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A pretensioned concrete beam 200mm wide and 300mm deep, is prestressed by straight wires carrying an initial force of 150kn at eccentricity of 50mm, area of steel wires is 188mm2. Find initial stress in steel?

A pretensioned concrete beam 200mm wide and 300mm deep, is prestressed by straight wires carrying an initial force of 150kn at eccentricity of 50mm, area of steel wires is 188mm2. Find initial stress in steel? Correct Answer 800

b = 200mm, d = 300mm, p = 150kn = 150×103, e = 50mm, a = 188n/mm2, Initial stress in steel = (150×103/188) = 800n/mm2.

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