Experimental and finite element studies on the structural behavior of BFRC continuous beams reinforced with BFRP bars

Abstract

This study presents an experimental and numerical study on the structural behavior and moment redistribution of basalt fiber-reinforced concrete (BFRC) continuous beams with basalt fiber-reinforced polymer (BFRP) bars. A total of seven BFRP-BFRC two-span continuous beams were tested to failure under a five-point test setup. Three parameters were investigated: volume fractions (Vf) of basalt macro-fibers (BMF), BFRP reinforcement ratio, and stirrups spacing. Test results indicated that compared to stirrups spacing, reinforcement ratio and Vf of BMF were more significant in improving the structural performance and moment redistribution of the tested beams. Furthermore, nonlinear 2D finite element (FE) models were developed using the commercial ABAQUS software to predict the behavior of the tested beams. The FE analysis accounted for the tensile cracking and compressive crushing of concrete using the built-in concrete damaged plasticity model. Ayub's analytical model was employed to simulate the nonlinearity of BFRC in compression. The accuracy of the FE models was validated using the experimental load-deflection responses and crack patterns at failure. Good agreement was obtained between the experimental and numerical results with the experimental-to-predicted mean, standard deviation, and coefficient of variance values of 1.036, 0.041, and 3.95% for the ultimate loads and 0.993, 0.046, and 4.68% for the deflections, respectively.