This　study　developed　a　novel　prefabricated　self-centering　U-shaped　SMA-Steel　hybrid　plate　damper　(SMA-Steel-UD)　based　on　the　excellent　characteristics　of　SMA,　to　reduce　the　residual　deformation　of　the　conventional　U-shaped　Steel　plate　damper　under　severe　earthquakes.　The　developed　SMA-Steel-UD　consisted　of　U-shaped　SMA　plates　(SMA-Us)　and　U-shaped　steel　plates　(Steel-Us)　assembled　in　parallel,　and　its　working　principle　was　introduced　and　the　analytical　model　was　established.　Then,　the　mechanical　properties　of　SMA　plate　were　firstly　investigated　experimentally,　and　the　test　results　showed　that　the　SMA　plate　behaved　large　self-centering　capacity　and　great　deformability.　Subsequently,　the　quasi-static　cyclic　loading　tests　of　the　components　of　the　damper　including　U-shaped　SMA　plate　damper　(SMA-UD)　and　U-shaped　Steel　plate　damper　(Steel-UD)　and　the　whole　damper　were　carried　out　to　investigate　the　hysteretic　performance,　and　to　further　validate　the　established　analytical　model.　The　experimental　results　showed　that　the　SMA-Steel-UD　exhibited　satisfactory　flag-shape　hysteresis　behavior　with　excellent　self-centering　ability　and　stable　energy　dissipation　capacity,　and　owned　a　large　deformation　capacity.　Parametric　studies　were　further　performed　to　evaluate　the　influences　of　the　key　parameters　of　SMA-Steel-UD　on　the　hysteretic　performance.　To　ensure　the　excellent　self-centering　capacity　of　the　damper,　the　total　self-centering　force　of　the　U-shaped　SMA　plates　should　be　greater　than　the　total　yield　force　of　the　U-shaped　steel　plates.　©　2024