Building Acoustics

300 Building acoustics 3 11 high (^13216) Eh BBBB≈+=⋅≈. (8.31) Between these extremes the bending stiffness of the element will ...

Multilayer elements 301 (^) eff^24 B^4 eff B and. m B Bc k m ==ωω (8.37) Figure 8.20 shows a typical example of the frequency de ...

302 Building acoustics and thickness we obtain a more or less “flat” part on the curve before reaching coincidence. It is also i ...

Multilayer elements 303 63 125 250 500 1000 2000 4000 Frequency (Hz) 0 10 20 30 40 50 Sound reduction index (dB) Core thickness ...

304 Building acoustics (^) () () 2 00 sa 00 00 sa ,cos cos cos c ZZ cc ZZ U τMθ M UU MM − = ⎛⎞⎛ ⎜⎟⎜++ ⎝⎠⎝ . ⎞ ⎟ ⎠ (8.38) a) b) F ...

Multilayer elements 305 () ()() 1 2 c^22 dil c (^2222) 211 1 2 1 where. 21 6 K E fK h hh X πXU U ⎡⎤ ⎢⎥ − ==⎢⎥ ⎢⎥⎛⎞ −+ ⎜⎟+ ⎢⎥⎣⎦⎝⎠ ...

306 Building acoustics measurements was a little smaller than required for a standard laboratory measurement, which is 10 m^2. T ...

Multilayer elements 307 The top layer or floating floor may either be characterized as locally or resonantly reacting, which her ...

308 Building acoustics slabs, characterized by their mass and bending stiffness and coupled together by an elastic layer charact ...

Multilayer elements 309 With the last limit value we have assumed that the impedance of the primary slab is much larger than for ...

310 Building acoustics 63 125 250 500 1000 2000 4000 Frequency (Hz) 0 10 20 30 40 50 60 70 80 Reduction in impact sound level, ' ...

Multilayer elements 311 At very low frequencies one may see frequency dependence near to the Cremer model whereas at higher freq ...

312 Building acoustics The last term only applies to frequencies above fz, a frequency that is determined by the ratio between t ...

Multilayer elements 313 8.4.2.1 Lightweight primary floor In all examples shown relating to the improvement gained from floating ...

314 Building acoustics governing equations for two plates connected and stiffened by beams. In several cases, Brunskog and Hamme ...

Multilayer elements 315 8.4.3 The influence of structural connections (sound bridges) Structural connections, which we may refer ...

316 Building acoustics should be obvious that such stiff connections along the boundaries have a destructive effect on the worki ...

Multilayer elements 317 (^0) 1 , 2 s f π m = (8.49) where s is the total stiffness per unit area of the elastic layer. For porou ...

318 Building acoustics (8.50). In cases where r < 10 kPa·s/m^2 , moreover when we cannot assume that sskeleton >> sair ...

Multilayer elements 319 (^) covering h. ES s d ⋅ = (8.51) The quantities E and d are the E-modulus and thickness of the covering ...