Moment capacity method
This calculation method allows the designer the opportunity to assess the fire resistance of a beam by calculating its moment capacity using the temperature profile at the required fire resistance time.
If the applied moment is less than the moment capacity of the beam the member is deemed to have adequate fire resistance without fire protection.
The method is only applicable for beams with webs which satisfy the requirements for a plastic or compact section as defined in BS5950 Part 1. It is best suited for use with shelf angle floor beams. Appendix E of BS5950 Part 8 gives all the information required to calculate the moment capacity of shelf angle floor beams at 30, 60 and 90 minutes and a more detailed treatment is given in the appropriate Steel Construction Institute publication.
Construction Services and Development
PO Box 1
Brigg Road
Scunthorpe
North Lincolnshire DN16 1BP
United Kingdom
T +44 (0) 1724 405060
F +44 (0) 1724 404224
