Flexural behaviour of ECC-LWC encased slender high strength steel composite beams: Fid-Bau Portal

Flexural behaviour of ECC-LWC encased slender high strength steel composite beams

Kabir, Md. Imran / Lee, C.K. / Rana, Mohammad M. / Zhang, Y.X.

Abstract This paper reports an experimental and numerical study on the flexural behaviour of Engineered Cementitious Composites and Lightweight Concrete (ECC–LWC) encased slender High Strength Steel (HSS) composite beams. Four simply supported slender HSS composite beams with different encasement materials (concrete or ECC–LWC) and configurations (fully or partially encased) were first tested under four–point bending. Three–dimensional nonlinear finite element (FE) models were then developed and validated against the test results. Experimental results obtained showed that the two ECC–LWC fully encased slender beams carried higher loading with improved ductility than the concrete fully encased slender beam. Moreover, test results of the ECC–LWC fully encased slender beams confirmed that the encasement successfully eliminated both local buckling and global lateral torsional buckling of the slender HSS I–section. However, the partially encased beam in which encasement was only applied to the compression flange was failed by lateral torsional buckling before its top flange was yielded. A parametric study was also carried out using the validated FE model to further investigate the effectives of different encasement parameters on the flexural behaviour of ECC–LWC fully encased slender HSS composite beams. Finally, a simplified analytical solution is proposed for estimating the flexural strength of the fully encased beams.

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Highlights • Flexural resistance of ECC-LWC encased slender HSS composite beams are studied • Bending tests were conducted to study the behaviour of encased slender HSS beams • Fully encased beams show no LTB but partially encased beam failed by LTB • A FE model to predict the beam's flexural resistance is developed and validated • A parametric was conducted to study effects of different parameters and analytical solution proposed.