Non-Linear Analysis of Flat Slabs Prestressed with Unbonded Tendons Submitted to Punching Shear

Abstract

This article describes a numerical study for the evaluation of the punching shear behavior of non-adherent prestressed flat slabs without shear reinforcement. Nonlinear three-dimensional models were used, along with the finite element method (FEA) through the ATENA software in order to validate the constitutive models adopted for concrete and steel. The numerical results were compared with the experimental results. The results revealed a good agreement among load capacity, deformations, and cracking panorama, as well as the relation between numerical and experimental failure loads. After validation, a parametric study was carried out to analyze the influence of tendon spacing, slab thickness, and column rectangularity in prestressed flat slabs. Finally, the results obtained in the numerical models in relation to the failure load were compared with the estimated values for the failure load according to the main normative predictions dealing with the flat slab system.