FRACTURE PROCESS ZONE IN DYNAMICALLY LOADED CRACK-LINE WEDGE-LOADED, DOUBLE-CANTILEVER BEAM CONCRETE SPECIMENS

This reports results of tests on crack-line wedge-loaded, double cantiliver beam concrete specimens loaded to failure at increasing strain rates using a displacement controlled MTS dynamic-loading system. Linear elastic fracture mechanics (LEFM), together with a trailing fracture-process zone (FPZ) was used to evaluate the dynamic fracture response of those specimens. While the constitutive relations governing the FPZ was found to be strain-rate independent, the dynamic stress intensity factor was found to be strain-rate dependent. The energy release rate closely approximated the energy-dissipation rate in the FPZ, demonstrating that the FPZ is the dominant energy-dissipation mechanism in concrete.