A　displacement　dependent　nonlinear　damping　model　was　proposed　to　overcome　the　disadvantage　associated　with　the　current　damping　model,　e.g.　cannot　represent　the　relationship　between　damping　and　the　damage　characteristics　of　reinforced　concrete　(RC)　structure.　The　proposed　damping　model　incorporated　the　viscous　damping　energy　dissipation　and　the　internal　friction　energy　dissipation　related　to　structural　damage.　The　internal　friction　damping　was　decomposed　into　the　residual　stress　effect　and　the　bond　slip　effect.　The　identification　method　of　damping　parameters　of　the　model　was　presented　based　on　energy　conservation　principle,　and　the　numerical　simulation　was　carried　out.　Damage　loading　and　dynamic　test　of　a　RC　simply　supported　beam　was　carried　out,　and　the　damping　parameters　of　each　damage　state　were　identified　based　on　the　proposed　damping　model　and　the　corresponding　dynamic　model.　The　variation　regularity　and　the　intrinsic　relationship　between　the　nonlinear　damping　and　the　damage　were　analyzed.　The　results　showed　that　the　proposed　damping　model　not　only　is　able　to　characterize　the　fact　that　damping　ratio　increases　with　the　increase　of　the　displacement,　but　can　represents　the　evolution　behavior　of　damping　ratio　with　damage　degree.　©　2017,　Engineering　Mechanics　Press.　All　right　reserved.