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Reinforcement in typical columns

Column with section 400x400mm

Column with section 500x500 mm

Column with section 600x400 mm

Column with section 900x250 mm

Column with a circular section D=500 mm

Column with ‘Γ’ section 450x450x250x250 mm

Column with ‘Γ’ section 400x800x250x250 mm

Column with ‘T’ section 700x500x250x250 mm

Column with quadrilateral section 600x500 mm

Column with ‘Z’ section 700x650x600x250x250x250 mm

Note:

Placing a rebar in the internal corner of composite sections (‘Γ’, ‘Ζ’ section etc) is optional be-cause:

a) it does not significantly enhance the flexural strength since it is not placed in a section’s cor-ner (based on the fact that tensile stresses appear to the external corners of the elements’ sec-tions)

b) it does not increase the confinement because in case of an intense earthquake, where con-crete spalling will occur, that rebar might buckle since it is not completely restrained.

c) however, in all cases this corner rebar may be constructionally used without its contribution to the section’s calculated requirement.


The internal rebar (in red), in a severe seismic event, might buckle (due to the bulking of stirrups) and therefore it will not contribute to the confinement.
The internal rebar (in red), in a severe seismic event, might buckle (due to the bulking of stirrups) and therefore it will not contribute to the confinement.

 


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