Figure 2 - uploaded by Alessandro Schiavi
Content may be subject to copyright.
Sound absorption coefficient of the three prototypes tested in reverberation room.

Sound absorption coefficient of the three prototypes tested in reverberation room.

Similar publications

Conference Paper
Full-text available
W pracy zbadana została efektywność sorpcji barwników Reactive Black 5 – RB5 (Czerń helaktyno-wa B) i Basic Green 4 – BG4 (Zieleń borucelowa KM) na zeolicie niemodyfikowanym, oraz zeolicie modyfikowanym 6M NaOH. Oba sorbenty testowane były w formie drobnoziarnistej (Ø 0,5-1,0 mm) i gruboziarnistej (Ø 2,0 -3,0 mm). Do opisu sorpcji barwników na sorb...

Citations

... Results obtained by Candelari [44] and Serra [27] showed that the high values of the sound absorption coefficient between 250 Hz and 3800 Hz were mainly due to the presence of the growing medium. In dry conditions, the presence of different typologies of leaves did not influence the acoustic performances of the VGS; on the other hand, in wet conditions, the acoustic performances of the VGS decreased, since the water inside caused the density of the growing medium to increase and filled the open pore voids. ...
... In dry conditions, the presence of different typologies of leaves did not influence the acoustic performances of the VGS; on the other hand, in wet conditions, the acoustic performances of the VGS decreased, since the water inside caused the density of the growing medium to increase and filled the open pore voids. In our study, we found that with dry felts the absorption coefficient at highest frequencies is lower than with wet felts, while Attal [31], Candelari [44] and Serra [27] found exactly the opposite situation, because of the presence of the substrate. In particular, Serra [27] found that in wet conditions the acoustic performances of the VG decreases, since the water inside increased the density of the substrate and filled the open pore voids. ...
Article
Indoor living walls are important decorative elements that can recreate a natural garden in enclosed spaces. Several aspects are addressed by the scientific literature such as, for instance, classification, the effects on air quality and indoor temperature, greater aesthetic and psychological impact, and improved acoustic treatment of indoor spaces. The main objective of this study is to analyse the acoustic performances of a novel indoor living wall (LW) where plants are rooted in felt layers and grown in hydroponics with no growing medium. The sound absorption of different LW solutions was measured in laboratory (reverberation room). One of them was installed in a Test Building, where sound absorption and sound insulation were measured. The LW has been installed for about two years in the Test Building under controlled conditions of temperature and relative humidity. This gave the unique opportunity to test the sound absorption of the same living wall in the same reverberation room after about two years. The results obtained indicate that the sound absorption performance of the LW is stable, as long as the plants remain in good health. Moreover, an estimation was performed with a calculation model of the reverberation time of the room containing the living wall. Evaluation in real working conditions confirms that indoor living walls can improve the acoustic comfort of indoor spaces by increasing both the sound insulation and the sound absorption area, allowing to reach the optimal reverberation time values provided for by Italian regulations.
... The VGS benefits are therefore also transmitted to the urban scale, where they can also act positively on the urban sound propagation, mitigating the classical Bacoustical canyon effect^produced by multiple reflections of sound in city streets framed by buildings (Ismail, 2013 andCandelari et al. 2013). An experimental study analysed different VGS to evaluate their acoustic impact (Wong et al. 2010b). ...
Article
Full-text available
Vertical greenery modular systems (VGMSs) are an increasingly widespread building envelope solution aimed at improving the aesthetical quality of both new and existing façades, contemporarily achieving high energy efficiency performance. Within a research project, a new prototype of VGMS was developed, designed and tested. An experimental monitoring campaign was carried out on a test cell located in Turin (northern Italy), aimed at assessing both biometric parameters and energy-related issues. Two different types of growing media and two plant species, Lonicera nitida L. and Bergenia cordifolia L., have been tested on a south-facing lightweight wall. Results have been compared to the same wall without VGMS and plaster finished, in order to characterise the thermal insulation effectiveness in the winter period and the heat gain reduction in the summer period. Measured equivalent thermal transmittance values of the green modular system showed a 40 % reduction, when compared to the plastered wall, thus noticeably impacting on the energy crossing the façade during the heating season. Benefits of the VGMS are measured also during the summer season, when the presence of vegetation lowers the outdoor surface temperatures of the wall up to 23 °C compared to the plastered finishing, with a positive effect on outdoor comfort and urban heat island mitigation. Nevertheless, as far as the entering energies are concerned, not significant reduction was observed for VGMS, compared to the reference plastered wall, since the green coverage acts as a thermal buffer and solar radiation is stored and slowly released to the indoor environment.
