Test parameters for evaluating toughness of glass-fiber reinforced concrete panels

This study describes the ability of different test methods to measure the toughness of glass-fiber reinforced concrete (GFRC) composites. The three loading configurations used were: uniaxial tensile, third-point flexural, and instrumented impact. Fracture was observed to be dependent on the specimen geometry; loading geometry; gage length used; strain rate; and the extent of accelerated aging. Assuming that the local tensile stress-strain response can be expressed in the form of a bilinear ascending portion and an exponentially descending portion, both gage-length effects and loading geometry effects can be predicted. Using the analytical tensile stress-strain response, the experimentally observed flexural load-deflection and toughness were predicted.