The Effect of Chloride-Induced Corrosion Patterns on the Crack Width of Reinforced Concrete

Sammanfattning: This master's thesis investigates cracking in a parking garage, with a particular focus on the influence of corrosion. Concrete structures commonly experience cracking, and corrosion has emerged as one of the primary contributing factors. These cracks, varying in size and shape, can be considered structural discontinuities. Interestingly, the radius at the bottom of the crack is never zero, indicating that some cracks may be inherent characteristics of the concrete. A fundamental understanding of the crack formation process is crucial as cracks in concrete structures can raise legitimate concerns. Corrosion can weaken the concrete by reducing its performance and result in the delamination of the reinforced concrete cover if cracks and damaged reinforcement are not addressed. This is because corroded steel expands, thereby weakening the surrounding concrete and causing crack formation. In this master thesis, a parking garage with corrosion damage and cracks was examined. Repairing cracks in concrete structures caused by corrosion is a costly process, and globally, over 100 billion dollars are spent annually to address damages caused by reinforcement corrosion. By investigating the corrosion phenomenon within concrete structures in a parking garage, the significance of considering corrosion patterns was identified. The results demonstrated that reinforcement corroding uniformly around the perimeter resulted in larger cracks at the serviceability limit state compared to uneven corrosion from below. This highlights the importance of considering the corrosion pattern when assessing damaged concrete. This master's thesis examines the consequences of unilateral versus uniform corrosion of reinforcement in concrete structures and its impact on crack size. The objective is to elucidate the relationship between corrosion patterns and crack width to develop effective strategies for preventing and repairing damage.