Experimental study and finite element analysis of concrete columns with square GFRP tube confined cross stirrups under axial compression

This article investigates the axial compression performance of glass fiber reinforced plastic (GFRP) tube restrained transverse ring reinforced concrete composite columns. Six composite columns were designed for axial compression experiments and subjected to multi condition ABAQUS finite element simulations. Analyzed the effects of constraint width, circumferential spacing, GFRP tube thickness, and concrete strength on the bearing capacity of composite materials, mainly studying the effect of hoop section form on the mechanical properties of composite columns. The results show that the spacing between the stirrups and the width of the constraint on the bearing capacity show a trend of increasing first and then decreasing, with the optimal constraint width being 40–60 mm; Increasing the thickness of GFRP tubes can effectively improve the bearing capacity, but the gain effect weakens with the increase of concrete strength.