To evaluate the ultimate load of composite columns " steel – concrete "
having square or circular steel tubes filled hollow section with concrete
and Longitudinal reinforcing steel bars and subjected to centrical load and
Exposed to the standard f
ire in accordance with ISO 834 curve along and
from all sides,Fire duration ,buckling length of the column , geometrical
and mechanical properties of each material for structural and reinforcing
steels and concrete were in the base of the method, given in the French
National Annex of EN 1994-1-2.
