Scaling Effects in Composite Elastogranular Materials

Composite elastogranular materials combine the characteristics of their constituents, resulting in interesting and distinct mechanical properties. In this study, the effect of scale on the mechanical properties of composite string-rock materials comprised of elastic fibers embedded in a granular rock matrix is investigated. An experimental study is carried out to explore whether the relative global size of a composite elastogranular medium affects its bulk mechanical properties. In particular, the stiffness, strength and ratcheting-like behavior of string-rock composite is investigated for a cylindrical form. The stiffness of composite string-rock columns is shown to be scale-independent while the strength and compaction are observed to be driven by the scale.