... The sound absorption coefficient, in the 100 Hz to 3800 Hz frequency range, was determined at normal incidence α 0 . The measurement provides accurate results [47], even for extremely heterogeneous and anisotropic materials, such as the examined stratigraphy. The technique is based on the measurement of a transfer function between the sound pressure measured by two microphones within the tube, when the tube is excited by a loudspeaker placed at one end, while the specimen is placed at the other end of the tube. ...
Article
Vegetation in architecture can be considered a proper design strategy that is aimed at improving not only the performances of buildings, but also the outdoor climate. Different technological solutions have been proposed over the years to cover buildings with vegetation, i.e. green roofs, green walls and green balconies. A particular typology of green wall, which has recently been gaining high consensus among designers, is the vertical greenery modular system (VGMS). The positive impact of this type of technology on the performance of buildings is related to several factors, such as the façade orientation, the use of the building, climatic conditions, the type of plants, the substrates and wall assemblies, as well as mechanical and technological issues. A multidisciplinary approach is therefore needed, and different skills have to be joined together right from the early design phase in order to optimize and balance all the aspects that are involved. In this framework, a research project has been carried out in Turin (North West Italy), with the aim of developing a novel VGMS, constituted by a modular box covered with vegetation, made up of recycled/natural and highly performing materials from the energy/environmental point of view. After the design phase, the actual performance of the VGMS was assessed, through laboratory and long-term in field monitoring, and at the same time, the technological issues, biometric parameters, and the acoustic, thermal and mechanical aspects were investigated.
... Ne sono un esempio le misure effettuate su file di poltrone utilizzate in teatri e cinema (a seduta aperta o chiusa) o su 42° Convegno Nazionale AIA barriere antirumore (ferroviarie o autostradali). Recentemente sono state effettuate prove su diverse tipologie di pareti verdi di facciata, in funzione di sistemi fogliari e sistemi di ancoraggio differenti [5]. Particolarmente interessante, proprio in funzione di superfici molto irregolari o caratterizzate da geometrie non isotrope, è la possibilità di definire e quantificare sperimentalmente gli effetti di scattering, per applicazioni specifiche dell'acustica architettonica [6]. ...
... La diusione di facciate vetrate ha degli svantaggi: le elevate dispersioni termiche nel periodo invernali e gli elevati carichi solari nel periodo estivo. Probabilmente proprio in risposta alle criticità degli edici vetrati intorno agli anni ' 30 Le Corbusier formula la sua idea di mur neutralisant e la respiration exacte. Per la prima volta si formula la possibilità di associare tecniche passive e attive per il controllo dei ussi energetici in un edicio. ...
... L'applicazione di un elemento verde garantisce un miglior potere fonoisolante della tecnologia perchè aumenta la massa del componente. Alcuni risultati sembrano suggerire un eetto beneco sul clima acustico esterno, una riduzione dell'inquinamento acustico grazie all'elevato potere fonoassorbenete di alcune specie vegetali [30]. Su una scala più ampia l'applicazione di tecnologie verdi è vantaggiosa per la riduzione dell'isola di calore, la riduzione degli inquinanti in aria grazie all'eetto ltrante delle piante. ...
... Il terzo modello con RLM Il terzo modello è stato applicato al SET 1 per calcolare i coecienti δ. Si noti che i valori di energia e di usso termico dieriscono rispetto a quelli degli altri modelli perché in questo caso non sono specici (al metro quadro), ma sono moltiplicati per l'area della facciata climatica di 12,62 m 2 , secondo l'equazione 6. 30. I risultati delle simulazioni sono stati riportati solo per le equazioni con il termine noto pari a zero, in quanto con il Tabella 9.7: I valori dei coecienti β 24 calcolati con l'equazione delle energie totali giornaliere (RLM1). ...
