Prediction of Maximum Time-Weighted Sound and Vibration Levels Using Transient Statistical Energy Analysis. Part 1: Theory and Numerical Implementation

Transient sounds often have an adverse effect on human occupants in the built environment for which annoyance and sleep disturbance are assessed using the Fast or Slow time-weighted maximum sound pressure level. For this reason there is a need for a validated model that can predict maximum levels due to transient excitation in buildings over the audio frequency range. In this paper, an approach based upon Transient Statistical Energy Analysis (TSEA) is proposed for both maximum sound pressure levels and maximum vibration levels. Three key aspects of TSEA are developed: the requirements for the time interval; the implications of using steady-state SEA coupling loss factors; and definitions of measured, hybrid and synthetic 'transient power' inputs. A proposal is also made to modify the signal processing when measuring maximum vibration levels on source subsystems such as walls/floors where the measurement needs to be compared with predictions using TSEA. Numerical simulations and measured force and vibration data are used to demonstrate the TSEA modelling requirements and to quantify potential errors. Part 2 of this paper contains experimental validation of the approach to TSEA modelling that is introduced in Part 1.