ABSTRACT
Coatedcrete is designed to satisfy structural requirements and is then coated to provide adequate durability. Over the past five years the use of silane and siloxane penetrating coating systems have been seen as one possible answer to the corrosion of reinforcement problem. However, there are questions as to longevity of the coating system, its cost and to the performance of recoated concrete. It is also difficult to tell whether the whole structure has been coated, to what depth and the consequent resistance to further attack. Coatedrebarcrete is designed to satisfy structural requirements and is used where protection of reinforcement from corrosion only is required. In contrast to the above, the reinforcement itself is coated, eg by zinc or fusion bonded epoxy resin. The close control that can be exercised during manufacture of the coated reinforcement gives rise to more confidence of the in-situ performance of concrete. However, the reinforcement is expensive and needs care during handling and fixing. Any damage may not be detected and could give rise to intense local corrosion attack. There are also unanswered questions regarding bond strength. Efficientcrete is produced to the state of the art using the full potential of the constituent materials by improved construction, workmanship and curing practices, as for example demonstrated in Figures 6 and 7. Such a concrete requires no special consideration other than fully exploiting the potential of already existing materials. It would seem likely that efficientcrete would utilise chemical admixtures and cement replacement materials, together with the use of a high efficiency curing membrane to ensure proper curing. Such a material would not only be cheap in terms of whole life costs in relation to the other options but also only requires improvements and not wholescale changes to current practice.
