The “SuperHub” is a forward-thinking, sustainably designed multifunctional building. Through an iterative process, the structural engineers successfully brought the visible timber construction to life while ensuring its stability. They utilised SCIA Engineer software for the modelling and structural analysis of the load-bearing structure.
Located on the eastern outskirts of Groningen, a Dutch city, a new neighborhood with around 5,000 homes is set to expand gradually over the next decade. The completion of the SuperHub, which currently houses a supermarket, café, and health centre, has addressed the need for a central gathering space in the area.
Thanks to the prefabrication of all building components, the SuperHub was completed within a short construction period, just over two years ago.
Timber as a key design feature
The expansive market hall, with its cathedral-like appearance featuring a large span and 9-meter high ceilings, covers a gross floor area of 2,090 sq m.
Timber columns arranged in a grid surround the space, with a building-high, non-loadbearing curtain wall made of glass and steel. The curved windows at the rounded corners of the oval building provide thermal insulation to Passivhaus standards, ensuring bright and well-lit interiors.
The timber structure has a positive environmental impact and was designed for long-term sustainability. The large span and high ceilings offer flexibility for resource-efficient building conversions, meeting the evolving demands of future use.
The spacious roof provides ample room for greenery and a photovoltaic system. Additionally, the integrated air treatment system and heat and cold storage in the floor ensure a comfortable and energy-efficient indoor climate.
22 glued laminated timber pillars support the flat roof
The 9-meter-high flat roof is formed by a diagonal grid of glued laminated timber beams, with a 5.4-meter overhang on all sides. It is supported by 22 pillars arranged in a 10.8m x 10.8m grid.
The pillar design is tree-like, with each consisting of four curved glulam supports that branch out at the top to form a cross shape. Steel connectors, hidden from view, hold the glulam supports together at the joints. Beams extend from the end of each “tree” support, creating the lattice-like structure of the symmetrical roof.
Loadbearing structure represented as a 3D structural analysis model
Structural engineer Pieters Bouwtechniek handled the structural design of the SuperHub.
“The complex interplay of forces in the cantilevered roof structure and its interaction with the tree-like timber supports could only be properly captured in a 3D analysis model,” says Steven van Eck, structural engineer at Pieters Bouwtechniek.
To achieve this, the engineers used the multi-material structural analysis software SCIA Engineer for both modeling and structural analysis.
Refined design process for connection details
“We initially put a lot of effort into designing the connection details for the timber components, because the design of the connections has a significant influence on the entire loadbearing structure and its structural analysis,” recalls van Eck.
“On the way to the final model, we tested various systems of continuous beams and single-span beams in SCIA Engineer in numerous iterations, in which the arrangement of the hinges and the rotational stiffness of the connections varied constantly.”
At the same time, the team significantly reduced the time spent modeling the ‘tree’ columns.
“We modelled a pillar with its four glulam columns and the beams, as well as the steel connections, and then duplicated them by copying and pasting in the grid,” said van Eck, who managed to model 90% of the structure in a remarkably short time using this approach.
Structural analysis using SCIA Engineer
For most calculations, the structural engineers performed linear static analyses in SCIA Engineer.
Given the building’s location near an earthquake zone, earthquake analyses were also conducted using the modal method and the multimodal response spectrum method.
The engineers calculated the base shear force, which was then used to demonstrate that wind loads are more critical than seismic loads.
Additionally, the SCIA Connection Forces function was employed to efficiently determine the forces of the key connection details. SCIA Engineer’s calculation report enabled the team to quickly generate the structural calculation output for model documentation.
“I like using SCIA Engineer because, thanks to the many modelling and calculation options, I can create a customised and workable design for any project, no matter how complex, and let the software do the work for me,” concludes van Eck.
Original source: PBC Today
