Flexural behavior of carbon fiber-reinforced concrete beams under impact loading

The flexural behavior of carbon fiber-reinforced concrete (CFRC) beams under impact loading was studied herein. A modified molding process was proposed for manufacturing CFRC beams to achieve the uniform dispersion of 20-mm long carbon fibers in the concrete matrix. Different fiber volume fractions and impact velocities were considered. Their effects on the tensile and compressive strain, distribution of vertical displacement and acceleration, energy absorption, and dynamic increase factor (DIF) were analyzed to investigate the mechanical properties. The results indicated that the CFRC beams with 0.35% fiber content absorbed the highest energy (about 2.3 times that of beams without fibers). Based on the approximate linear distribution of inertial force along CFRC beams, an equation was deduced to calculate the generalized inertial force. The results indicated that the DIF increased with strain rate, and an empirical equation was proposed to describe the strain rate effect.

Automated summary

This study investigated the flexural behavior of carbon fiber-reinforced concrete (CFRC) beams under impact loading, analyzing the effects of different fiber volume fractions and impact velocities on mechanical properties. It was found that CFRC beams with 0.35% fiber content absorbed the highest energy, and an equation was deduced to calculate the generalized inertial force based on linear distribution of inertial force along CFRC beams. The results also showed that the dynamic increase factor (DIF) increased with strain rate, and an empirical equation was proposed to describe the strain rate effect.