Finite element analysis of the effect M-V ratios on punching shear strength of edge slab column connections of flat plate structure

The occurrence of unbalanced moment in edge slab-column connections of flat plate structure cannot be avoided and increase the slab shear stress around the column. This paper investigates the effect of M/V ratio on punching shear strength of edge column-slab connections using finite element analysis. The Concrete Damage Plasticity (CDP) and truss model in Abaqus were used to model the nonlinear behavior of concrete and reinforcement, respectively. Ten values of the M/V ratio were applied to a subassembly edge connection model which was part of a properly design of a 5 story flat plate structure. The shear strength prediction of ACI 318-14 code on the effect of unbalanced moment in edge column-slab connection was also studied. The analysis results show that the effect of unbalanced moment on shear strength is not significant for M/V ratio less than 0.3. However, for M/V ratio greater than 0.3, the shear strength is reduced in an exponential order. The ACI 318-14 code overestimates prediction on connection’s shear strength for the M/V ratio less than 0.3. The code predictions are in a good agreement with the analysis results for the edge connection with the M/V ratio greater than 0.3.