In　the　experiment　of　scaled　models　to　dealing　with　the　impact　of　reinforced　concrete　large　structures,　the　strain　rate　hardening　effect　can　lead　to　significant　differences　between　the　dynamic　responses　of　prototype　and　model.　In　the　present　study,　this　thorny　problem　is　solved　by　adjusting　the　impact　velocity.　Based　on　the　mechanisms　of　different　dynamic　responses,　the　similarity　laws　for　the　global　and　local　responses　of　reinforced　concrete　beams　subjected　to　impact　loading　are　proposed　by　considering　the　strain-rate　effect　of　materials　through　Buckingham　Pi-theorem,　where　constitutive　models　of　different　materials　are　employed　for　inferring　dynamic　stress.　In　dimensional　analysis,　multiple　control　factors　need　to　be　considered　simultaneously,　such　as　the　strain-rate　effects　of　steel　and　concrete,　since　reinforced　concrete　components　are　typical　composite　structures.　The　similarity　law　cannot　be　unified　when　considering　multiple　control　factors.　In　view　of　this,　it　is　recommended　to　estimate　the　dynamic　response　of　reinforced　concrete　components　subjected　to　impact　loading　through　the　upper　and　lower　bounds　of　similarity　law.　The　upper　bound　of　similarity　law　is　based　on　the　strain-rate　effect　of　concrete,　while　the　lower　bound　of　similarity　law　is　based　on　the　strain-rate　effect　of　steel　bar.　The　numerical　models　of　reinforced　concrete　beams　are　established　based　on　the　experimental　background.　The　numerical　simulations　with　different　scaling　factors　indicate　that　the　model　modified　by　the　lower　bound　of　similarity　law　can　better　predict　the　global　response　of　prototype,　while　the　model　modified　by　the　upper　bound　of　similarity　law　can　more　accurately　predict　the　local　response　of　prototype.　In　addition,　the　influence　of　dynamic　elastic　modulus　of　reinforced　concrete　on　the　similarity　law　is　discussed　through　comparative　analysis.