Size effect and strain rate effect on seismic behavior of reinforced concrete beam‐column joints

Abstract

AbstractThe mechanical behavior of reinforced concrete (RC) beam‐column joints with different sizes under cyclic loads at varying rates was investigated, aiming at attaining a better understanding of the size effect and strain rate effect on RC beam‐column joints. First, a 2D mesoscale numerical model was established and verified by existing experimental results. Second, numerical tests regarding seismic performances of RC beam‐column joints were carried out. A total of four structural sizes and five strain rates were taken into consideration. The damage patterns, hysteretic curves, skeleton curves, the displacement ductility, the stiffness degradation, and the shear deformation of joints under different working conditions were analyzed. Finally, the size effect and strain rate effect on shear resistance and shear failure mechanism of joints were discussed. In addition, a semitheoretical formula considering structural sizes and strain rates for shear strength calculation was proposed and verified by available experimental data.