Compressive performance of CFSTs strengthened with BFRP textile-reinforced ECC

This paper presents test and numerical studies on the behaviours of basalt fibre textile and engineered cementitious composite (ECC) reinforced concrete-filled steel tube (CFST) columns under axial compression . A total of 17 specimens were subjected to axial compression, with variables including the number of basalt fibre layers, mesh size , steel tube thickness and concrete strength grade. The behaviours were analyzed through the failure patterns, load-vertical strain responses, and the confinement mechanism. Results indicated that textile-reinforced ECC (TR-ECC) enhanced the axial performance of CFST columns, with ultimate strength improvement ranging from 9 % to 22 %. Additionally, the ultimate strength improved with the increase in the steel tube thickness, the number of textile layers, and the concrete strength. A series of finite element (FE) models were then established and validated by comparing the load versus displacement curves with test data. Parametric studies were conducted to investigate the influence of the number of textile layer, textile grid size, material strength and steel ratio on the axial capacity . Results showed that an increase in mesh size leads to a decrease in the axial resistance of the strengthened columns. Finally, a simplified formula for calculating the axial capacity of the CFSTs reinforced with TR-ECC was developed. • Compression performance of CFSTs strengthened with BFRP textile and ECC. • Failure pattern, load-vertical strain response, and the confinement mechanism. • Effects of key parameters on the ultimate strength. • Simplified equations for calculating the compressive resistance.