An energy method is developed for analyzing the flexural torsional buckling behavior of flanged stiffeners subjected to axial force.

For symmetrical composite laminated plates including the coupling of bending and twisting with the simply supported or clamped boundary conditions, an identification theory is presented in this paper to assess the five bending rigidities from the modal analysis of vibration.

Wagner effect in flexural-torsional buckling of open-profile thin-walled columns;

The flexural-torsional buckling of thin-wall open compression members with twin axes eccentrically connecting with multiple elastic supports is studied.

Based on the theory of nonlinear finite element of plate and shell,a finite element method of elasto-plastic flexural-torsional buckling of steel members under cyclic loading was presented,and a nonlinear analysis program was complied.

By using the finite element method of structural analysis,on the basis of mechanical theorem and geometric coordinative condition,the coupled flexure-torsion stiffness matrix of the beam element with asymmetric section are derived and a model of cable-stayed bridge for lateral dynamic analysis due to the vehicle is constructed.

Theoretical research and earthquake damage investigation indicate that there is bend torsion coupling vibration for curved bridge when earthquake occurs.