RESONANT SHEET MEMBER, RESONANT STRUCTURE USING THIS, AND MANUFACTURING METHOD OF RESONANT SHEET MEMBER

To provide a sound insulation sheet member that is relatively lightweight, yet has high sound insulation performance that surpasses mass law, and has excellent manufacturability and durability.SOLUTION: In a sound insulation structure 200, a sound insulation sheet member 100 comprises a sheet 11 having rubber elasticity, a plurality of resonance portions 21 provided in contact with a sheet surface 11a of the sheet 11, and at least one or more ribbed projections 31 provided on the sheet surface 11a. The resonant portions 21 are configured as a composite structure with a base 22 and a weight 23 supported by the base 22 and having a mass greater than the base 22, and function as a resonator having a resonant frequency determined by the mass of the weight 23 acting as a weight and a spring constant of the base 22 acting as a spring.SELECTED DRAWING: Figure 1 【課題】比較的に軽量でありながらも質量則を凌駕する高い遮音性能を有し、製造性及び耐久性に優れる遮音シート部材を提供する。【解決手段】遮音構造体２００において、遮音シート部材１００は、ゴム弾性を有するシート１１と、シート１１のシート面１１ａ上に接して設けられた複数の共振部２１と、シート面１１ａ上に設けられた少なくとも１以上のリブ状突起部３１と、を備える。共振部２１は、基部２２と、基部２２に支持され、且つ、基部２２より大きな質量を有する錘部２３と、を備える複合構造体として構成され、錘として働く錘部２３の質量と、バネとして働く基部２２のバネ定数により決定される共振周波数を持つ共振器として機能する。【選択図】図１