Swinging with glass
Creative researchers at Delft University of Technology in the Netherlands have developed a glass swing using glass rods as the construction material. Ate Snijder, one of the developers of this extraordinary project, talks about the project background and its creation.
How did this unusual idea come about?
The glass swing idea was an attempt to bridge the disparity between glass art and architectural glass because little synergy exists between these two fields. Glass art can be sculptural, curvaceous and spectacular, whereas architectural glass tends to be structural, flat and can almost be invisible. Three engineers and educators with a passion for structural design, Prof. ir. Rob Nijsse, ir. Lennert van der Linden and myself often fantasize about and realize ways to do more with glass as a structural material. Our question is: Can the fields of architectural glass and glass art merge to create structures with the qualities of glass art, addressing form, light, playfulness, elegance and function? The swing says yes! With a small team of engineers and students, we have attempted to fully utilize the enormous aesthetic potential of glass while at the same time creating a strong, safe and functional object.
Who had the opportunity to have a go and enjoy the glass swing first?
The visitors of last year´s glasstec special show “glass technology live” in Duesseldorf were the first people to try. The trade show has a history of showing interesting and eye-catching glass objects with a playful character. The presented nine meter long glass slide in 2016 for example was such a fantastic piece; we liked the idea of following up on that. Our swing allowed the visitors to load the structure with their own weight. This gives them a more direct feel for the loadbearing capacity of the glass.
What was the scientific intention and how did you proceed?
Our intent was to find an optimal but at the same time beautiful glass structure for the glass swing. To create both a stable and efficient as possible bearing frame of glass bundle bars my colleague Lennert van der Linden and I used computer aided parametric design techniques. We already knew the technology behind creating safe glass bundle bars, but the required structural nodes to connect the glass bundle bars had to be developed. We decided to use 3D printing to create the steel connecting detail. From the complete overview, each detail was drawn out in a computer program. This information was sent to the 3D printing company Ramlab in Rotterdam. In the workshop of Ramlab the steel connecting parts were 3D printed on steel spheres. At Delft, Kees Baardolf welded the connecting strips to these 3D printed nodes. He also welded the steel beam base frame that the glass swing was placed on.
Did your experiences with glass motivate you to use it again?
No doubt. Every project brings great satisfaction but also a gnawing regret about all the things that could have been done better in hindsight. A new project offers the opportunity to use the lessons learnt. This swing and the former glass bridge project will by no means be the last ones using glass rods.
What was necessary from a material side to realize the swing? Did you get any external support?
SCHOTT was a fantastic partner for the swing. The material was provided cut to length and this was really helpful for the construction. In our publications, presentations and glass education we are happy to mention the collaboration we had in the construction phase of the swing. The quality of the glass has proven to be so high that we were able to weld on the nodes a few centimeters away from the glass, with hot bits of metal sometimes dropping on the glass without breaking it. In addition the 3D printing startup Ramlab have been great to collaborate with in the development and production of the connections.
Why is it so special to work with glass as a construction material?
The most challenging aspect is that you cannot hide anything. People can see right into the material and any bad detailing or damage is immediately visible. The trick is to keep the construction very clean and very simple. Secondly, there are big structural challenges: The structure must be safe, vandalism proof and stresses in the glass must be controlled carefully. Glass is not a very forgiving material in its use in construction. Fortunately, we have an enormous accumulated knowledge and experience here at the university on how to engineer glass structures.
Which idea do you think will come next from you and your students?
We have three solid ideas, which I hope we will incorporate in the coming glass courses for the architecture and civil engineering students. Of course, to be able to realize these we hope to continue and expand our relationship with SCHOTT for their contribution of the necessary materials. The three upcoming structures are spectacular and (I think) very advanced glass-engineering structures. The first is an arch bridge consisting of glass blocks, which are dry-assembled. The second is a spaceframe structure with improved glass struts made from a combination of tubes and rods. The third is a grid shell from the same newly developed struts of tubes and rods.