ACOUSTIC INSULATION PROVIDED BY A SINGLE WALL SEPARATING TWO CONTIGUOUS TUNNELS VIA BEM

This paper describes the computation of the acoustic insulation provided by a single simple wall separating two contiguous tunnels when a steady state, spatially sinusoidal, harmonic line load pressure excites one of the tunnels. The Boundary Element Method (BEM), formulated in the frequency domain, is used to compute the acoustic pressure in the two tunnels. The insulation conferred by the wall is characterized, identifying the location of insulation dips in the frequency domain with those dips related to its own natural dynamic vibration modes and those related to the natural vibration modes of the tunnels. This model is also used to assess how the dimension of the rooms, and the rigidity and thickness of the wall affect acoustic insulation. The transmission loss results obtained via the BEM are then compared with those provided by simplified analytical models such as the mass law.

[1]  L. R. Quartararo,et al.  Noise and Vibration Control Engineering: Principles and Applications , 1992 .

[2]  N. Cook,et al.  Analysis of borehole breakouts , 1989 .

[3]  Leo L. Beranek,et al.  Noise and vibration control , 1971 .

[4]  B. Gibbs,et al.  Application of a finite-element model to low-frequency sound insulation in dwellings. , 2000, The Journal of the Acoustical Society of America.

[5]  D. I. Gough,et al.  Northeast-southwest compressive stress in Alberta evidence from oil wells , 1979 .

[6]  Albert R. George,et al.  AN EMPIRICAL SCHEME TO PREDICT THE SOUND TRANSMISSION LOSS OF SINGLE-THICKNESS PANELS , 1999 .

[7]  R F Job,et al.  Sources and effects of low-frequency noise. , 1996, The Journal of the Acoustical Society of America.

[8]  Eric E. Ungar Statistical Energy Analysis of Vibrating Systems , 1967 .

[9]  J. Mathys,et al.  Low-frequency noise and acoustical standards , 1993 .

[10]  L. Rayleigh,et al.  The theory of sound , 1894 .

[11]  Robert J.M. Craik,et al.  Sound transmission through double leaf lightweight partitions part I: airborne sound , 2000 .

[12]  Paul Klinge,et al.  Prediction of structure-borne sound transmission in large welded ship structures using statistical energy analysis , 1995 .

[13]  L. Gagliardini,et al.  The use of a functional basis to calculate acoustic transmission between rooms , 1991 .

[14]  Michel Bouchon,et al.  Numerical Simulation of the Acoustic and Elastic Wavefields Radiated by a Source in a Fluid-filled Borehole Embedded in a Layered Medium , 2022 .

[15]  Gerrit Vermeir,et al.  Low-Frequency Airborne Sound Transmission through Single Partitions in Buildings , 1997 .

[16]  A. London Transmission of Reverberant Sound through Double Walls , 1949 .

[17]  Djamel Ouis Scattering by a barrier in a room , 1999 .

[18]  E. C. Sewell Transmission of reverberant sound through a single-leaf partition surrounded by an infinite rigid baffle , 1970 .

[19]  I. I. Novikov Low-frequency sound insulation of thin plates , 1998 .

[20]  Gerrit Vermeir,et al.  Numerical simulation of airborne sound transmission at low frequencies: the influence of the room and the partition parameters , 1997 .

[21]  N. Atalla,et al.  A numerical model for the low frequency diffuse field sound transmission loss of double-wall sound barriers with elastic porous linings , 2000 .

[22]  Ben H. Sharp,et al.  Prediction Methods for the Sound Transmission of Building Elements , 1978 .

[23]  Robert J.M. Craik,et al.  Statistical Energy Analysis Of Structure-borne Sound Transmission By Finite Element Methods , 1994 .

[24]  R.N.S. Hammad Simulation of noise distribution in rectangular rooms by means of computer modelling techniques , 1988 .

[25]  Gerrit Vermeir,et al.  Low-frequency airborne sound transmission through single partitions in buildings , 1997 .

[26]  Robert J.M. Craik,et al.  Sound transmission through lightweight parallel plates. Part II: Structure-borne sound , 2000 .

[27]  Keiiti Aki,et al.  Discrete wave-number representation of seismic-source wave fields , 1977, Bulletin of the Seismological Society of America.

[28]  M. Nafi Toksöz,et al.  Borehole Seismic Source Radiation In Layered Isotropic And Anisotropic Media: Boundary Element Modeling , 1995 .

[29]  Yih-Hsing Pao,et al.  Diffraction of elastic waves and dynamic stress concentrations , 1973 .

[30]  Paulo Santos,et al.  Closed-form integration of singular terms for constant, linear and quadratic boundary elements. Part 2. SV-P wave propagation , 1999 .

[31]  Richard H. Lyon Statistical energy analysis of dynamical systems : theory and applications , 2003 .

[32]  Raymond M. Brach,et al.  Statistical Energy Analysis of Dynamical Systems: Theory and Applications , 1977 .

[33]  R. Wilson Sound transmission through buildings using statistical energy analysis , 1998 .

[34]  C. J. Randall Modes of noncircular fluid-filled boreholes in elastic formations , 1991 .

[35]  Paulo Santos,et al.  3-D wave propagation in fluid-filled irregular boreholes in elastic formations , 2001 .