Five　frame　joints　strengthened　by　self-compacting　concrete　and　one　integral　casting　joint　for　comparison　were　prepared.　Static　tests　using　MTS　servo　loading　system　were　carried　out　to　these　joints　under　secondary　loads　to　study　the　influence　of　4　different　interface　treatments　on　the　seismic　performance.　Interface　treatments　of　the　five　strengthened　specimens　were　chiseling-grossness,　cutting　groove　with　different　groove　density,　combination　of　chiseling　and　cutting　groove,　and　combination　of　chiseling　and　planting　short　reinforced　bars　The　results　of　damage　process,　strains　of　both　the　old　steel　and　new　steel　and　the　load-displacement　hysteresis　loops　were　obtained.　It　is　found　that　all　the　four　interface　treatments　can　improve　the　co-operational　performance　of　the　old　concrete　and　new　concrete,　and　the　ultimate　strength,　displacement　and　displacement　ductility　coefficient　of　the　strengthened　joints　by　the　combination　of　chiseling　and　cutting　groove　or　the　combination　of　chiseling　and　planting　short　reinforced　bars　are　larger　than　those　by　chiseling　only,　and　as　for　the　ultimate　capacity,　the　strengthened　joints　with　each　of　the　4　treatments　was　close　to　the　integral　contrast　casting　joint.