Modelling vibration transmission on frameworks of beams using Advanced Statistical Energy Analysis

To account for indirect coupling and high propagation losses on frameworks of coupled beams, Advanced Statistical Energy Analysis (ASEA) has been used to study bending and torsional wave models, and bending and longitudinal wave models on frameworks of beams. At high-frequencies, Timoshenko theory was incorporated into ASEA by changing the group velocity used to calculate the coupling loss factors, but maintaining the Euler-Bernoulli beam transmission coefficients. Comparisons of FEM, SEA and ASEA show that high propagation losses can occur with a rectangular beam frame, while tunneling exists in a three-bay linear grillage which has relative short beam lengths. Unlike SEA, ASEA is shown to be able to account for the indirect coupling and these losses. For a three-bay linear grillage, comparisons with FEM show that ASEA is able to predict the response on the 'perfectly periodic' structure as well as a more realistic engineering structure with uncertainty in the Young's modulus.