Stress analysis of linear elastic non-prismatic beams with corrugated steel webs

Abstract An experimental study of a simply supported beam with a cantilever in the elasticity range was conducted for the first time to investigate the distribution of shear stress and normal strain in a non-prismatic beam with corrugated steel webs (CSWs). In the elastic stage, the experimental results are in good agreement with the results of the three-dimensional (3D) finite element analysis for this test beam. The theoretical and experimental results demonstrate that it is not reasonable to assume that the corrugated webs bear all the vertical shear force in a non-prismatic beam with CSWs because of the effect of the variable cross section; this phenomenon is quite different from that in the case of prismatic beams. It would be overly conservative to calculate the shear stress in a non-prismatic beam with CSWs while ignoring the carrying capacity of the concrete flanges (especially the inclined bottom flange). The authors also found that the shear stress in the steel web does not reach its maximum value in the middle-supported section. Namely, the root section is not the most critical section, although it withstands the maximum vertical shear force and hogging bending moment near the middle supports of continuous beams. In addition, the quasi-plane assumption proved to be valid in the test beam, as the normal stress in the concrete flanges is distributed linearly. The longitudinal bending moment is resisted mostly by axial forces in the concrete flanges, and the CSWs offer little resistance to the longitudinal bending moment caused by the accordion effect.