Flexural behaviour of steel beams with double corrugated webs: Experimental and analytical investigations

Corrugated web steel beams (CWSBs) have been widely used in engineering structures due to the benefits of light weight and superior bearing capacity. Normally, traditional CWSBs where prefabricated floor slabs are installed on the top flange of the steel beams, resulting in the reduction of ceiling height, and increasing waste of available space and material. In view of this, an innovative steel beam with double corrugated webs (SBDCW) which can be applied in ordinary frame and heavy-duty frame structures, was developed to solve the above typical limitations for conventional CWSB structures. To investigate the effect of thin-walled corrugated steel webs (TCSWs) on the flexural of SBDCWs, flexural tests of seven specimens while varying the critical parameters were conducted to reveal the failure modes of SBDCWs and collaborative work mechanism between TCSWs and flanges. The test results showed that there was a shear lag effect in steel flanges, and the accordion effect of TCSWs was observed based on the strain analysis of web. Subsequently, a finite element model was developed and a parameter study was also conducted to further evaluate the influences of web thickness, web angle and beam height on the flexural behavior of SBDCWs. Furthermore, an analytical method for predicting the ultimate flexural capacity of SBDCWs was proposed fully taking into account the shear lag effect of flanges, contribution and accordion effect of TCSWs. The calculated results were in good agreement with the test and FEA values, indicating that the proposed methods can accurately predict ultimate flexural capacity of SBDCWs. In summary, this research can provide references and foundations for the design, investigation and application of thin-walled CWSBs in ordinary and heavy-duty frame structures.