ACI: As recommended in the ACI 435R95 report (section 4.3.3),Software has reduced the SAFE uses a default modulus-of-rupture value from 7.5√f 'c to 4√f 'c. This change has been documented as Incident # 19168 in the
Release Notes.
Through manual overwrite, users are welcome to comply with the previous 7.5√f 'c value, or apply another value of 4√f 'c. PSI
For British, Hong Kong, Indian and Singapore Standards: Default modulus of rupture for cracked deflection is limited to 1 MPa or 0.55 MPa in short term and in long term deflection calculations, respectively.
For Australian and New Zealand codes: fr= 0.36√f 'c MPa
For Canadian code: fr= 0.3√f 'c MPa
For Euro-code:
Through manual overwrite by checking radio button of User Specified, users can comply with any other value based on engineering judgment or project requirements. This is done by selecting Run > Cracking Analysis > Cracking Modulus of Rupture > User Specified, Define > Materials... > Modify/Show Material... as shown in Figure 1:
Figure 1 - Overwrite modulus of rupture