In this study, the bond behavior of corroded reinforced concrete was investigated by conducting pull-out tests on concrete specimens with variable induced crack widths and different splitting modes. To simulate cracks due to corrosion and focus on their effect on bond strength degradation, a novel method using expansion agent filled pipes is proposed. With the increase of the crack width over elapsed time from filling the aluminum pipe with an expansion agent, a target crack width was obtained. The results confirm that the type of splitting greatly influences the reduction in bond strength with deterioration of bond strength more severe in “Side-split” than in “Single-split.” Furthermore, using the surface crack width as a variable, empirical formulas to predict bond strength degradation due to corrosion of rebar are proposed. These prediction models give a good correlation when compared to the available literature.

中文翻译：

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膨胀剂填充管开裂混凝土的粘结强度降低

在这项研究中，通过对具有可变诱导裂缝宽度和不同分裂模式的混凝土试件进行拉拔试验，研究了腐蚀钢筋混凝土的粘结行为。为了模拟由于腐蚀引起的裂纹并关注它们对粘合强度降低的影响，提出了一种使用膨胀剂填充管道的新方法。随着用膨胀剂填充铝管随时间推移裂纹宽度的增加，获得了目标裂纹宽度。结果证实，劈裂的类型对粘结强度的降低有很大影响，“侧劈”比“单劈”的粘结强度劣化更严重。此外，使用表面裂纹宽度作为变量，提出了预测由于钢筋腐蚀引起的结合强度退化的经验公式。