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At the tensile face, the crack width is

For nonbonded beams, the factor 6.51 in Equations 5.102a and 5.102b becomes 6.83. The crack spacing stabilizes itself beyond an incremental stress Afs of 30,000 to 35,000 psi, depending on the total reinforcement percent pT of both prestressed and nonprestressed steels.

Recent work by Nawy et al. [13] on the cracking performance of high-strength prestressed concrete beams, both pretensioned and posttensioned, has shown that the factor 5.85 in Equation 8.101a is considerably reduced. For concrete strengths in the range of 9,000 to 14,000 psi (60 to 100 MPa), this factor reduces to 2.75, so that the expression for the maximum crack width at the reinforcement level (inch) becomes

In SI units, the expression is

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