Effect of Beam Length and Braced Length on Moment-Rotation Behavior of Castellated Beams

Mohsen  Gerami; Hamid  Saberi; Vahid  Saberi; Ashkan  Firouzi

doi:10.4236/ojsst.2013.33005

Mohsen Gerami, Hamid Saberi^*, Vahid Saberi, Ashkan Firouzi

Abstract: The presence of web openings in castellated beams introduces different modes of failure at the perforated sections such as excessive stresses in tee-sections, excessive stresses in mid-depth of the web post, web-post buckling, developing plastic Vierendeel mechanism. This paper presents nonlinear behavior of castellated beams under moment gradient loading and investigates the effect of beam length and braced length on moment-rotation behavior and ductility of this type of beams. Accuracy of finite element models of plain-webbed beams is evaluated comparing moment-rotation behavior and failure mode of other researchers’ numerical models and cleared a satisfactory accuracy. Rotational capacity of castellated beams, derived from numerical modeling, is compared with corresponding I-shaped plain-webbed steel beams and it is cleared that for the short beams, web openings reduce energy absorbance and plastic moment capacity of the beams more than long ones.

Keywords: Castellated Beam; Finite Element Method; Rotational Capacity; Braced Length; Monotonic Loading; Numerical Modeling; Moment-Rotation Behavior

Cite this paper: M. Gerami, H. Saberi, V. Saberi and A. Firouzi, "Effect of Beam Length and Braced Length on Moment-Rotation Behavior of Castellated Beams," Open Journal of Safety Science and Technology, Vol. 3 No. 3, 2013, pp. 43-50. doi: 10.4236/ojsst.2013.33005.

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