Effect of Initial Static Loadings on Dynamic Shear Performance of BFRP-Reinforced Concrete Deep Beams

Abstract

To better understand the effect of initial static loading on the dynamic shear performance of concrete deep beams reinforced with basalt fiber–reinforced polymer (BFRP) bars, a three-dimensional mesoscale numerical model was established considering the strain rate effect of each material and the interaction between concrete and BFRP bars. The effect of the initial static loading on the damage evolution and failure mechanism of the concrete deep beams (shear span ratio λ = 1.0) reinforced with BFRP bars (BFRP-RC deep beams) with different stirrup ratios was analyzed. The results prove that: (1) the shear capacity, failure mode, and deformation capacity of BFRP-RC deep beams have a strain rate effect, that is, the shear capacity, deformation capacity, and damage degree of beams increase with the increase of strain rate; (2) the increase of strain rate and stirrup ratio can improve the shear capacity and deformation capacity of beams, while the strain rate plays the leading role; and (3) the shear capacity, deformation capacity, and damage degree of BFRP-reinforced concrete deep beam decrease as the initial static loading increases under different strain rates. However, the increase in strain rate will weaken the effect of initial static loading on the dynamic performance of the beams.