Journal of engineering mechanics-asce vol:120 issue:10 pages:2013-2027
Nonlocal continuum damage mechanics and random field theory are used to model the stochastic damage behavior of a strain-softening material with random field properties, The randomness in the damage process is introduced by considering the initial damage threshold and the local strain-softening behavior as a bivariate random Nataf field, defined by the marginal distributions and correlation matrix. A key component of the model is the introduction of two different length parameters: the characteristic length of the nonlocal damage model and the correlation distance for the random field. The probabilistic nonlocal damage model is illustrated by presenting finite-element analyses of direct-tension tests. It is found that the specimen exhibits a structural behavior representing a nonsymmetrical deformation and nonlinear stress-displacement curve. The influence of the crosscorrelation coefficient between the initial damage and the strain-softening behavior is discussed. The probabilistic nonlocal damage model is also capable of describing the deterministic and probabilistic size effect of structures.