ClientNaturalis Biodiversity Center
ArchitectNeutelings Riedijk Architects
Project size39.000 m2 bvo
Start of project2015
Consulting servicesStructural design, specifications, detail drawings and calculations
The new building consists mainly of halls that are clustered into 3 blocks. The halls within the 3 blocks have different heights, but are placed in relation to each other in such a way that floor levels are corresponding. Between the 3 blocks in 2 strips of 6 m width concrete cores have been realised in which the stairs, elevators and shafts are concentrated. These strips provide stability in one direction. In the other direction no continuous vertical walls are available. Therefor the ‘mountain of stairs’ is used to provide stability. In fact the stepped walls and the stairs form a folded three-dimensional stability element.
The large column free halls with floor spans of 21,6 m are not essential for the museum functions, but after optimisation they appeared to be possible within the financial budget. A very important design criterion was the dynamic and acoustical behaviour of the floor. Parameters that were investigated were: the construction material (steel of pre-stressed concrete), the distance between beams and with this the span of floors. It had to be taken in account that these floors have to be constructed on a height of 12 m. Therefore a self-bearing floor has been designed (a thick wide slab floor). Steel trusses with a height of 1,5 m and a mutual distance of 3 m have been chosen also because of the advantages for the installations. These trusses bear on the concrete cores and on steel columns in the facades. All ducts and vents are installed between the trusses en from there they feed the hall underneath or the raised floor above.
During the development of the design many detail variants have been evaluated, especially in favour of a more sculptural effect in the facades and the for the design of the facades and roof of the entrance hall, also called ‘glass crown’. Cantilevering the steel trusses enabled the stepped façade. The glass crown initially had a simple diamond pattern for which a steel structure in corresponding shape was suitable. Later, because of the need for more sculptural effect and shading, an iconic pattern was created. The structure and materialization was a challenge also because of the large free heights without horizontal supports. Variants in steel with a shaping skin of micro concrete were investigated. In the end prefabricated concrete was chosen, for which the joints have been studied thoroughly. The glass crown is not only the result of integrated design by architect and structural engineer but also of coordination with glass manufacturers. It concerns glass panels with special shapes that have to be able to follow the relatively large deformations in the façade.