Bending with or without axial force of prestressed structures: the methods for avoiding brittle failure and the strength fctx
Eurocode 2 part 2: Design of concrete bridge structures 6.1 (109)
The brittle failure of prestressed members, caused by failure of prestressing tendons, may be avoided by any of methods (a), (b) or (c). Cf. the standard for more details.
In the method (b), the recommended value of the tensile strength fctx for the calculation of the cracking bending moment is fctm, see Table 3.1.