Styrofoam Swedes
If you hear the words “foam” and “skatepark” together, you’d probably think of one of those tick learning pits, not a skatepark construction. I wouldn’t believe it if someone told me about it, but here are the pictures. Apparently, it’s common practice to use styrofoam (or some kind of poly foam) for fill in skateparks in Sweden. I don’t have any details besides these few pics from Placed to Ride, who were applying the theory to a skatepark in Gothenburg, Sweden. The building blocks can be seen here, and the finished result here. I guess it works. If anyone can explain the how and why, I’m all ears.
funny, i was already considering using some slabs of extruded polystyrene to fill and shape under concrete. Styrofoam as its brandname is known, kinda like Band-aid= medical adhesive strips, is easy to shape and cut. seems like it would be quick and easy to use to build certain forms and shapes for concrete work. but I am curious as to their reasoning for its use, if there is some other unknown factor.
check this out:
http://brusk.be/forum/viewtopic.php?t=36&postdays=0&postorder=asc&start=15
This Pool is in Brussel/Belgium, and its completely build with this Styrofoam Technique…
rad link, thanks
My guess is the backfill doesn’t matter too much. The support for the structure comes strictly from the rebar. Think of how Hailey’s big wall, the one across from the full pipe, was no back fill.
styrofoam and concrete can go hand in hand, a buddy of mine is currently building a basement retaining wall system using a very similar method, in fact the styro forms already have the reinforcements placed inside of them, all he has to do is place the forms and fill with ‘crete.
Oops, Correct link
my guess is that Stefan wouldn’t be doing it if he didn’t think it would work. He’s designed/built more than a couple skateparks. Very nice fellow as well.
It makes sense. There is alot of styrofoam used in new construction now in order to save costs on concrete. Infact there is a grouing number of houses in Portland even that are being constructed using styrofoamwith concrete slurry mixed for the building walls.
I get saving money on concrete, but the foam is being used in cases where it would normally be just a bunch of dirt. My guess (informed via Conahan) is that it might have something more to do with climate.
I’m sure it works. I’m just trying to figure out the why. Seems like a very non-green way to build, so there’s got to be a reason. I guess foam could be cheaper than dirt.
Something else interesting is their use of remesh instead of rebar. Seems like a less expensive material and less labor intensive as far as not having to tie it all together. I wonder if the finished product is necessarily less durable than concrete with rebar. Any engineers reading?
I imagine the styrene has a few advantages, however well packed the fill dirt is it still has to have some moisture permeating in it. With Sweden’s colder than here (being Alabama in this case), with many freeze and thaws in their seasons. Water seepage into the fill as it penetrates the concrete could cause some cracking and collapsing of certain structures. Polystyrene is dense, cold doesn’t affect it, damp doesn’t affect it…
Sounds reasonable to me, but I’m just formulating a hypothesis with my ass, I have no idea.
Less chance of setteling.
They used it on the waterfront condos right by the Broadway bridge for the water feature between the two buildings . Super common , don’t have to tamp it , holds shape . One truck load vs. how many yards of dirt ?
it is used in europe quite a bit, we have recently used it on ledges and shit, but when we built Antwerp, the Brussels park was happening,
you stack it and you cut in with chain saws like cutting an onion. Cost for foam is most often much more than dirt, but sometimes in some locations the right dirt or fill dirt is hard to come by. Especially when it is far away and fuel costs are high.
But for cases like in Brussels, the foam is used to reduce the load weigh of the park. I think that the Brussels park was built on top of some railroad tracks or something…so they had to do this.
we have a bid out to a park out there that is HUGE and all foam… it took lots of discussion to see if we would even touch it.
It makes great sense, rebar reinforced concrete is amazingly strong. It combines the tensile properties of steel (prevents stretching) and the compressive properties of concrete (resists crushing), creating a “strong in all directions” composite material. The structure of the concrete/rebar alone, if you removed the Styrofoam afterwards would be more than strong enough to hold a few skaters and the forces caused by their momentum. It’s only impossible to create a concrete ramp with a void inside because concrete is a fluid that must set.
In summation: it doesn’t matter what is on the inside, unless that material expands/contracts a great deal with temperature. A thick enough layer of concrete/rebar is super strong.
you can build a house like a skatepark with hollow core expanded foam blocks. They are light weight and novice self builders can complete a storey house in a day. Then fill with concrete from a truck. Super insulated and quick, just need to get the manufactures building some transition molds and we could halve the average skate park budget 🙂