Thursday, March 24, 2011

Concrete Benches cast in fabric

Wow, what a while it's been since my last post - well, as for now I've just finished a great workshop with 80 (yes, 80) first year students of architecture and architectural engineering. In a week's time the students had to design and produce a concrete bench: This included designing the formwork principles and building the formwork. Finally the students had to pour the pieces of around 300 liters each (750 kgs of concrete), and finally - strip the formwork and reveal the concrete evidence of the experiments...
[Students pouring the fabric formed concrete bench - and getting advice from the concrete sponsor, Unicon]
Here's an older post with some images of references to benches.

No blow outs
The pieces of this year's workshop weren't super tall - the tallest formwork was 140 cm high. Out of 12 pieces and 4 cubic meters of concrete, we had no blow outs - yipee - this wasn't really the case last year. Formwork pieces were all 2 meters high - and only one student piece survived in its initial state... read more about last years workshop here.

The Clover
Below are some images of the Clover Bench. More info to follow. Enjoy!
['Trekløver', the Clover. Fabric formed concrete bench. Student work at TEK1]
Do I need to say that the focus was on fabric formwork?
Besides being the subject of my research, fabric formwork has great potentials for introducing concrete to students of mostly no previous experience to either pouring or building formwork - in fact building anything yet :)

Formwork tectonics
First of all, building with light weight fabric lets you produce quite large structures just because the weight of the formwork structure is kept down.
More importantly (says the teacher) there's a structural hierarchy in building fabric formwork - an apparent material dialogue to be considered. The material dialogue is between the concrete and the three elements that the formwork is made out of: the frame holding the fabric, the fabric itself, and a restraining method to keep the fabric in tension and control bulges during the pour. 

Formal consequence
When the concrete is poured as an almost ruthless matter the formwork is really put to the test. All choices made during the construction of the formwork results in a direct formal consequence on the form and surface of the concrete.
[Fabric form for the 'Clover' - without the inner form, Student work]

Formwork statics is quite an interesting subject - designing formwork structures the students get a grasp of pure tectonics. Quite simple structural principles may result in striking concrete forms :)

[The funky inner form for the Clover. Students used scrap vinyl flooring to create a smooth surface inside the bench. Student work]

Credits to the members of the Clover team who built the formwork shown above: Alva Altgård, Symra Joner Andbo, Helga Hallgrimsdottir, Rasmus von Wurstemberger Nielsen, Marie Rugholm Nielsen, Andreas Klestrup Hansen. Students study at RDAFA or DTU

The workshop was part of a course held by the Institute of Technology and co-teachers were Johannes Rauff Greisen and Finn Bach


  1. Awesomeness! I look forward to photos of the other benches if they become available.


  2. If you don't blow out, you don't build high enough :)

    Jens U.

  3. True that, Jens - and you would know :) We wanted a higher success rate this year so the pours weren't so high!

  4. Phenominal ! Very nice the fabric form concrete seating... are you in the United States? I am designing a public park and would like to know if these pieces might be available, safe and/or have already been used for public seating... Rsvp Thx _+*

  5. Of course, Denmark... I noted that some work was done in Manitoba, Canada... Might this be doable for a location in New York stat, I wonder_? Rsvp


Note: Only a member of this blog may post a comment.