Federica Bettarello

Impact Sound Pressure Level Performances of Basic Beam Floor Structures

In order to obtain reliable estimations of the impact sound insulation between rooms, it is necessary to know the acoustic performance of each element composing the floors. The contribution of the flanking transmissions, the attenuation of floating floors and the weighted normalized impact sound pressure level of the basic structure need to be determined in order to apply the simplified calculation method according to the EN ISO 12354-2 standard. With the aim of verifying the range of validity of the calculation method proposed by the EN ISO 12354-2 standard for typical basic beam floor structures, a research based on on-site measurements was conducted. This paper provides an analysis in terms of spectrum trend, predicted average weighted normalized impact sound pressure level and reduction of impact sound pressure level obtainable with a generic floating floor typology. The study can represent a starting point for a correct estimation of the impact sound insulation in new buildings and renovation plans.

Thermal and acoustic performance expectations on timber buildings

In recent years, building technologies have been developed in order to improve comfort and energy saving. European institutions and single countries firmly invite individuals to choose high energy-saving strategies in order to decrease carbon emissions and energy consumption. Examples could be found in thermal insulators added to façades and improvement of glazing performance. At present, two technologies are the most used in construction realization: traditional (concrete, masonry or in general heavyweight structure) or wood (timber, crosslam or in general timber lightweight structure). Designers, scientists and builders have their own opinions on these two topics, but good insulation performance are achievable with both of them. Nevertheless, for lay people as well as for designers, wooden structures seem more comfortable, reliable and insulated. Therefore, an international survey was realized in order to investigate what individuals expect from these two different construction technologies in terms of insulation performance. Results indicate that timber buildings stereotypes are confirmed for acoustic and thermal insulation and show how scientific communication may help to deal with new or untraditional constructions.

Low frequency noise and disturbance assessment methods: A brief literature overview and a new proposal

Several studies have presented the effects of environmental noise on communities, focusing attention on sleep time events. The noise introduced into a dwelling is mostly evaluated using the A-weighted sound pressure level (LAeq) as the only parameter to determine the perceived disturbance. Nevertheless, if noise is produced by activities or sources characterised by a low frequency contribution, the measurement of LAeq underestimates the real disturbance, in particular during sleep time. The aim of this contribution is to analyse the low frequency disturbance phenomenon into technical and scientific literature and to investigate if any possible objective method is available in order to assess noise disturbance inside dwellings.

The Royal Church of San Lorenzo in Turin: Guarino Guarini and the Baroque architectural acoustics

In 1666 the architect Guarino Guarini received from Carlo Emanuele II, Duke of Savoy, the appointment to build in Turin a new church dedicated to S. Lorenzo. The architect conceived a design in Baroque style with a very particular ribbed dome and this peculiarity is a very hard to find feature throughout Europe. Acoustics measurements were performed in S. Lorenzo in order to investigate how this unique architecture affects the response parameters used in architectural acoustics. Results are discussed in the paper, comparing to the methodology suggested by Cirillo and Martellotta in order to characterize the acoustics of churches.

Effect of the frequency spectrum trend on the determination of the weighted normalized impact sound pressure level for floor structures

The most common floor constructions in Italian buildings are composed of two parts: the structural one, made of concrete beams and perforated bricks, and the floating floor. The results of the in situ measurements of the impact sound pressure level, realized on the structural part of the floors, show a frequency spectrum trend that increases with the frequency. The spectrum is also characterized by many peaks and dips at the high frequency range that strongly influence the determination of the weighted normalized impact sound pressure level, also for structures with similar mass and geometry. The frequency trend of the beam and brick structures is completely different from the characteristic spectrum of homogeneous concrete slabs or lightweight structures. Considerations on how those differences can influence the obtainable results in terms of the reduction of impact sound pressure level referred to the same floating floor typology, the spectrum adaptation terms and the other acoustic quantities described...