On the use of acoustic suspended ceilings with a low height of attachment
Abstract
On the use of acoustic suspended ceilings with a low height of attachment
Incoming article date: 15.04.2021Suspended ceilings constructions can improve the sound insulation of air and impact noise in civil buildings. To minimize the volume of the room, two types of suspended acoustic ceilings are most often used. They are: with the attachment of the structural shell of the ceiling close to the floor slab, and at a low suspension height. The influence of the slab's surface density on the correction to the sound insulation, which is created by the suspended ceiling, both in the first and in the second type, is considered. A method for a correction calculation for the sound insulation due to a suspended ceiling in these cases is given. At a minimum height the method is based on taking into account acoustic power's radiation coefficient of the shell. While for the low suspension height the method deals with the vibration's transmission from the floor slab to the ceiling's shell through the air layer and through the metal fasteners, that in this case become acoustic bridges. As a result, the formula of frequency response for sound pressure lowering, due to the sustained ceiling structure, is obtained. The influence of plasterboard suspended ceiling's perforation on the sound insulation of the entire floor structure is evaluated.
Keywords: suspended ceiling, impact noise isolation, airborne noise isolation, acoustic radiation power, limit frequency, acoustic bridge, acoustic impedance, vibration velocity level, porous and fibrous material, perforated plasterboard