BUILDING AND LOADS
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Fig. 5.7 Floor beam—centre column joint: (a) joint arrangement; (b) beam endplate; (c) column flange.
5.5 BRACED RIGID PLASTIC DESIGN 5.5.1 Design procedure The plastic design method for non-sway frames is set out in Clause 5.7.2 of BS 5950. This clause specifies that the frame should have an effective bracing system independent of the bending stiffness of the frame members. The columns are to be checked for buckling resistance in accordance with Clause 4.8.3.3, Design of Compression Members with Moments. The above code provisions indicate the following. • Beams are designed for fixed end plastic moments— where W is the design load.
Mp=WL/16
• Columns are designed to provide sufficient resistance for plastic hinges to form in the beams. In pre-limit state terminology, they are designed to remain elastic.