Effect of sinusoidal geometry on shear capacity of profiled web girder using finite element method

Abstract

Plate girder is a build up section with a flat web that stiffened transversely and if necessary longitudinally. Profiled web can be alternative solution to eliminate stiffener since the profiled geometry of the web is out of plane and introducing more surface panel compare to flat web. So this research is conducted to study the effect of sinusoidal geometry on shear capacity of profiled web girder. Main objective of this research is to study behaviour of sinusoidal plate girder, effect of the web thickness, effect of the web geometry dimension on shear capacity and compare sinusoidal profiled web capacity with conventional flat girder. Modelling is using sine function as profiled geometry of the web and thin shell element of meshing. Material strain hardening parameter limited only elastic-perfect plastic model. Linear analysis has been done to predict the buckling mode and geometry imperfection. Non linear analysis has been done using the geometry imperfection with automatic increment, total langangrian geometry and Crisfield arch length control. Three buckling mode of the web occur in the study were local, zonal and global. It was found that local buckling of the web occurs at one sinusoidal fold. After reaching peak load the buckling switch to zonal which transfer to the next sine fold in diagonal direction developing tension field action and continue buckle into global mode. Crippling of the web occur at the failure stage and flange buckle vertically into the web. Local failure occur at the fold of the web when the amplitude is to greater and continue buckle until failure without diagonal tension field hence decreasing the ultimate load capacity. Sinusoidal profiled web increasing about 50% loading capacity compare to flat web. Increasing web thickness will decreasing slenderness of the web hence increasing loading capacity. Proportion of amplitude and wave geometry of the sinusoidal influence the slenderness of the web hence affecting the shear capacity.