  We analyse an asymptotic low-dimensional model of anti-plane shear in a thin
bi-material strip containing a periodic array of interfacial cracks. Both ideal
and non-ideal interfaces are considered. We find that the previously derived
asymptotic models display a degree of inaccuracy in predicting standing wave
eigenfrequencies and suggest an improvement to the asymptotic model to address
this discrepancy. Computations demonstrate that the correction to the standing
wave eigenfrequencies greatly improve the accuracy of the low-dimensional
model.
