A　kind　of　modularized　prefabricated　steel　frame　with　through　column　and　solid-web　beam　is　presented.　Global　stability　of　beams　with　dual-channel　combined　section　formed　through　the　assembly　of　plates　is　studied.　Firstly,　the　feasibility　of　establishment　method　of　the　finite　element　model　is　proved.　Then　the　effect　of　bolt　pitch　on　the　static　performance　of　beams　with　dual-channel　combined　section　under　different　bolt　arrangement　is　analyzed　and　reasonable　bolt　pitch　is　investigated.　The　influence　of　beam　section　height,　flange　width　and　thickness,　web　thickness,　beam　length,　width　between　double　channels,　bolt　arrangement　and　load　type　on　the　global　stability　of　steel　beams　is　analyzed.　The　formula　for　calculating　the　equivalent　bending　moment　coefficient　and　the　relationship　between　the　elastic-plastic　stability　coefficient　and　the　elastic　stability　coefficient　are　obtained　by　the　fitting　method.　The　formula　for　calculating　the　elastic-plastic　stability　coefficient　under　different　load　types　are　obtained　through　the　equivalent　bending　moment　coefficient　and　elastic-plastic　correction　of　calculation　formula　of　elastic　stability　coefficient　under　pure　moment.　©　2018,　Engineering　Mechanics　Press.　All　right　reserved.