Producing sustainable modified reactive powder concrete using locally available materials

Although extensive investigations have been carried out to produce reactive powder concrete (RPC), the majority of these investigations were conducted based on using fine sand with a maximum particle size of 600 microns and cured under certain conditions. Crushing and grinding processes applied to obtain smaller aggregate sizes and applying heat curing require consuming more energy, which may dramatically affect the cost of production and limit the applicability of this concrete. Thus, this paper mainly aims to assess the performance of RPC made from more cost-efficient sand (i.e., 5 mm fine aggregate) and cured under ambient conditions. For this purpose, a total of twelve mixes (nine with steel fibers and three without) were designed using the local materials to investigate the physical, mechanical, and durability performance of the produced RPC. Moreover, the influence of three different parameters namely, cement content (800, 850 and 900 kg/m3), silica fume ratio as a replacement to cement (0%, 15% and 25%), and steel fibers ratios (0% and 2%) on the performance of RPC was also studied. Water and superplasticizer ratios were kept constant at 0.18 and 4% of the cement weight, respectively. The results highlighted that the RPC produced from local materials using 5 mm maximum size of quartz sand was very efficient and the mechanical and durability properties were comparable to those commonly made from fine sand (600 microns), even under normal curing, giving a higher the possibility for applying RPC in construction applications. Moreover, the hybrid use of silica fume and steel fiber in producing RPC led to significant improvement in all tested properties (mechanical/durability), while only a reduction in the flowability of the mixes was noted by the inclusion of steel fiber.