Residual strength capacity of reinforced reactive powder concrete two-way slabs subjected to drop weight

Abstract

This paper presents an experimental investigation of the effect of the impact force on the residual strength capacity of simply supported reactive powder slabs. Eight specimens of reinforced reactive powder concrete slabs with dimensions of 500 x 500 mm and 70 mm in four categories were used. The influences of slab compressive strength (conventional concrete and reactive powder concrete), steel fiber proportion (1, 1.5, and 2%), percentage of reinforcement in the tension zone (ρ1=0.007, ρ2=0.011, ρ3=0.0179), and the number of impacts (two impacts, four impacts, and six impacts) were all investigated in this test. Investigations were carried out to ascertain each slab's residual response, including first cracking load, residual failure load, residual steel reinforcement strain, maximum central deflection, and crack pattern. The results showed that using reactive powder concrete instead of normal concrete increased the mechanical properties of concrete and resulted in a significant increase in failure load. In addition, the central deflection and strain increased. Increasing the reinforcement ratio increased the failure load while simultaneously decreasing the deflection due to the improvement in slab moment resistance. Furthermore, it was discovered through experiments that the addition of steel fiber to the mixture enhanced the slab’s post-cracking reactivity. The presence of steel fiber raised the slab strength resistance by 21.63% as the steel fiber ratio increased from 1% to 2%. This is because the addition of steel fiber increased the slab's tension resistance.