Finite element analysis on eccentric compression of reinforced concrete columns strengthened by prestressed polyethylene terephthalate straps and angle steel

Abstract

To overcome the lagged strain and insufficient stiffness of conventional reinforced structures, this article proposes a reinforcement method realized by combining prestressed polyethylene terephthalate (PET) straps and angle steel. This combined reinforcement method relies on the active restraint force provided by the PET straps and the vertical bearing capacity provided by the angle steel to improve the bearing capacity and ductility of reinforced structures. This article introduces the experimental process applied to the combined reinforced columns. Thereafter, a finite element simulation model of the columns strengthened by prestressed PET straps and angle steel was established on the basis of the experiment. A plastic damage model was used for the concrete. An ideal elastoplastic model was used for the PET straps, angle steel, and steel bars. In the finite element simulation analysis, a multiparameter analysis was conducted on the eccentric distance, packaging distance, and packaging method. The research results showed that as the packing spacing of the PET straps decreases, the confinement area of the column increases, and the load-bearing capacity and ductility of the specimens increase to some extent. With the increase in the eccentricity, the increase in the bearing capacity of the combined reinforced column is less. Nevertheless, there is significant improvement in the ductility performance. Considering the economy and reinforcement effects, the mesh packing method produces the best results. This article introduces parameters such as the restraint stress of the PET straps and the utilization rate of the angle steel. A calculation formula for the small-eccentric bearing capacity of the combined reinforced column was established, providing a theoretical basis for engineering applications.

Experimental study on flexural performance of reinforced concrete beams strengthened by PET

“…Subsequently, Si et al 47 used composite reinforcement and utility model packaging materials to strengthen reinforced concrete columns, showing that prestressed PET‐cladding steel composite reinforcement can effectively inhibit the generation and development of cracks, thereby improving the ultimate bearing capacity of the strength and ductility of components. Based on the test, Si et al 48 established a finite element simulation model of prestressed PET strips and angle steel reinforced columns, carried out the multiparameter analysis of the eccentricity distance, PET spacing, and reinforcement methods, and established a small eccentricity of composite reinforced columns. The bearing‐capacity calculation formula provides a theoretical basis for engineering applications.…”