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The design of a reinforced concrete beam is said to be balanced if the maximum stresses in the steel and concrete are equal, respectively, to the allowable stresses σs and σc.. Show that to achieve a balanced design the distance x from the top of the beam to the neutral axis must be
Where Ec and Es are the moduli of elasticity of concrete and steel, respectively, and d is the distance from the top of the beam to the reinforcing steel.
Fig. P4.53 and P4.54
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