A　new　type　of　damper　called　metal　alloy　brace　with　plump　hysteresis　loops　and　strong　dissipation　energy　capability　is　recommended.　Within　the　designed　displacement　the　output　force　is　stable　and　small,　while　the　output　force　can　increase　greatly　when　the　designed　displacement　is　exceeded.　The　FE　model　of　a　viaduct　has　been　established　to　analyze　the　implication　of　the　metal　alloy　brace　on　seismic　control　and　make　comparison　with　the　traditional　restrainers.　The　results　show　that　the　damper　can　provide　more　than　40　percent　of　passive　energy　dissipation　ratio　under　the　seismic　excitation　of　design　intensity,　which　can　inhibit　the　elastic　hinge　and　restrain　the　bearing　displacement.　When　the　designed　intensity　rises,　the　metal　alloy　brace　can　protect　the　bridge　not　only　by　dissipating　energy,　but　also　by　restraining　the　displacement　to　avoid　girder＇s　falling　and　collision.　Restrainers　can　also　effectively　prevent　the　falling-off　of　the　girder,　but　may　enlarge　the　shear　force　at　the　piers　and　fixed　bearings.　So　the　metal　alloy　brace　can　replace　the　restrainers　because　it　can　ultimately　protect　each　component　of　the　bridge　from　destroying.