Structural Deterioration Mechanisms

This chapter aims to provide a state-of-the-art summary of research topics related to the physical, chemical, and mechanical processes involved in degradation mechanisms of concrete and steel structures located in severe environments. Although several factors affect the deterioration mechanisms of concrete and steel structures, this review mainly focuses on the effects of structural deterioration at the component and system levels. For concrete structures, the chapter investigates the effects of carbonation, chloride, frost, and chemical attacks, as well as alkali-aggregate reaction on material deterioration. In addition, it discusses the steel deterioration owing to corrosion and/or fatigue. The chapter further describes the effect of reinforcement corrosion on structural resistance deterioration. The analytical methods used to evaluate structural resistance deterioration must consider the reduction of the steel bar volume, cracking of the concrete cover because of corrosion product expansion, bond degradation between the concrete and steel, and nonuniformity of corrosion along the steel bars in RC members.