A pseudo-elastic material damage model, part II: Application to the scaling of specimen size, material behavior and loading rate

Abstract

The interpretation and utility of reduced scale testing requires an understanding of the factors which affect test specimen behavior. Specimen size, material toughness and load increment size influence the extent of nonlinear load-displacement response, material inhomogeneity within the specimen and the amount of stable crack growth. A consistent, rational methodology is presented from which reduced scale testing programs may be constructed and interpreted. A finite element simulation for each of twenty-seven uniaxial tensile specimens is used to illustrate the methodology. Cumulative material damage and stable crack growth are monitored using the strain energy density criterion. From the results of the simulation, the linear behavior of the strain energy density factor S with respect to crack length a is shown. The influence of size, material and rate are reduced to translations and rotations of the S versus a representation, producing a valuable tool for both design and analysis.