Study on axial compression properties of concrete columns wrapped with basalt textile-reinforced fine concrete (BTRC) jackets

Abstract

A total of 20 column specimens were prepared for axial compressive tests to investigate the compressive behavior of the concrete column (including plain concrete column and reinforced concrete column) and were wrapped with basalt textile-reinforced fine concrete (BTRC) jackets. Four parameters including the number of textile layers, stirrup spacing, core concrete strength, and the use of short fibers were considered and evaluated. The results indicate that the bearing capacity and the displacement ductility of the columns were clearly improved with an increase in the number of textile layers. For the BTRC-strengthened columns, as the number of textile layers increased from 0 to 2, 3, and 4, the bearing capacity increased by 33.2%, 39.0%, and 46.9%, respectively. Moreover, the improvement in the bearing capacity and deformation energy was affected by core concrete strength. Columns with lower concrete strength obtained a more effective increment. Additionally, short fibers also played an important role in improving the compressive behavior of the columns. Finally, the available experimental data on BTRC-confined concrete columns was compiled, and an analytical model was proposed based on the test results in this study and other studies to predict the stress-strain relationship of BTRC-confined concrete under axial compressive load. The stress-strain curves of BTRC-confined concrete predicted by the analytical model agreed strongly with the experimental curves, proving the model proposed in this study can be used to predict the stress-strain relationship of BTRC-confined concrete.