Ultimate strength of girders with trapezoidally corrugated webs under patch loading

Ultimate strength of steel plate girders with trapezoidally corrugated webs under patch loading is studied using a non-linear finite element method. Effect of large deflection is taken into account and a von Mises material either without strain hardening (elastic-perfectly plastic), or with strainhardening obeying Ramberg-Osgood's equation, is assumed. The following factors that influence the ultimate strength are investigate (1) strainhardening models; (2) initial imperfections (local and global); (3) variation of yield stress and strain-hardening degree at the corrugation corners due to cold forming, ‘corner-effects’; (4) loading position; (S) load distribution length, and (6) variation of geometric parameters. Based upon the numerical results obtained, an empirical formula for the prediction of the ultimate strength is suggested.