Final Assignment: Catenary vault

For my final project, I wanted to work with textiles and gravity, inspired by Gaudi’s studies of self-supporting pillars and vaults. I would like to learn more about catenary – the physical term for the idealized curve, and how it can be used for making vaults. I believe that it now is possible to again use curved vaults in architecture, which have not been so popular for quite some time.

I wanted to make a self-supporting vault, casted upside down. The idea was that by hanging the fabric mould – the concrete would move into the most ideal curve for the vault, and as such be self-supporting. The process is described below:process.jpg

For my prototype I simple stapled two pieces of stretchy jersey fabric together and let them hang, filled with concrete. It seemed to work very well, but the casting had not fully dried in the right picture, so the fabric was not removed.

For the final product a template was made and the jersey fabric cut accordingly. The mould was hanged from each corner of the box and then filled with concrete. By now, I realized that the final product would not be rounded, rather more rectangular. The concrete mixture followed the give recipe for fabric casting, but extra water was added to make the mixture more fluid to fit into the mould.

After three days, the casting was removed from the box. When turned upside-down the casting could luckily support itself. However, it seems as if the casting has broken in the top – where the strain on the mould was the highest and the hole on top was the biggest. As such, the casting is probably in two pieces. Furthermore, it seems as if the concrete has not yet dried as a thin layer of concrete follows when pulling off the fabric. Perhaps in a few days the fabric can be more easily removed.

final product finished

The final product looks good (although with the fabric still on) and is self-supporting. The breaking is most likely due to the fabric mould that probably was too thin in the lowest-hanging parts. The size of the hole on top also plays a big part in the breakage. Had the hole been smaller the breakage might not have occurred. Also – the two pieces of fabric should probably not have been exactly the same size. Rather, the lowest hanging piece should have been larger and as such allow for more concrete further down – strengthening the casting. Perhaps the lower hanging textile could have been a stretchy jersey and the top fabric a more sturdy woven fabric.

casting worked well – had not dried when casting finished product

Finished casting:
Fabric mould had too big of a hole – should be decreased
Mixture had extra water to increase fluidity

Finished casting has not dried – fabric cannot be removed yet
Finished casting has probably broken in two pieces
Structure is self-supporting (yay!)