Synergic influence of degrading mechanisms and induced loading by prestressing on the concrete: state of the art

Since prestressed concrete is regarded as more durable and reliable than other construction materials, it is used in a variety of civil engineering applications, including nuclear plants, bridges, and concrete piles. However, as with other building structures, prestressed concrete structures are also subjected to different long-term environmental actions, which influence the durability and performance of prestressed concrete structures. Furthermore, it has been found that data on the effect of deteriorating environmental mechanisms on prestressed concrete is scarce. This state-of-the-art review attempts to provide a concise assessment of existing research on the effect of environmental actions such as freezing and thawing, carbonation, and chloride on prestressed concrete's durability. It can be summarised that continuous exposure of prestressed concrete to such aggressive environmental conditions reduces not only their mechanical properties, but also their durability performance is affected; the prestress losses increase rapidly and cause significant damage, and cracking occurs. Furthermore, if subjected to marine exposure, the microcracks and widened cracks may provide pathways for chlorides and other harmful agents to penetrate towards the prestress wires or tendons and subsequently cause corrosion.