STAAD.Pro Help

D5.D.8.6 Clause – Modification factor, f, for LTB checks

STAAD.Pro uses the value of the modification factor f as per eqn 6.58 of PN-EN 1993-1-1. The correction factor, kc, will be evaluated as:

kc = √(CmLT)


  • CmLT is the equivalent uniform moment factor from table B.3 of PN-EN 1993-1-1. CmLT is evaluated based on the end conditions of the member and the shape of the bending moment diagram. However, if the KC parameter has been used, then the program will use the specified value.