Analysis of beams with large openings using nonlinear finite element procedure

Abstract

The object of this paper was to use a nonlinear plane stress finite element procedure to predict the behaviour of simply supported reinforced concrete beams with a large opening, under mid-span static loading. In the finite element analysis, parabolic isoparametric elements were used in conjunction with the discrete bar formulation. A smeared cracking approach was included and concrete under different states of stress was modelled by using individual models that were incorporated to represent a biaxial state of stress. Reinforcing steel was modelled by using a uniaxial elastoplastic strain-hardening curve. Test results showed that the above approach was found to be satisfactory in predicting the load–deflection curves, crack patterns, and ultimate loads for this type of beam. Key words: beams, cracking, endochronic theory, finite element method, load deflection, nonlinear analysis, openings, reinforced concrete, ultimate load.