Coupled flexural-torsional vibration band gap in periodic beam including warping effect

The propagation of coupled flexural-torsional vibration in theperiodic beam including warping effect is investigated with thetransfer matrix theory. The band structures of the periodic beam,both including warping effect and ignoring warping effect, areobtained. The frequency response function of the finite periodicbeams is simulated with finite element method, which shows largevibration attenuation in the frequency range of the gap as expected.The effect of warping stiffness on the band structure is studied andit is concluded that substantial error can be produced in highfrequency range if the effect is ignored. The result includingwarping effect agrees quite well with the simulated result.