surface of corroded steel bars accurately.First, an accelerated corrosion was adopted to induce non-uniform corrosion of bare steel bars;then,the surface morphology of corroded steel bars was measured by a method of 3D scanning; lastly, the residual cross section and its probability density distribution with different corrosion ratios along the bar length was analyzed.The results indicated that the residual cross section gradually reduced with the corrosion ratio, and the minimum cross-sectional area reduced with a higher rate than the average values.For the steel bars with similar corrosion ratios,the ratio between the minimum and average value of the cross-sectional area was smaller while the standard deviation was larger for the steel bars with larger diameter;in addition,the distribution of the cross-sectional area varied with the corrosion ratio and the steel bar diameter.更多还原