Thesis
Con l'entrata in vigore della Direttiva europea 2009/91/CE (EPBD) e s.m.i. si pone l'attenzione verso la promozione di interventi sul patrimonio edilizio volti alla costruzione di nuovi edifici ad energia quasi zero (NZEB Nearly Zero Energy Building), ovvero edifici ad altissima prestazione energetica. Per il raggiungimento degli obiettivi imposti a livello europeo è necessaria una trasformazione del concetto di involucro edilizio; da semplice elemento di chiusura dal contesto climatico esterno, definito "involucro passivo", a pelle, elemento regolatore attivo in grado di modulare l'interazione tra ambiente interno e ambiente esterno (involucro "dinamico"). Questo nuovo approccio ha portato allo sviluppo di tecnologie che promuovono l'adozione di componenti dinamici adattativi/responsivi nell'involucro edilizio e negli elementi costruttivi (Annex 44), fortemente integrati con gli impianti meccanici e con sistemi atti allo sfruttamento dell'energia solare. In questo quadro, dall'analisi dello stato dell'arte sono emersi due principali limiti tecnici all'adozione e allo sviluppo di tecnologie di involucro responsivo; la carenza di indicatori sentitici normati e in grado di rappresentare il comportamento dinamico dei sistemi di involucro edilizio e la mancanza di strumenti semplificati per la simulazione energetica in una fase di progetto preliminare. Il lavoro di ricerca si focalizza in particolare sulle tecnologie di involucro trasparente con un comportamento responsivo infatti la trasparenza è una scelta architettonica sempre più diffusa negli edifici ad uso terziario. L'analisi parte dalla scala del componente per arrivare a quella di sistema di facciata trasparente. Grazie ai dati raccolti durante cinque diverse campagne sperimentali su componenti e sistemi di facciata trasparenti si propone una metodologia di acquisizione dei dati sperimentali, di elaborazione critica dei risultati e di normalizzazione per il confronto tra le diverse tecnologie. Tra i sistemi di facciata analizzati una facciata climatica è stata caratterizzata dal punto di vista termico, acustico e luminoso tramite l'elaborazione di dati sperimentali. Dall'elaborazione di una parte dei dati sperimentali si sono definiti i parametri sperimentali sintetici di trasmittanza termica (U) e fattore solare (g) tramite il metodo delle regressioni lineari e multiple. I parametri calcolati sono stati validati su un altro set di dati sperimentali. I risultati mostrano che l'utilizzo di parametri sintetici per caratterizzare il comportamento di sistemi di facciata attiva porta ad un errore di circa il 25%. Parallelamente si è sviluppato un nuovo modello di calcolo semplificato orario, per valutare la prestazione energetica di sistemi di facciata attivi. Il modello è stato validato su diverse configurazioni di facciata attiva e con i dati raccolti in campo.Infine si è effettuato un confronto tra i risultati del modello semplificato e di un modello dettagliato e capacitivo
... The VGS benefits are therefore also transmitted to the urban scale, where they can also act positively on the urban sound propagation, mitigating the classical Bacoustical canyon effect^produced by multiple reflections of sound in city streets framed by buildings (Ismail, 2013 andCandelari et al. 2013). An experimental study analysed different VGS to evaluate their acoustic impact (Wong et al. 2010b). ...
Article
Full-text available
The need for new recycled and low energy products for a greater environmental sustainability is also an issue in landscape planning, and the prerogative of some of the latest technologies in design. One of these technologies is represented by the living walls, and a study is being carried out to trial alternative substrates made of industrial residues. To carry out the trials the Reviwall® (Reviplant, Italy) patented vertical green system was chosen. Since the main aim of the trial was to evaluate the possibility of using alternative and eco-compatible substrates, shredded felt, the industrial residue of the production of chair felt pads, were chosen for substituting the coconut fibre. To verify the suitability of this new material and to identify the better combination of plant and substrate, three different species (Lonicera nitida, Bergenia cordifolia and Luzula sylvatica) were tried on four different substrates composed by different percentages of felts. Six blocks of 216 panels of living walls for a total area of 43 m2 were tested, and 18 plants (3 panels) for each thesis (plant-substrate combination) were randomly organized within each block. Monthly surveys were performed to monitor the growth of the plants and the quality of the green cover, by considering growth and ornamental parameters. The first results allow to assert that felt pads are a valid substitute for coconut fibre for growing plants on living walls, especially with Bergenia and Lonicera, while Luzula gave negative results.