Bending behavior test of hybrid high performance steel beam

Bending behavior tests were conducted for 3 hybrid high performance HPS 485 W I-shape steel beams with the method of two-point loading.The influences of cross profile geometric parameters on bending capacity, elastic and plastic deformations, and failure mode of test beam were analyzed.Considering the test results under midspan one-point loading, the influences of different loading methods on bending capacity of test beam were analyzed.Finite element models were established to accurately simulate bending procedures of test beams.Parameter analysis was conducted for hybrid high performance steel beams under the condition of non-compact cross profile.Analysis result shows that the failure modes of two-point loading test beams are local bucklings at both compressive flange and compressive web in pure bending field.The plastic rotation capacity of steel beam increases obviously with the decrease of flange width to thickness ratio.The bending capacity and ductility decrease with the increase of web height to thickness ratio.For beams with same dimension, the bending procedures are similar when adopting different loading methods, but the buckling modes marking the failure of beam are different.It is suggested for hybrid steel beam that the steel grade of web should be not beyond two grades lower than the strength grade of flange.