Finite Element Study on Punching Shear Behavior of Continuous Bubbled Reinforced Reactive Powder Concrete Slab

Abstract

This paper presents a nonlinear finite element analysis on punching shear behavior of continuous bubbled reinforced Reactive Powder Concrete (RPC) slabs using ABAQUS (6.14-4) computer program. Nine different bubbled slab specimens were modeled to study the effect of certain parameters on the punching shear behavior of the slabs. The parameters included type of the concrete (RPC and Normal Concrete (NC)), the effect of bubbles which are created practically by using recycled spherical balls, their diameter and their locations. In these models a nonlinear material's behavior for concrete slab and steel reinforcement was simulated using appropriate constitutive model. The adapted model was validated by using data from experimental test. The analytical results showed that the ultimate load carrying capacity and the maximum central deflection depends on the specified parameters where by increasing bubbles diameter to slab thickness (D/t) ratio from 0.6 to 0.7 the ultimate load along with central deflection decreased by (6.63 %) and (6.49 %), respectively. The solid slab test shows that the usage of bubbles to decrease the self-weight of the slab will slightly decrease the total strength of the slab, where the ultimate load in solid slab increased by (5.28 %) compared to the bubbled slab. Also, for slabs with bubbles at 2D and 3D the ultimate load increased by (14.71 %) and (8.76 %), respectively compared to slab with bubbles at all area for slabs with (D/t) ratio of 0.6 and by (30.85 %) and (27.65 %) for slabs with (D/t) ratio of 0.7. Furthermore, it was found that using RPC will significantly increases the ultimate load compared to NC about (111.95 % - 118.6 %) for different (D/t) ratios.