ABSTRACT
This chapter describes the protocol to compute the interaction parameter Gsc from experimental data. The experimental failure data come from ply—not laminate—regression equations developed at constant test frequencies and load ratio (R) ratios. The interaction parameter Gsc is computed for any ply and any loading by solving the unified equation fed with known experimental failure points. The known failure points derive from experimental regression equations determined for a few chosen R ratios and loading frequencies. The value of the interaction parameter Gsc to enter the unified equation is obtained by interpolation. The time-independent resin-dominated failures use a simplified version of the unified equation. The generation of good Gsc values requires many experimental regression equations developed at several R ratios and load frequencies. The lack of experimental regression equations limits the application of the unified equation in many practical situations involving fiber-dominated rupture.
