Design and verification of vibration isolation of buildings against structure-borne noise, generated by trains

Structure-borne noise generated by trains, including both underground metros, surface trams and local or large-distance train lines, raise more and more environmental problems in densely populated residential areas. An emerging technology is to use elastic support elements in the building construction, manufactured from elastomer materials or even steel in case of strict requirements. The traditional design method of these isolation systems is based on very simple, SDOF models, even though more sophisticated, numerical techniques also come into general use nowadays. The paper discusses a few modelling approaches and compares the obtained results to experimental data. The issue of selecting correct, yet easily manageable descriptors for verification purposes (in particular, the well-known Insertion Loss vs. Transmission Loss discrepancy) is analysed on medium-sized models by numerical simulation. The trade-off between optimal selection of design frequencies of the building vibration isolation against ground-borne vibrations, and of the floating floor used to increase the impact sound insulation between apartments above each other is also tackled. The treatment of the paper is concentrating on the practical engineering applications of novel techniques rather than developing new ones