INNOCENT SYLVIA
16CA021152
ARC 425 ASSIGNMENT
QUESTION:
1. Explain section classification in structural steel beam design;
ANSWER:
In Class 1 cross sections are those which can form a plastic hinge with the rotation capacity for
plastic analysis.
Plastic hinge develops in beams when the cross section has become plastic
If plastic design method is used in the structural analysis, all members must be this type
Class 2 cross sections are those which can develop their plastic moment resistance, but have
limited rotation capacity.
Class 3 cross sections are those in which the calculated stress in the extreme compression fiber
of the steel member can reach its yield strength, but local buckling is liable to prevent
development of the plastic moment resistance.
Class 4 cross sections are those in which it is necessary to make explicit allowances for the
effects of local buckling when determining their moment resistance or compression resistance.
16CA021152
ARC 425 ASSIGNMENT
QUESTION:
1. Explain section classification in structural steel beam design;
ANSWER:
In Class 1 cross sections are those which can form a plastic hinge with the rotation capacity for
plastic analysis.
Plastic hinge develops in beams when the cross section has become plastic
If plastic design method is used in the structural analysis, all members must be this type
Class 2 cross sections are those which can develop their plastic moment resistance, but have
limited rotation capacity.
Class 3 cross sections are those in which the calculated stress in the extreme compression fiber
of the steel member can reach its yield strength, but local buckling is liable to prevent
development of the plastic moment resistance.
Class 4 cross sections are those in which it is necessary to make explicit allowances for the
effects of local buckling when determining their moment resistance or compression resistance.
