Strength of beam-columns in flexibly connected steel frames.

This thesis describes an experimental study undertaken to
examine the influence of joint resistance to in-plane moments on the
performance of steel columns and complete frames. The principal
objective of the tests was to provide experimental data against Which
sophisticated computer analysis programs may be verified.
Details of the experimental study of 22 joint tests, eight
column subassemblages, and two three storey, two bay steel frames are
reported. It is demonstrated that all beam to column connections have
an inherent degree of stiffness and that their moment-rotation
characteristics are non-linear. The load carrying capacity of
columns, confined to buckle in-plane, is shown to be enhanced considerably by the resistance to rotation provided by simple beam to column
connections. In frames incorporating flange cleat connections the
beams and columns can sustain greater loading and deflect less than is
predicted by current design models. The assumptions of pin-ended
columns and simply supported beams are shown to be conservative.
Comparisons of the results of the column and frame tests with
two finite element analysis programs are presented. The use of
computer programs for semi-rigid design as well as the development of
a simple approach are discussed.