The　reliable　one-sided　bolts　constitute　a　vital　component　of　fully　bolted　joints　in　demountable　steel　structures.　In　this　study,　an　innovative　triangular　headed　one-sided　bolt　(THOB)　based　on　the　traditional　hexagon　headed　bolt　(HHB)　was　proposed,　and　the　tensile　performance　of　T-stubs　using　the　THOBs　has　been　investigated　through　experimental　and　numerical　approaches.　Monotonic　tensile　tests　were　performed　on　25　THOB　bolted　T-stubs　to　analyze　the　failure　modes　and　load-carrying　performance　of　the　specimens.　The　test　results　disclosed　that,　beyond　the　three　typical　failure　modes　stipulated　in　the　Eurocode　3,　the　specimens　exhibited　a　characteristic　failure　mode,　namely,　limit　groove　pull-off　failure.　Finite　element　models,　validated　by　the　test　results,　were　employed　for　the　parametric　analysis　to　compare　the　load-carrying　performance　of　THOB　bolted　T-stubs　with　that　of　HHB　bolted　T-stubs.　The　finite　element　analysis　results　indicated　that　the　average　ratio　of　the　plastic　load-carrying　capacity　of　THOB　bolted　T-stubs　to　HHB　bolted　T-stubs　was　close　to　0.88.　Furthermore,　the　load-carrying　capacity　of　THOB　bolted　T-stubs　was　evaluated　using　existing　specifications　for　comparison　with　the　experimental　and　numerical　results,　and　Eurocode　3　calculations　for　the　plastic　load-carrying　capacities　of　THOB　bolted　T-stubs　demonstrated　a　commendable　level　of　precision.　Finally　design　recommendations　were　put　forward　based　on　the　test　and　finite　element　analysis　results.　©　2024　Institution　of　Structural　Engineers