Preserving Reinforced Concrete
Free (open access)
A. Foster, C. Atkins & L. Buckley
There is some debate as to when reinforcement was first added into concrete. Most concur that the Parthenon in Rome was fibre reinforced with animal hair almost 2000 years ago. After this, there is a difference of opinion between the French and the British as to the first iron reinforcement in the mid 1800s, with both claiming precedent. The first formally designed systems for reinforced concrete date from the 1900s produced by Hennebique and Mouchel. Early reinforced concrete structures are now falling within the remit of heritage structures, for example the Liver Building in Liverpool dates back to 1908 and is located on a UNESCO world heritage site. As time passes more and more post war structures are becoming recognised for their uniqueness and achieving protected status. This naturally includes increasingly large numbers of reinforced concrete structures. This paper discusses the various degradation mechanisms of reinforced concrete and methods of protection available. In addition the sustainability arguments for preserving rather than replacing concrete structures are highlighted, regardless of the aesthetics. Keywords: reinforced concrete, corrosion, repair, sustainability. 1 Introduction Formally designed reinforced concrete structures are part of our heritage, and are becoming recognised as such. However, durability has only been considered as an issue within design codes within the last 30 years (although corrosion of reinforcement was identified as a problem as early as 1910 ). The fact that any reinforced concrete structures are durable was not an original design consideration, but more a happy coincidence or side effect. The result of this is that a large number of the reinforced concrete heritage is in an increasingly poor condition. This paper presents a review of the historical systems that were in use,
reinforced concrete, corrosion, repair, sustainability.