First large-scale application of sprayed GRC in the Netherlands
The Concert Hall in Amare is the first large-scale project in the Netherlands where sprayed glassfibre reinforced concrete has been applied. Glassfibre reinforced concrete (GRC) is mainly used as a cladding material for exterior facades. But in Amare GRC is applied in the acoustic panels and balcony elements indoors. The high demands regarding aesthetics of the interior and acoustics of the concert hall were decisive in choosing for GRC.
Concert hall as musical instrument
Like building a big musical instrument. With this approach, JCAU Architects & Urbanists designed the concert hall and took care of the aesthetic management of the integration of all technical requirements in the interior. With users such as the Residence Orchestra and the Royal Conservatory, a prestigious appearance and top acoustics were absolute requirements. For the architectural finishes, natural materials with a pure expression were used that integrally met the high acoustic requirements. With help of the internationally operating Studio DAP, specialized in concert hall acoustics, the design team ensured that Amare technically meets the latest state of the art. Successfully! The musicians' experiences after the first rehearsals are very positive.
Concrete contributes to visual and acoustic experience
When you think of concrete, who thinks of pleasant acoustics? But it is precisely the combination of limited mass and virtually unlimited freedom of shape of GRC that has led to a perfect performance. The acoustic panels have carefully designed kinked shapes. The faceted surfaces ensure an optimal spread in the reflection of sound frequencies. They also create a very spatial three-dimensional experience. These origami-like elements alternate with niches of flat elements in GRC. With gold-coloured and perforated sliding panels in these niches, the sound absorption in the room can be adapted to the music style, from intimate to electronically amplified. The curves of the balcony edge elements are also important for the acoustic and visual experience. All GRC elements are executed in its natural white color.
Efficient material use for high-end products
The standard thickness of the prefab GRC elements is extremely thin, starting from just 12 mm. For optimal acoustics in the concert hall, the thickness of the GRC of the 850 acoustic wall panels has been increased to 25 mm. Behind it is a layer of 100 mm thick insulation material. The GRC of the 108 balcony edge elements is 15 mm thick. The material is sprayed in single-sided moulds. So both for the end products and during the production process very little material is being used as efficiently as possible. Moulds were produced in such a way that repetition and variation were cleverly alternated.
Due to the combination of low weight, a long lifespan of more than 100 years, the freedom of form and its high aesthetic quality, sprayed glassfibre reinforced concrete offers versatile and sustainable options for many building projects. GRC is high-end, but certainly financially feasible once the knowledge of the producer is used in the design and development process in a timely manner.
The GRC for Concert Hall Amare is produced by BB fiberbeton, Danish market leader in GRC and Full Member of the GRCA (the International Glassfibre Reinforced Concrete Association), and supplied by Hi-Con Netherlands, on behalf of Bouwcombinatie Cadanz (Boele & van Eesteren | Visser & Smit Bouw). JCAU Architects & Urbanists, together with NOAHH (Network Oriented Architecture) responsible for the overall design of Amare, aesthetically assessed and approved the GRC elements. On the advice of Hi-Con, Bouwcombinatie Cadanz has commissioned Van Boxsel Engineering for the engineering of the sub-structure. The mounting of the GRC elements was carried out by EBRS.