Numerical Study of Lateral – Torsion Stability of Thin – wall Beams with Cut–out in Web

Document Type : Research Article



One of the main challenges in designing of thin-walled open section beams is lateral-torsion buckling mode. Due to the access for piping, electrical and other devices, inserting cut-outs in web are inevitable.
This paper deals with the effects of different parameters in lateral-torsion buckling of plate girders. Lateral-torsion buckling loads of more than 700 plate girders are calculated with opening in different shapes, dimensions and locations by Ansys5.4 . The study is performed using numerical approach and the results are compared together. Three kinds of cut-outs including square, circular and hexagonal are selected. An extensive parametric studies is conducted to study the influence of cut-out dimensions, thickness, area, location and distribution along the beam length. Finally optimum scheme is obtained in order to have better estimation load carrying capacity of open-section beam.


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