Experimental research on blast-resistance of one-way concrete slabs reinforced by BFRP bars under close-in explosion

Avoiding steel-bar-like corrosion in concrete members, basalt fiber reinforced plastic (BFRP) bars behaving as reinforcement have advantages in coastal civil engineering. One-way concrete slabs reinforced by BFRP bars (SRBBs) were designed to investigate their mechanical responses under static loads and explosions. High strength but relatively low stiffness of BFRP bars make SRBBs have different responses to slabs reinforced by steel bars (SRSBs). BFRP bars work in the elastic stage while steel bars result into plastic deformation after limited elastic deformation. SRBBs have larger deflections but higher ultimate loads compared with SRSBs in static bending tests. Explosive experiments reveal the damage patterns of SRBBs under various scaled distances, from 0.474 m/kg1/3 to 0.684 m/kg1/3. Crack, spall and breach are three typical damage modes for blast-loaded slabs. Compared with SRSB, the SRBB of the same reinforcement ratio and under the same scaled distance has larger deflections, but smaller damage level and greater residual loads. It is indicated that although the SRBB is not stiffer than the SRSB, it has greater anti-blast ability in current research.