Is creep a degradation phenomenon?

The evaluation and interpretation of time-dependent tensile stress-strain behavior (tension creep) of geosynthetics, used in reinforcement applications, under sustained loading has been of great significance, not only to the manufacturing industry, but also to the design community. The single largest reduction factor that must be considered in determination of a product design strength will be the creep reduction factor. However, is this degradation, or another physical behavior that must be accounted for in design strength calculations? This question takes on importance when reinforced structures are designed for seismic induced forces. What material strength is available to resist these short duration loads?