The shear and flexural behavior of cold-formed steel composite I and U beams

Document Type : Article


1 Department of Civil Engineering, Engineering Faculty, Ataturk University, Erzurum, 25030, Turkey

2 Department of Civil Engineering, Engineering and Architecture Faculty, Erzurum Technical University, Erzurum, Turkey


The recycling and re-usability of the waste materials are of great importance and meaning when evaluated in terms of ecological order. Furthermore, cold formed steel has great importance, nowadays. The aim of this study is to investigate the bending and shear behavior of the composite formed by pouring the waste polymer into the cold formed I and U profile melds after homogenous pulping. The best results in shear and bending strengths were obtained with melted polypropylene. The enhanced adherence between the steel and molted PP increased the shear and bending capacity, both. Moreover, it is reinforced with carbon fiber reinforced polymer and glass fiber reinforced polymer bars to increase the bending and shear behavior of I and U profiles filled with melted waste polymer. Changing the cross-sectional area in I and U beams under bending moment has an effect on the load at yielding, ultimate strength, displacement values corresponding to these loads, ductility and energy dissipation capacity. The addition of CFRP in I beams significantly increased the displacement capacity in the free end region under the shear force. The addition of GFRP bars with higher elongation capacity in I and U beams caused ductile behavior than CFRP bars.


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