深圳大学学报理工版

外加电流加速锈蚀是钢筋锈蚀研究中广泛应用的方法.为探究外加电流在钢筋加速锈蚀过程中的实际消耗,通过微米级X射线计算机断层扫描(X-ray computed tomography,XCT)技术对砂浆试块内钢筋的通电加速锈蚀过程进行跟踪测试,实现不同阶段钢筋锈蚀质量损失的量化,进而获得各个阶段电流有效系数.试验结果表明,XCT技术可进行钢筋锈蚀过程的无损跟踪、锈蚀形貌表征和锈蚀参数量化.通过量化电流有效系数可得,受钢筋脱钝、电解水反应和钢筋自然锈蚀的影响,不同锈蚀阶段的电流有效系数存在差别.保护层在开裂前发生钢筋脱钝和电解水反应,电流有效系数偏低; 开裂后由于钢筋自然锈蚀,电流有效系数偏高.

Impressed-current accelerated corrosion has been widely used in the study of steel corrosion. To investigate the actual consumption of impressed current during the accelerated corrosion process, micro-level X-ray computed tomography(XCT)technique is employed to trace the accelerated corrosion process of steel in a mortar sample to quantitatively analyze the mass loss of steel at different stages, with which current effective coefficient of each stage can be further calculated. The experiment results show that XCT technique can achieve non-destructive tracking of the corrosion process, visual characterization of corrosion morphology, and quantitative calculation of corrosion parameters. The calculation of current effective coefficient indicates that due to the influence of depassivation of steel, electrolysis of water and natural corrosion, the current effective coefficient varies in different corrosion stages. Before the cracking of concrete cover, depassivation and electrolysis lower the coefficient. After cracking, the coefficient is magnified by natural corrosion.

引言
1 试验
2 试验结果
3 结论

图1 试块尺寸和实拍图(单位:mm)<br/>Fig.1 Size and photo of the sample(unit: mm)

图1 试块尺寸和实拍图(单位:mm)
Fig.1 Size and photo of the sample(unit: mm)

图2 通电加速锈蚀试验装置图<br/>Fig.2 Equipment of current accelerated corrosion test

图2 通电加速锈蚀试验装置图
Fig.2 Equipment of current accelerated corrosion test

表1 通电时间安排
Table 1 Time arrangement

图3 XCT检测结果<br/>Fig.3 XCT testing results

图3 XCT检测结果
Fig.3 XCT testing results

图4 试块锈蚀形貌变化<br/>Fig.4 Change of sample corrosion morphology

图4 试块锈蚀形貌变化
Fig.4 Change of sample corrosion morphology

图5 钢筋锈蚀质量损失变化<br/>Fig.5 Change of mass loss of steel corrosion

图5 钢筋锈蚀质量损失变化
Fig.5 Change of mass loss of steel corrosion

图6 各阶段电流有效系数<br/>Fig.6 Current effective coefficient of each stage

图6 各阶段电流有效系数
Fig.6 Current effective coefficient of each stage

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备注

引言

1 试验

2 试验结果

3 结论

期刊信息

备注

引言

1 试 验

2 试验结果

3 结 论

期刊信息

1 试验

3 结论