Nonlinear finite element analysis of simply supported composite beams stiffened with steel channel

Abstract

A composite beam is an accumulation of differentmaterials so as to form a single unit to exploit the prominentquality of these materials according to their position within thecross-section of the composite beam. The present studyinvestigates the structural behavior of six simply supportedcomposite beams, in which a reinforced concrete T-beam isconnected together with a steel channel located at the bottomof a T-beam by means of headed stud shear connectors. Theused degrees of shear connection are (100%, 75%, 50%, and38%). Three dimensional nonlinear finite element analysis hasbeen used to conduct the numerical investigation for thegeneral behavior of beams which are subjected to central pointload. ANSYS 12.1 program code was used to estimate theultimate loads, deflections, stresses, strains, end slip. Concretewas modeled by brick element (SOLID65), while the steelchannel was modeled as a brick element (SOLID45). Two-nodediscrete elements (LINK8) are used to represent the steelreinforcement and shear connectors. The perfect bond between thereinforcing rebars and the concrete was assumed. The load onbeams was applied monotonically in increments up to failure.The reduction of the degree of shear connection from 100% to38% causes increasing of strain, mid-span deflection and endslip with an average of 3.95%, 13%, and 111% respectively,while the ultimate load decreases with an average of 7.3%. Inorder to observe the efficiency of the 3-D model, a comparisonwas made with available experimental work. Good agreementwas obtained throughout this work between the finite elementand available test results.