As recommended in the ACI 435R95 report, CSI Software has reduced the default modulus of rupture value from 7.5√f'c to 4√f'c. This change has been documented in the CSI Release Notes as Incident # 19168.
Users are welcome to comply with the previous 7.5√f'c value, or apply another value based on engineering judgment or project requirements, through manual overwrite. This is done using the ‘User Specified’ ‘Cracking Modulus of Rupture’ option under the ‘Run’ > ‘Cracking Analysis’ menu, as shown in Figure 1: