  The paper presents new results on localisation and transmission of flexural
waves in a structured plate containing a semi-infinite two-dimensional array of
rigid pins. In particular, surface waves are identified and studied at the
interface boundary between the homogeneous part of the flexural plate and the
part occupied by rigid pins. A formal connection has been made with the
dispersion properties of flexural Bloch waves in an infinite doubly periodic
array of rigid pins. Special attention is given to regimes corresponding to
standing waves of different types as well as Dirac-like points, that may occur
on the dispersion surfaces. A single half-grating problem, hitherto unreported
in the literature, is also shown to bring interesting solutions.
