High Performance Reinforced Concrete Beams made with Sandstone Reactive Aggregates

摘要

An investigation on the flexural behaviour of reinforced high performance concrete (HPC) has been conducted.Crushed sandstone known as reactive aggregate was used for both fine and coarse aggregates. In addition, mineraladmixtures such as silica fume and fly ash combined with superplasticiser was used. The beams were made with concretehaving compressive strength in the range of 74 - 88 N/mm2 and tensile reinforcement in the range of 1.34 to 3.14 %. Theexperimental ultimate moment was found to be about 14 - 34 % and 3 - 15 % higher than the predicted ultimate momentbased on BS 8110 and ACI 318 respectively. Due to lower stiffness of reactive sandstone aggregates, the actual deflectionsof the beams were found to be slightly above allowable values under service loads. The observed crack widths underservice loads were within acceptable limits. It was found that HPC made with crushed sandstone coarse and fine aggregatehad better structural integrity. Hence, there is a high potential to produce high strength HPC using sandstone aggregateswith silica fume and fly ash.