1.青岛农业大学建筑工程学院;2.宁波大学土木工程与地理环境学院
TU528.1? ?
国家自然科学基金项目（52178223,51778302）
1.College of Civil Engineering &2.Architecture,Qingdao Agriculture University;3.School of Civil &4.amp;5.Environment Engineering and Geography Science,Ningbo University;6.School of Civil & Environment Engineering and Geography Science, Ningbo University
The National Natural Science Foundation of China（52178223,51778302）
为探究碳化作用下带裂缝混凝土的钢筋腐蚀特征，通过控制裂缝参数，研究了碳化作用下带裂缝混凝土的碳化规律，明确了钢筋腐蚀面积率、失重率和电化学腐蚀参数特征.结果表明：养护早期带裂缝水泥硬化浆体的裂缝宽度相较于水灰比对钢筋腐蚀的影响更为显著，养护后期裂缝宽度对钢筋腐蚀的影响仍逐渐增加，裂缝宽度对钢筋腐蚀的影响占主导地位.碳化作用下带裂缝水泥硬化浆体的Nyquist图存在两个容抗弧，随着碳化龄期增加，低频区容抗弧逐渐收缩，钢筋表面双电层的传递电阻降低，钢筋开始脱钝.在一定的裂缝宽度范围内，水灰比较小时，可以抑制钢筋腐蚀.研究碳化对带裂缝混凝土中钢筋腐蚀的影响有助于完善钢筋混凝土无损检测技术.
In order to explore the corrosion characteristics of steel bars in cracked concrete under carbonation, the carbonation law of cracked concrete under carbonation was studied by controlling the crack parameters, and the characteristics of corrosion area rate, weight loss rate and electrochemical corrosion parameters of steel bar were clarified. The results show that the crack width of the hardened cement paste with cracks in the early stage of curing has a more significant effect on the corrosion of steel bar than the water-cement ratio, and the influence of the crack width on the corrosion of steel bar gradually increases in the later stage of curing, and the influence of the crack width on the corrosion of steel bar is dominant. There are two capacitive arcs in the Nyquist diagram of a cracked hardened cement paste under carbonization. As the age of carbonization increases, the capacitive arc resistance in the low-frequency region gradually shrinks, the transfer resistance of the electric double layer on the surface of the steel bar decreases, and the steel bar begins to remove the passivate film. Within a certain range of crack width, when the water- cement ratio is small, it can suppress the corrosion of the steel bar. The investigation into the impact of carbonization on the corrosion of cracked reinforced concrete is valuable for enhancing the non-destructive testing technique of reinforced concrete.
