1986 年 368 巻 p. 11-17
Since the localization and concentration of damage gives rise to the tensile fracture of concrete, the applicability of cohesive force model is noticed for the study on fracture mechanics of concrete. Then it requires further investigations for setting up the constitutive relation in the local fracture process zone. In this study a numerical analysis using an equivalent Dugdale model as giving the same J-integral value for any constitutive relation in which the cohesive force is introduced as a function of crack opening displacement was suggested and the fracture toughness of concrete was indirectly estimated by means of its reverse solution.