The　excellent　mechanical　properties　of　concrete-filled　steel　tube　(CFST)　make　it　a　competitive　alternative　to　column-cap/foundation　cap　socket　connections　in　accelerated　bridge　construction　(ABC).　To　investigate　more　research　parameters　and　facilitate　the　seismic　design　of　socket　CFST　column　joints,　a　detailed　numerical　analysis　model　of　socket　column-cap　beam　joint　was　established　and　verified　by　experimental　data,　and　the　bearing　capacity　and　failure　modes　of　socket　joints　under　the　dimensions　of　the　CFST　parts　and　their　material　properties　were　investigated　as　well.　It　is　found　that　the　size　of　steel　tube,　the　strength　of　steel　tube,　the　socket　depth　of　CFST,　and　the　type　of　forming　hole　have　significant　effects　on　the　strength　and　failure　modes　of　column　to　cap　beam　socket　joints.　This　study　also　proposed　a　moment　calculation　method　for　socket　joints　that　can　accurately　predicts　the　bearing　capacity　under　different　failure　modes.　Finally,　a　design　process　was　developed　to　facilitate　the　widespread　application　of　this　socket　CFST　column-cap　beam　joint　with　Ultra　High-Performance　Concrete　(UHPC)　grouted　connection.