NUMERICAL ANALYSIS FOR PUNCHING SHEAR RESISTANCE OF FLAT SLABS BY SHEAR HEADS

Badawy M. M, Saafan M, Elwan S.K, Elzeiny S.M, Abdelrahman A.A.

Abstract: This research presents a numerical analysis for punching shear resistance of flat slabs by shear heads. The results of thenumerical study demonstrated the efficiency of the proposed nonlinear finite element (NLFE) model by close matching the carrying capacity of the tested slab specimensin Ph.D.thesis [1] and their comparative analyzed by the ANSYS program. The analytical program included representingten specimens withthree different column aspect ratio (1:1), (2:1) and (4:1) and two different lengths of steel shear head sections from column face (L1=1.75h and L2=2.25h) where (h) is flat slab thickness. The comparison revealed the accuracy of the analytical model in the representation of flat slabs whoever with or without steel shear head sections; including predicting the punching shear failure load, the behavior of these slabs, in addition to the crack pattern, strains of thebottom steel reinforcement and strains, shear stresses of shear heads. While the model is slightly satisfactory and reliable in predicting the punching failure load of flat slabs with and without steel shear heads. Both of ANSYS program and American code ACI 318-14[2] were used to investigate the punching shear resistance of flat slabs by shear heads. Based on the results of this analytical study, a proposed equation for calculating the punching shear capacity of flat slabs with shear heads was proposed. This equation can be utilized in the design of such flat slabs that connected with columns having the same aspect ratio.

Keywords: Punching Shear, Flat Slabs, Embedded Steel Shear Heads, Finite element modeling,ANSYS program, predicting punching Shear Failure Load.

DOI: https://doi.org/10.15623/ijret.2018.0707009