Preparation and Dynamic Tensile Behavior of C200 Green Reactive Powder Concrete

A new type of green reactive powder concrete (GRPC) with compressive strength of 200 MPa is prepared by utilizing composite mineral admixtures, natural fine aggregates, and short and fine steel fibers. The quasi-static mechanical properties (mechanical strength, toughness, fracture energy and interfacial bonding strength) of GRPC specimens, cured in three different types of regimes, are investigated. The experimental results show that the mechanical properties of the C200 GRPC made with the powder binders that is composed of 40% of Portland cement, 25% of ultra fine slag, 25% of ultra fine fly ash and 10% of silica fume are better than the others’. The corresponding compressive strength, flexural strength and fracture energy are more than 200 MPa, and 30 000 J/ m2 respectively. The dynamic tensile behavior of the C200 GRPC is also investigated through the split Hopkinson pressure bar (SHPB) according to the spalling phenomenon. The dynamic testing results demonstrate that strain rate has an important effect on the dynamic tensile behavior of GRPC. With the increase of strain rate, its peak stress and relevant strain increase. The GRPC exhibits an excellent strain ratio stiffening effect under the dynamic tensile load with high strain ratio, resulting in a significant change of the fracture pattern.