Anomalous deflecting of SH0 wave by elastic metasurface in solids with phase discontinuities

The fundamental shear horizontal (SH0) wave in plate-like structures, which is a kind of non-dispersive wave, has recently drawn much attention as the big prospect in structural damage detection. In order to realize directional path detection to improve the flexibility of detection, an elastic metasurface is proposed to abnormally deflect incident SH0 waves in a plate. The metasurface is composed of different waveguides, which are designed with two kinds of solid materials. The normally incident SH0 wave impinges on an array of waveguides in the metasurface and couples with the S0 Lamb waves in waveguides; S0 Lamb waves then transmit through the waveguide array into transmitted plate producing the transmitted SH0 wave. Different waveguide length results in the phase shift. Based on the generalized Snell's law, the metasurface is theoretically designed. Then, the ability of deflecting SH0 waves is verified by the corresponding numerical simulation. The current study can provide a new degree of freedom for directional path detection based on SH0 guided wave.