Estimate the transmission length at the ends of a pretensioned beam prestressed by 7mm diameter wires. Assume the cube strength of concrete at transfer as 42n/mm2 (adopt empirical method)?

Estimate the transmission length at the ends of a pretensioned beam prestressed by 7mm diameter wires. Assume the cube strength of concrete at transfer as 42n/mm2 (adopt empirical method)? Correct Answer 610mm

Lt = ((fcu)1/2 x 103/β)1/2 = Transmission length, 7mm diameter smooth wires, β = 0.0174, fcu = 42n/mm2, Lt = ((42)1/2 x 103/ 0.0174) = 610mm = 87ϕ.
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