The effective length of columns in multi-storey frames

摘要: Abstract Codes of practice rely on the effective length method to assess stability multi-storey frames. The involves isolating a critical column within frame and evaluating rotational translational stiffness its end restraints, so that buckling load may be obtained. non-contradictory complementary information (NCCI) document SN008a (Oppe et al., 2005) BS EN 1993-1 (BSI, provides erroneous results in certain situations because it omits contribution made restraints by columns above below, other same storey. Two improvements are proposed this paper. First, axial adjoining is incorporated into calculation length. Second, modification ratio allows adjacent considered. shown consistently provide 2% computed structural analysis software, as opposed up 80% discrepancies seen using NCCI 2005).