Yield Design of Reinforced Concrete Slabs Using a Numerical Equilibrium Formulation

Abstract

This paper presents a numerical procedure based on equilibrium finite elements and conic programming for plastic collapse load computation of reinforced concrete slabs governed by the Nielsen yield criterion. Bending moment fields are approximated using the enhanced Morley elements with an added second-degree moment field, allowing exact equilibrium relations to be achieved when applying a uniform pressure to the slabs. Conic programming, which is robust and efficient, is incorporated into the obtained discrete equilibrium formulation to ensure solutions can be obtained rapidly. Several slabs of arbitrary geometries and boundary conditions are examined, providing accurate collapse load multipliers and distributions of moment fields at the limit state.