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Hitesh
11th June 2009, 09:34 AM
It may be a naive question but what does the flag defaulted at 99% mean?

Tony Bryer
11th June 2009, 09:51 AM
The flag value triggers an on-screen warning if the bending stress, shear stress or deflection exceeds this percentage of the permissible value. Some designers take the view that if a beam is stressed to 99% of capacity this is the optimum choice (there is of course still a significant factor of safety provided by the relevant BS) whilst others like to have something in hand to cover changes of loading at a later date (e.g. contractor uses dense instead of lightweight blocks). If you set the flag percentage to (say) 90% and the selected member has a bending stress equal to 92% of the permissible value you will see an on-screen warning "bending stress exceeds 90% of permissible value" and in the Project Manager the description is prefaced with ???. The message does not appear on the printout as the selected member i within BS stress and deflection limits.