Characterisation of time-varying structure-borne sound sources using a reception plate to predict maximum Fast time-weighted levels in heavyweight buildings

Abstract

Structure-borne excitation from many mechanical appliances leads to structural vibration which can be transmitted to nearby rooms and cause annoyance for building occupants. The reception plate method provides a simplified characterisation procedure to obtain the power input for SEA prediction models. Empirical corrections based on the relationship between Leq and LFmax are introduced to predict sound transmission from time-varying source vibrations in buildings. For this purpose, the reception plate method is used to capture the maximum power input. Using different ramped noise signals as idealised versions of time-varying signals from machinery has allowed empirical corrections to be identified such that short Leq measurements can be used with the reception plate. When using SEA or EN12354 it is shown that LFmax in a room can be predicted for a time-varying structure-borne sound source with one-third octave band errors within ±3 dB. Similar results occurred for predicted LAFmax levels calculated from frequency-dependent A-weighted LFmax. A case study with a toilet flush was performed on the reception plate to replicate the empirical corrections derived from ramped noise signals which resulted in close agreement.