ABSTRACT
This chapter addresses shear polarisation of waves, modelling of active chiral media and dynamic response of discrete structured interfaces, which may exhibit shielding, negative refraction and focusing of elastic waves. It is based on the notion of an active gyro-lattice containing appropriately tuned spinners. The precession of gyroscopes leads to formation of vortex-like waveforms, which impacts upon the polarisation of elastic waves in such a structured medium. Structured interfaces may possess inertia, and tractions may become discontinuous across such interfaces in dynamic regimes. The derivation and analysis of dynamic transmission conditions for structured interfaces are important for the evaluation of transmission and reflection properties of heterogeneous composite media. The derivation and analysis of dynamic transmission conditions for structured interfaces are important for the evaluation of transmission and reflection properties of heterogeneous composite media. In addition, transmission resonances for elastic waves, as well as negative refraction and focusing are of great interest.
