Influence of Mineral Admixtures and Fibers on Workability and Mechanical Properties of Reactive Powder Concrete

This paper investigates the influence of mineral admixtures and fibers on workability and mechanical properties of reactive powder concrete. Preliminary tests of materials and multiple trial mix designs are carried out to establish a proper control mix of ultrahigh-strength concrete satisfying workability and mechanical properties. Cement is replaced with silica fume and ultrafine ground granulated blast furnace slag (GGBS) in the range of 0%-15%, and sand is replaced with quartz powder in range of 0%-15%. These mixes are investigated individually and in combination for workability and mechanical properties such as compressive strength, split tensile strength, and flexure tests for various curing regimes, namely normal curing, preheat curing, and postheat curing. X-ray diffraction (XRD) analysis investigates the composition responsible for the high mechanical and durability characteristics. The study is extended to improve the ductility of reactive powder concrete by addition of various synthetic and natural fibers to investigate its mechanical properties. The best mix is selected considering the workability and mechanical properties of the reactive powder concrete developed.