Repair of concrete crack by pulse electro-deposition technique

•The pulse electro-deposition method in repair of concrete cracks is studied.•The healing effect were compared between using pulse and direct current.•The composition, morphology and developing process of deposit are analyzed.

Electro-deposition is a new technique that has been developed recently to rehabilitate cracked reinforced concrete. While pulse current has been proven to be superior to direct current in the electro-deposition method, there is lack of research on applying pulse current electro-deposition method in repair of concrete cracks. Using electro-deposition method with two different types of current, this study investigated the healing effect of reinforced concrete cracks, and the behavior was compared between pulse current and direct current. The results indicate that using pulse current brings a better healing effect in terms of higher ratios of weight gain, surface coating, crack closure and crack filling depth. In addition, X-ray diffraction and scanning electron microscopy were used to assess the effectiveness of the electro-deposition method, and it is found that the pulse current has no impact on the composition of the sediments, but changes the morphology.