Last week I had the pleasure of recording a MOOC Lecture with Prof. Garlock on Contemporary Vaults. This MOOC lecture will be offered in Spring 2018 and I will provide you the details in due time. Much to my excitement we got to spend more than 12 hours underneath the steel/glass cupola of the Dutch Maritime Museum in Amsterdam, the Netherlands. When I worked for Ney and Partners, I carried out the initial form finding of this gorgeous cupola which won the 2012 Amsterdam Architecture Prize. Time for some pictures and closer look at the design approach of this slender cupola.
Prof. Garlock and myself recording the MOOC under the cupola of the Dutch Maritime Museum (left), Schoolchildren gazing at the pattern of the grid of the cupola (right).
In the late seventeenth century, the historic building currently housing the museum, was the headquarters of the admiralship. It was the instrument and symbol of the Dutch maritime power. The development of this sea-faring nation was closely linked to the production of sea charts and the advent of the associated sciences, such as geometry, topography, and astronomy. The historic heavy masonry building also uses geometry as a basis for its design and is arranged around a quasi square courtyard which you can see in the background in the pictures shown above.
In the 20th century, the museum underwent a great restoration and the idea was born to increase the amount of useable floor area by sheltering the inner courtyard with a roof. A design competition was held and the cupola roof design of the design consultancy Ney and Partners was chosen to be built. The new roof is a steel gridshell clad with glass. The choice for the initial two-dimensional (2D) grid topology of the shell tells the spectator a story about the building’s history and its close relationship to the history of the sea. At the origin of this 2D topology lies a loxidrome map with 16 wind roses. This geometric drawing is found on sea charts displayed inside the museum.
We used this 2D topology diagram as the basis for the structural mesh of the roof. Starting from this geometric 2D mesh pattern, we needed to develop an exact 3D grid shell surface.
I used a numerical form-finding technique based on a hanging chain model within a Dynamic Relaxation Solver, and converted the 2D mesh into a 3D efficient shallow shell shape. Due to its efficiency, all the gridshell members can be rather slender and as a result the mesh reads like a line drawing against the sky. Yet the shell’s shape and its slenderness are exclusively grounded in the rational logic of engineering.
The 3D shape of the cupola is derived from a hanging chain model.
The complexity of obtaining planarity in all of the four and five-sided facets of the gridshell was solved by Dr. Chris Williams in a novel, analytical origami approach based on Maxwell reciprocal diagrams.
The structurally efficient and constructible shape of the cupola cannot be obtained by producing this form in an exclusively sculptural, esthetic manner. The freedom in generating the efficient form of the cupola lied in the right selection of the material. the loading and boundary conditions, not in the adherence to geometric and nonuniform rational B-spline surfaces. We wrote a great paper about the form finding procedure of this cupola for those who are interested in the finer grain details. Let me know if you would like to read it. The roof also features on the cover of our book “Shells for Architecture: Form Finding and Optimization.”
Location: Dutch Maritime Museum, Kattenburgerplein 1, Amsterdam, The Netherlands
Author: Sigrid Adriaenssens