Abstract

This article proposes an approach to determine the confinement coefficient of concrete columns with square and rectangular cross sections wrapped with all types of fiber-reinforced polymer (FRP) based on soft computing. Five inputs, including the length or longer side of the column, radius of the corner, elastic modulus of FRP, total thickness of FRP, and the ratio of the ultimate tensile strength of FRP to the compressive strength of unconfined concrete, are used as predictors to estimate the confinement coefficient of concrete columns wrapped with FRP. The model was trained and validated based on a set of experimental data. The equations based on the proposed approach were determined and the steps to calculate the confinement coefficient were presented. The results indicated that the extracted equations of the proposed approach have a high degree of precision in comparison with existing models.

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