Performance of Building Base Isolation: The Two-Level Approach
54º Congreso Español de Acústica — Tecniacústica 2023
Abstract
In buildings close to transit hubs, it is common to observe important levels of structure borne noise inside the buildings. For new constructions, the use of a Building Base Isolation (BBI) is a relatively cost effective solution to mitigate the ground-borne vibrations propagating in the building. In practice, the choice of the BBI system depends principally on the acoustic requirements proposed by the acoustic consultant. The resonance frequency to be achieved is prescribed following different in-situ measurements and a numerical modelling which allows an estimation of the level of structure-borne noise expected in the building. However, the main decision is very often based on the peak frequency observed. Once the resonance frequency is set, a design of the isolators is then proposed based on the load scheme. This paper discusses the traditional approach and based on a real case study, the overall performance of the isolation is critically analyzed not only at peak frequency, but also taking into account the real building behavior and the possibility of resonances after the BBI implementation.