A laminate of undisclosed configuration subjected to undisclosed load has a reported first ply failure (FPF) strength ratio R = 0.5. Note: the material, laminate stacking sequence, and the loads are not known.
(a) How much does the load need to be increased/decreased to avoid first ply failure, assuming all components are increased/decreased proportionally?
(b) or, How much does the thickness of the laminate need to be increased/decreased to avoid first ply failure, assuming all laminae thicknesses are increased/decreased proportionally?
(c) or, How much does the strength of the material need to be increased/decreased to avoid first ply failure, assuming all strength components are increased/decreased proportionally?