Biaxial bending interaction diagrams

Biaxial bending interaction diagrams for reinforced concrete column design

solution

The steps to calculate biaxial flexural strength of a rectangular reinforced concrete column for a given nominal axial strength and moment ratio of biaxial bending moments are as follows:

1. assuming a value for the angle of the neutral axis (a) and the neutral axis depth (c) to calculate the strain values in each reinforcement layer

2. Calculate the forces values in the concrete (Cc) and reinforcement layers (Fst)

3. Calculate Pn, Mnx/Mny using the following equations


the procedure above should be repeated until the calculated Pn, and Mnx / Mny are euqal to the given Pn, and Mnx/Mny.

The following figure demonstrates the procedure explained above:

출처: Biaxial Bending Interaction Diagrams for Rectangular Reinforced Concrete Column Design (ACI 318-19) Structure Point






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Temperature effects_maturity

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