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Maximum strain at the extreme concrete compression fiber is assumed equal to 0.003.
Tensile strength of concrete is neglected.
The relationship between concrete compressive stress and strain is represented by equivalent rectangular concrete stress distribution method.
Concrete stress of 0.85fc' is assumed uniformly distributed over. Equivalent rectangular concrete stress zone bounded by edges of the cross section and a line parallel to the neutral axis located a distance α from the fiber of maximum compressive strain, as calculated by:
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$$ α = β_1c $$
"$$ E = mc^2 $$"
The distance between the fiber of maximum compressive stress and the neutral axis, c, is perpendicular to the neutral axis.
The value of β1 is determined using Codes.
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