The purpose of this document is to outline the steps to verify reinforced concrete column design using
the capacity curve, or commonly referred to as N-M (Axial-Moment) Interactive Diagram using Eurocode 2 and BS8110.

The N-M Interaction Diagram will be derived using empirical formulas of concrete stress block. This is
then compared to the same capacity curve generated by ProtaStructure column design, to verify the
validity and adequacy of its column design. In fact, this method can be used to check and verify the adequacy of any column design program, as
the capacity curve generated by any column design application should tally with the empirical curve as
it is derived from first principles.

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