Minimization of sound radiation in doubly curved shell structures by means of stiffness

Méndez Echenagucia T., Roozen B. and Block P.
Proceedings of the International Association for Shell and Spatial Structures (IASS) Symposium 2016
Tokyo, Japan
2016

A large amount of the embedded energy of buildings is due to their structures. Consequently, designers have been developing lighter and material efficient structures. However, lightweight structures are vulnerable to aerial and structure-borne noise transmission, especially for the lower frequencies. Sound insulation from environmental noise or footfall is commonly addressed by increasing the mass of the structure, resulting in inefficient constructions. In the lower frequency range, structural stiffness plays a significant role in preventing sound transmission. This paper studies the relationship between stiffness and the acoustical insulation properties of shallow structural shells. The sound radiation of doubly curved shells, under point loads, is estimated by computing the surface normal velocity using Finite Element Method and the radiated sound power using the Rayleigh Integral. The paper shows the potential of optimizing shallow shells for sound transmission by means of their shape, the distribution of mass, and the topology of stiffening ribs.