Numerical prediction of composite beam subjected to combined negative bending and axial tension

The present study has investigated the finite element method (fem) techniques of composite beam subjected to combined axial tension and negative bending. the negative bending regions of composite beams are influenced by worsen failures due to various levels of axial tensile loads on steel section especially in the regions near internal supports. three dimensional solid fem model was developed to accurately predict the unfavourable phenomenon of cracking of concrete and compression of steel in the negative bending regions of composite beam due to axial tensile loads. the prediction of quasi-static solution was extensively analysed with various deformation speeds and energy stabilities. the fem model was then validated with existing experimental data. reasonable agreements were observed between the results of fem model and experimental analysis in the combination of vertical-axial forces and failure modes on ultimate limit state behaviour. the local failure modes known as shear studs failure,excess yielding on steel beam and crushing on concrete were completely verified by extensive similarity between the numerical and experimental results. finally,a proper way of modelling techniques for large fem models by considering uncertainties of material behaviour due to biaxial loadings and complex contact interactions is discussed. further,the model is suggested for the limit state prediction of composite beam with calibrating necessary degree of the combined axial loads. © school of engineering,taylor's university.