Increasingly　heavy　urban　traffic　exacerbates　vehicle　impacts　on　reinforced　concrete　(RC)　bridge　columns,　possibly　leading　to　shear　failure　and　structural　collapse.　To　enhance　the　dynamic　shear　resistance　of　these　columns,　fiber　reinforced　polymers　(FRPs)　made　from　recycled　polyethylene　terephthalate　(PET)　plastic　bottles　were　used　for　external　strengthening.　PET　FRPs　offer　an　eco-friendly　alternative　by　repurposing　plastic　waste,　reducing　pollution,　and　promoting　circular　economy.　This　study　focused　on　the　dynamic　shear　responses　of　RC　columns　strengthened　with　PET　FRPs.　The　influences　of　FRP　types　and　number　of　FRP　layers　were　experimentally　revealed　in　terms　of　the　failure　modes,　impact　force,　reaction　force,　shear　force　and　impact　force-displacement　relationship.　It　was　found　that　significant　shear　damage　occurred　in　RC　columns　under　horizontal　impact　loads,　with　carbon　FRPs　(CFRPs)　strengthening　unable　to　alter　the　failure　mode.　Nevertheless,　the　use　of　PET　FRPs　transformed　the　failure　mode　to　a　flexural-shear　mode,　significantly　reducing　the　impact　duration,　maximum　and　residual　displacements,　and　energy　dissipation.　Moreover,　a　finite　element　model　was　validated　to　describe　the　impact　resistance　of　PET　FRP-strengthened　RC　columns,　as　supported　by　experimental　data.　A　parametric　study　further　investigated　the　effects　of　impact　velocity,　impact　mass,　number　of　FRP　layers,　and　reinforcement　ratios　on　the　dynamic　shear　responses.　Based　on　the　truss-arch　model,　a　dynamic　shear　strength　model　was　proposed　and　can　well　predict　the　dynamic　shear　capacity　of　FRP-strengthened　RC　circular　columns.　©　2025