A new generation of high performance concrete: Concrete with autogenous curing

The literature and site data on the efficiency of curing are controversial regarding its effect on the mechanical properties of high strength concrete. The traditional methods of curing may fail in cases of concrete with a low water/binder ratio and with addition of silica fume. Hydration proceeds quickly, the hydrated cement paste is very dense, and water from the outside cannot reach the interior of the concrete to achieve complete hydration. Replacing 25% by volume of the aggregates by prewetted lightweight aggregates creates water storage inside the concrete, which supports continuous wet curing. The purpose of this article is to introduce a new type of high performance concrete. The materials used and their properties are shown, and the mixing procedure is given. The most important mechanical properties of the concrete under various curing conditions and the microstructure of the hardened cement paste were investigated. The results show that the method of introducing a water reservoir can be successfully applied to obtain high performance concrete with improved properties while being relatively insensitive to curing. (C) 1997 Elsevier Science Ltd.