The　steel　column　base　of　the　main　truss　structure　of　the　National　Stadium　is　anchored　in　reinforced　concrete　pile　cap,　where　the　stress　state　is　complex,　lacking　similar　experiments　in　literature.　Four　experimental　programs　were　carried　out　to　investigate　the　anchorage　performance　of　steel　column　bases.　Two　specimens　are　reinforced　with　pull-out　resistant　shear　bar　and　the　other　two　specimens　are　not.　Through　the　tests　on　the　anchorage　performance　of　steel　column　base　under　repeated　loads,　the　tested　ultimate　loads,　ductility　and　reasonable　modes　of　reinforcement　design　of　specimens　are　presented.　Test　results　reveal　that　the　ultimate　loads　and　ductility　of　the　specimens　with　pull-out　resistant　shear　bar　were　higher　than　those　of　the　specimens　without　pull-out　resistant　shear　bar.　Based　on　the　experimental　studies,　the　simplified　mechanical　model　is　proposed.　The　calculating　results　agree　well　with　the　experimental　results.