Prediction of impact sound on light weight floor structures

摘要

The interest for light weight building techniques have increased during the last years. In a historical point of view it is however known that this type of floors have very poor impact sound insulation. During the late 80's new type of structureshave been developed that have an acceptable sound insulation [1].To design a light weight floor structure properly there are a lot of parameters that can be important; e.g. mass per unit area in the bottom and top plate, mass per unit length beams, stiffness in the bottom and top plate, stiffness beams, cavity, i.e.air coupling via the isolation, damping, coupling between plate-frame-plate, geometry, et cetera. In order to combine this degree of freedoms properly a theoretical model is needed. The system that will be considered consists of two parallel platescoupled trough a partly filled cavity and reinforced by two sets of beams, and a transform technics will be used. A system with one set of beams has been treated by Evseev [2], and a plate with two sets of beams have been treated by Mace [3]. Lin andGarrelick [4] has treated two parallel plats coupled via a cavity and one set of beams. A non-recoupling between the floor and the ceiling is presented by the authors in [5, 6].