The　research　and　application　of　particle　damper　in　civil　engineering　is　simply　in　a　theoretical　and　experimental　stage　because　of　the　high　nonlinear　characteristics　and　complex　factors,　and　no　more　mature　and　reliable　theory　has　been　formed　to　guide　the　design　and　application　in　actual　civil　engineering.　When　the　damping　particles　are　not　accumulated,　considering　the　collision　process　and　friction　effect　between　particles　and　chamber,　a　mechanical　model　of　particle　damper-SDOF　system　is　constructed.　The　analytical　solution　of　the　displacement　response　of　the　theoretical　model　under　harmonic　excitation　is　obtained.　The　mechanical　model　could　fully　reflect　the　collision　and　non-collision　process　of　particle　dampers,　and　the　phase　trajectories　could　reflect　the　complex　nonlinear　characteristics　of　particle　dampers.　The　rationality　of　the　model　and　the　correctness　of　the　analytical　results　are　proved　by　the　verification　of　the　hypothesis　of　the　particle　damper　and　the　electromagnetic　shaking　table　test　of　a　single　steel　frame　under　simple　harmonic　excitation.　Finally,　the　parameters　of　the　particle　dampers　are　analyzed　in　terms　of　particle　size,　excitation　amplitude,　excitation　frequency　and　damping　particle　motion　gap.　Moreover,　compared　with　the　existing　model　of　impact　dampers,　the　results　show　that　the　mechanical　model　is　more　reasonable　for　evaluating　the　damping　performance　of　particle　damper.　©　2019,　Engineering　Mechanics　Press.　All　right　reserved.