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Reinforced Concrete Design II

Lecture 9

Dr. Nader Okasha

Biaxial Bending

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

The Bresler Equation

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Biaxial bending in columnsInteraction diagrams for biaxial bending

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Biaxial bending in columns

Design Procedure for biaxial bending:

A- Determine reinforcement based on the biaxial bending capacity:

1- Determine the dimensions based on a reasonable stress in the column.2- Determine in the week axis direction (any direction for square sections.3- Calculate the biaxial bending moment in the week axis direction.4- Use an interaction diagram to design the reinforcement for the section.

B- Use the Bresler equation to check the axial capacity of the section

1- Calculate Pnx from the interaction diagram assuming only Mnx is applied.2- Calculate Pny from the interaction diagram assuming only Mny is applied.3- Calculate P0.4- Calculate Pn and check un PP

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns

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Biaxial bending in columns