Bamboo Roof Structure for Open Architecture Challenge
-
Remus,
It's pretty tedious cutting the cylinders and drilling the holes but if you had the right tools and jigs it could go really fast. Putting the cylinders together with the wire ties goes quickly and is kinda fun.
Fred
-
The honeycomb structure grows...
The first image shows one 10' tube's worth of 2.5" high cylinders. It took approximately 220 wire ties to connect the pieces. I'm going to increase the size to 36" on each side of the triangle. This is about the size of the triangular space I'm envisioning using for the underlying TIN support structure.
The second image shows the good curvature capabilities of the structure.
Does anyone have a good reference for the various flavors of expanding foam/glue?
-
I finished up the first stage of the first honeycomb structure prototype this evening. It incorporates about 19' of 2" diameter PVC tube cut into 2.5" lengths.
I've become quite attached to the thing, which isn't at all surprising given the hours it took to produce. The next stages are to secure it to an underlying triangular frame, tighten up the wire ties, and then "inject" foam into the interstices.
I stopped by "the home center" again today on the way home from work and picked up more wire ties and a 10' x 4" diameter PVC drainage pipe. The 4" pipe should work better than the 2" for my purposes. It will certainly cover space more easily and rapidly and with less weight.
-
It almost looks like you could forget the frame entirely. Just make a dome out of the bondaged tubes. It also looks like after the foam is injected you could parge the outside of the dome. All those hairy ties would attach the parging to the structure.
On the otherhand the dome without any foam or covering would still be a very interesting structure. I can imagine the light filtering in through the tubes & ties. The coloured ties have become a feature. Now imagine how this would look if you built an entire dome using glow-in-the-dark ties! It would be a thing of even greater beauty. As a landscape element it would also look pretty cool at night with an interior light (say a colour-cycling LED?) flowing out through all the tubes/ties.
-
Ross,
Great ideas!
I agree about perhaps not needing a frame for smaller structures. It would be interesting to try a dome as a group project. Cost of the materials would be only a few hundred bucks. Connecting the pieces with the wire ties goes fairly quickly. However, the hole drilling is quite time consuming.
Lighting, especially colored lighting, could be really interesting because of the reflective white PVC. I'll do some experiments tonight. I moved "the thing" up into the living room where it has the very temporary status of abstract sculpture... my wife's a good sport.
I had to Google "parge" to find the meaning. Always nice to add a new word. The parge idea potentially solves a problem I've been pondering, which is how to put a fire-resistant coating on the inside of the honeycomb. I read somewhere that insulating foam needs to be covered with some material that is relatively inflammable and a parge might be the ticket.
Fred
-
2" vs 4" PVC pipe comparison.
The images tell most of the story. The 4" pipe is a much more viable option for doing something like a roof simply much more space is covered with much less material and effort.
-
Completed the 4" diameter tube sections triangle this evening. Used only one 10' tube. Sections are 2" high. I think it would be worth exploring 6" diameter tubes if they are available. This weekend I'll work on injecting foam into the interstices. I'm quite curious how stable the honeycomb will be with hardened foam between the cylinders. Stay tuned.
-
Do you know"La fievre d'Urbicande" (Urbicande fever)
Try this site about Urbicande by Schuiten & Peters
(there is an Introduction in English middle of the page then click red triangles to the end for understand the proliferation
Seems you are the brother of Eugene Robick
little movie about Urbicande City -
Pilou,
Thanks for sharing the links. The Urbicande City movie is amazing. What an imagination... and what talent to make it come alive.
Fred
-
Latest developments...
I injected the foam yesterday evening and the results are good but not great. The essential problem is that the cured foam is not dense enough and compresses under pressure, which in turn allows the whole structure to deflect heavily. The good news is that the honeycomb structure is quite strong even given this. I layed a 1/16" plastic sheet on top of the honeycomb and inched my (210 lbs) way out to the center of the triangle (see image below) and although the surface deflected it held up and recovered nicely after I stepped off.
The foam, in addition to being structurally inadequate, is very hard to control. I'm looking for alternative materials to use in the interstices between the PVC sections. I'm leaning towards trying epoxy next but am open to other suggestions. An ideal material would be inexpensive, easy to apply, and cure really hard.
BTW, I also learned not to over tighten the wire ties before injecting the foam as it makes it very hard to form the honeycomb into curves.
Advertisement