Detailed formation mechanisms of vibration band gaps in locally resonant periodic structures are investigated based on a two-dimensional locally resonant periodic structure. Firstly
based on the dynamic theory a basic theoretical hypothesis of the formation mechanism for the band gap of locally resonant periodic structure is proposed following the modal superposition principle. Secondly
the detailed formation mechanism of vibration band gaps is further clarified according to the formation mechanism model of band gaps. Finally
the formation mechanism of vibration band gaps is verified by the interaction between the elastic wave and the structure during the formation of vibration band gaps in a typical two-dimensional locally resonant periodic structure. The result shows that there exist six types of generalized propagation modes of waves in the locally resonant periodic structure
while these generalized propagation modes are formed by the mutual transformation of the main modes and these main modes are generated by corresponding 12 modes based on the superposition principle. The vibration mode dominated by the main mode of the vibrator determines the formation of a vibration band gap by suppressing or releasing the generalized propagation mode. When the oscillator's main mode suppresses the generalized propagation mode of the wave
a generalized sub-band gap that can only suppress the corresponding propagation mode is formed. The influencing mechanism of the band gap is further studied and an active design method of the band gap is proposed. This research may perfect the basic theory of periodic structure
lay a theoretical foundation for the study of band gap theory of periodic structure and the active design of band gap characteristics
and provide a new method for vibration reduction of engineering structures.
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BILLINGS L. Exotic optics: metamaterial world [J]. Nature, 2013, 500(7461): 138.
WU Jiuhui, MA Fuyin, ZHANG Siwen, et al. Application of acoustic metamaterials in low-frequency vibration and noise reduction [J]. Journal of Mechanical Engineering, 2016, 52(13): 69-78.
SIGALAS M, ECONOMOU E N. Band structure of elastic waves in two dimensional systems [J]. Solid State Communications, 1993, 86(3): 141-143.
LIU Z Y, ZHANG X X, MAO Y W, et al. Locally resonant sonic materials [J]. Science, 2000, 289: 201-205.
HO K M, CHENG C K, YANG Z, et al. Broadband locally resonant sonic shields [J]. Applied Physics Letters, 2003, 83(26): 5566-5568.
WU T T, HUANH Z G, TSAI T C, et al. Evidence of complete band gap and resonances in a plate with periodic stubbed surface [J]. Applied Physics Letters, 2008, 93(11): 111902.
HSU J. Local resonances-induced low-frequency band gaps in two-dimensional phononic crystals slabs with periodic stepped resonators [J]. Journal of Physics: D Applied Physics, 2011, 44(5): 055401.
ASSOUAR M B, OUDICH M. Enlargement of a locally resonant sonic band gap by using double-sides stubbed plate [J]. Applied Physics Letters, 2012, 100(12): 100123506.
LIF M, WANGY Z. Elastic wave propagation and localization in band gap materials: a review [J]. Science China, 2012, 55(10): 1734-1746.
CHEN Jiujiu, HAN Xu, LI Guangyao. Asymmetric lamb wave propagation in phononic crystal slabs with graded grating [J]. Journal of Applied Physics, 2013, 113(18): 184506.
GAO Ming, WU Zhiqiang. Band gap design for one-dimensional periodic structure with three oscillators [J]. Acta Physica Sinica, 2013, 62(14): 140507.
LI S B, CHEN T N, WANG X P, et al. Expansion of lower-frequency locally resonant band gaps using a double-sided stubbed composite phononic crystals plate with composite stubs [J]. Physics Letters: A, 2016, 380(25/26): 2167-2172.
LI Suobin, CHEN Tianning, XI Yanhui, et al. Forming mechanisms of low frequency complete band gaps in phononic crystal plate [J]. Journal of Xi'an Jiaotong University, 2016, 50(12): 51-57.
LI S B, XI Y H, CHEN T N, et al. Modulating Lamb wave band gaps using an elastic metamaterial plate [J]. Acoustic Journal, 2017, 63(5): 508-516.
XU Qing,ZHANG Junjie. Research on the band gap and attenuation characteristic of sound radiation for periodic compound plate [J]. Journal of Vibration and Shock, 2017, 36(11): 188-191.
LI Suobin, DOU Yihua, CHEN Tianning, et al. Forming mechanisms of low frequency broad band gaps in locally resonant phononic crystal plates [J]. Journal of Xi'an Jiaotong University, 2018, 52(12): 159-166.