Simplified calculation method for torsion parameters of thin-walled box girder section

A new approach of calculating the geometrical properties of thin-walled box girder section by space finite element analysis software was put forward through analyzing the torsion properties of thin-walled box section member. A space model of cantilever girder was set up whose section was the thin-walled box section for computation. Authors put on a concentrated torsional moment at the end of cantilever. Torsion parameters of thin-walled box section could be calculated according to the neighbouring section torsion angle and section deformation at the end of the girder cantilever. Exactitude section pattern should be input to improve calculation accuracy. It is shown that the calculation result by this method is simple in operation process and has high accuracy. It is easy for users to manage with any well-informed space finite element analysis software.