Numerical Investigation on Steel Square HSS Columns Strengthened with Polymer-mortar

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Khaled M. El-Sayed
Ahmed S. Debaiky
Nader N. Khalil
Ibrahim M. El-Shenawy


This paper presents the results of finite element (FE) analysis of axially loaded square hollow structural steel (HSS) columns, strengthened with polymer-mortar materials. Three-dimensional nonlinear FE model of HSS slender columns were developed using thin-shell element, considering geometric and material nonlinearity. The polymer-mortar strengthening layer was incorporated using additional layers of the shell element. The FE model has been performed and then verified against experimental results obtained by the authors [1]. Good agreement was observed between FE analysis and experimental results. The model was then used in an extended parametric study to examine selected AISC square HSS columns with different cross-sectional geometries, slenderness ratios, thicknesses of mortar strengthening layer, overall geometric imperfections, and level of residual stresses. The effectiveness of polymer-mortar in increasing the column’s axial strength is observed. The study also demonstrated that polymer-mortar strengthening materials is more effective for higher slenderness ratios. An equivalent steel thickness is also accounted for the mortar strengthened HSS columns to discuss the effectiveness of polymer-mortar strengthening system. The polymer-mortar strengthening system is more effective for HSS columns with higher levels of out-of-straightness. Level of residual stress has a slight effect on the gain in the column’s axial strength strengthened with polymer-mortar.

Finite element, buckling, HSS, column, polymer, mortar.

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How to Cite
M. El-Sayed, K., S. Debaiky, A., N. Khalil, N., & M. El-Shenawy, I. (2019). Numerical Investigation on Steel Square HSS Columns Strengthened with Polymer-mortar. Advances in Research, 20(4), 1-25.
Original Research Article


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