State-of-the-Art Review on Concrete Softening Curve
The cohesive crack model is widely employed to the fracture analysis of concrete for mode I crack. The tension softening relationship is a very important constitutive law in the cohesive crack model. The determination methods of tension softening relationship of concrete are introduced in this paper which are direct tension methods, J-integral method and inverse analysis method. Meanwhile, those simplified softening curves including linear form and nonlinear form are summarized.
Z. F. Zhao et al., "State-of-the-Art Review on Concrete Softening Curve", Advanced Materials Research, Vols. 168-170, pp. 669-673, 2011