混凝土中钢筋空间锈蚀特征参数的测试及分析

通过45个混凝土试件中135根光圆钢筋和带肋钢筋的加速锈蚀试验,采用研发的钢筋空间锈蚀形态测试装置和空间锈蚀特征参数分析方法,确定了混凝土中钢筋的空间锈蚀形态图像和空间锈蚀特征参数,进而定量分析了钢筋的质量锈蚀率与最大锈蚀深度、最小剩余截面积、最大截面锈蚀率和点蚀因子等空间锈蚀特征参数之间的相关性,为准确描述混凝土中钢筋的空间锈蚀分布形态提供了基础.结果表明:随着钢筋质量锈蚀率的增加,其最大锈蚀深度和最大截面锈蚀率呈线性增大,而最小剩余截面积和面积点蚀因子呈线性减小;随着钢筋最大锈蚀深度的增加,其最小剩余截面积呈线性减小;与光圆钢筋相比,带肋钢筋的非均匀锈蚀程度更高;与深度点蚀因子相比,钢筋面积点蚀因子与质量锈蚀率之间的相关性更加明显.

Test and Investigation on Spatial Corrosion Characteristic Parameters of Reinforcement Bar in Concrete

Accelerated corrosion test on 135 deformed and plain reinforcement bars embedded in 45 concrete specimens was performed. Subsequently, the image of spatial corrosion profiles and characteristic parameters of reinforcement bar were determined based on the invented test device for image of spatial corrosion profiles of reinforcement bar and the computation method for spatial corrosion characteristic parameters. Finally, the correlation between mass loss ratio and other spatial corrosion characteristic parameters including the maximum corrosion depth, the minimum residual cross sectional area, the maximum cross sectional loss ratio and pitting corrosion factors was quantitatively investigated, which provides a basis to describe the spatial corrosion profile of reinforcement bar in concrete. Analysis results show that the maximum corrosion depth and the maximum cross sectional loss ratio increase linearly with the increase of mass loss, while theminimum residual cross sectional area and the area pitting corrosion factor decrease linearly with the increase of mass loss ratio; theminimum residual cross sectional area decreases linearly with the increase of the maximum corrosion depth; furthermore, degree of non uniform corrosion of the ribbed bar is more serious than that of the plain bar; moreover, the correlation between the mass loss ratio and the area pitting corrosion factor is higher than that with the depth pitting corrosion factor.