Derivation of a simplified stress–crack width law for Fiber Reinforced Concrete through a revised round panel test

The round determinate panel (RDP), according to ASTM, was found to be a reliable, consistent and repeatable test method for the measurement of the energy absorption in Fiber Reinforced Concrete (FRC) composites. A smaller panel was proposed and experimentally investigated by the authors in previous scientific contributions.
An analytical approach is herein reported toward the definition of a simplified stress-crack width law for FRC, determined from tests on small panels according to the requirements of Model Code 2010 for tension softening materials. To this aim, the measurement of the three crack widths was implemented in the test procedure and, in addition, a kinematic approach was proposed to predict the crack width of panels.