EFFECTIVE LENGTH FACTOR FOR THE BASE-FIXED COLUMN FOR PORTAL FRAMES WITH CRANE LOADS

Because of the crane loads, columns in portal frames are stepped.The effective length of the stepped columns is not available either from the specifications or from the literature, when the column base is fixed.This paper analyses the buckling of hinged portal frame with crane loads.Formulas and tables of the effective length factors for the base-fixed column both in plane and out of plane are proposed.The results from the proposed method are in good agreement with those of FEM,based on which the formulas of the effective length factors are also simplified.