Lateral-torsional buckling of steel web tapered tee-section cantilevers

In this paper an analytical model is presented to describe the lateral-torsional buckling behaviour of steel web tapered tee-section cantilevers when subjected to a uniformly distributed load and/or a concentrated load at the free end. To validate the present analytical solutions finite element analyses using ANSYS software are also presented. Good agreement between the analytical and numerical solutions is demonstrated. Using the present analytical solutions, the interactive buckling of the tip point and uniformly distributed loads is investigated and a parametric study is carried out to examine the influence of section dimensions on the critical buckling loads. It is found that web tapering can increase or decrease the critical lateral-torsional buckling loads, depending on the flange width of the beam. For a beam with a wide flange (width/depth = 0.96) the critical buckling load is increased by 2% by web tapering, whereas for a beam with a narrow flange (width/depth = 0.19) web tapering reduces the buckling load up to10% and 6% for the tip point loading and the uniformly distributed load respectively.