EXPERIMANTAL STUDY OF EFFECT OF HEXAGONAL HOLES DIMENSIONS ON ULTIMATE STRENGTH OF CASTELLATED STEEL BEAM

Abstract

Nowadays, use of castellated steel beams (CSBs) has become very common because of their advantageous implementations in construction of buildings. Castellated Steel Beams (CSBs) are those members that are fabricated from standard hot rolled steel (HRS) I- sections by cutting along its web in "zigzag" pattern and thereafter rejoining the two halves on one another by welding together to form a castellated beam, so that generally the depth of a section will be increased. This research analyses the experimental results of six specimens of castellated steel beams and compares with control beam (Parent section). The purpose of this study is to investigate the effect of hexagonal hole dimensions on the ultimate strength and stiffens response of the castellated steel beam. Also, the effect of number of holes on the behavior of the castellated steel beams that have the same span and ratio of expansion was investigated. All specimens of the castellated steel beam were fabricated from hot rolled steel section (IPE140) and were expanded to (1.56) times the parent section depth. From the test results, it is observed that best dimension of castellated steel beam was (span length to holes space ratio L/S = 8.0); hole depth to Castellated beam depth ratio is h/H=0.56, and hole space to the castellated beam depth ratio is S/H = 1.03. The ultimate strength of the castellated steel beam was increased about (50%) stronger than the original beam.