A　novel　dual　lateral　force　resisting　system　consisting　of　low-yield　point　steel　plate　shear　walls　with　diagonal　T-shaped-stiffener　(LSPSW-DTS)　was　proposed　as　a　promising　alternative　to　improve　the　buckling　stability,　seismic　behavior,　and　serviceability　of　SPSWs.　The　influence　of　several　key　factors　on　the　cyclic　performance,　failure　behavior,　and　plate-frame　interaction　characteristics　was　evaluated　using　numerical　investigations.　The　optimum　configuration　of　stiffeners　was　determined　to　achieve　a　material-efficient　design.　The　critical　values　of　the　column　flexibility　coefficient　were　determined　to　ensure　sufficient　development　of　the　tension　fields　inside　the　infill　panel.　Finally,　the　contribution　of　the　boundary　frame　was　quantified　by　establishing　an　equation　for　predicting　the　proportional　shear　resistance　of　the　infill　panels.　The　analytical　results　demonstrated　that　the　hysteresis　curves,　shear　capacity,　and　energy　dissipation　of　all　the　overall　structure,　infill　panel,　and　boundary　frame　enhanced　as　the　flexural　stiffness　ratios　of　the　stiffeners　increased,　demonstrating　that　the　DTS　significantly　improved　both　the　cyclic　performance　of　LSPSW　structures　and　the　plate-frame　interaction.　In　addition,　the　plates　of　the　stiffeners　did　not　experience　adverse　local　instability,　indicating　the　advantages　of　the　T-shaped　stiffeners.　However,　once　the　flexural　stiffness　ratio　of　the　stiffeners　was　sufficiently　large,　an　additional　increase　in　the　degree　of　stiffening　had　only　minor　positive　effects　on　the　shear　capacity　and　energy　dissipation　performance.　A　larger　flexural　stiffness　ratio　was　required　for　larger　width-to-height　ratios,　height-to-thickness　ratios,　or　column　flexibility　coefficients　to　obtain　the　expected　failure　modes　and　achieve　satisfactory　shear　capacity　efficiency　and　energy　dissipation　efficiency.　(C)　2020　Elsevier　Ltd.　All　rights　reserved.