Surface bonding with epoxy
This question is too long. Sorry. Blame it on brain dumps.
I've grown up with farming where many times you don't have what you need, and have to make do. And later in life, I found out I am Autistic, which explains why it is hard to find engineering positions (I have an M.Eng. in materials science and engineering).
I first grew interested in the materials aspects of building science with Hurricane Katrina. And the earthquake in Haiti made me look at things yet again. I live in NW Alberta, Canada, far away from the US Gulf Coast and Haiti. I have visited a few Caribbean islands in the past. Post Katrina, it bothered me that residents regarded houses as disposable. But, if you live outside the cities, you are lucky if you get good concrete, which certainly lends a lot to the idea that houses are disposable. And this is where I first heard of dry stacked concrete block construction, and surface bonding. Which is a method amenable to vounteer construction.
Haiti came along. They have nothing. Importing anything to rebuild is a drain on the economy. Haiti has the raw materials to make aluminum bronzes, which in many applications are equivalent to steel or stainless steel. Haiti used to have trees, but it has a lot of bagasse now. You can make carbon fibre fabric from wood tar, presumably you can do the same from bagasse tar. You can make epoxy from wood tar, and again presumably bagasse tar would work as well. Concrete block is their preferred method of construction.
So, one could envisage making buildings by dry stacked concrete block, and then apply carbon fibre/epoxy surface bonding to it.
And pretty much anything/epoxy is a stronger surface bonding agent than the surface bonding mortar which is commercial.
I've got a bee in my bonnet about trying to get a volunteer built structure which isn't a house. Yes, a person could probably do it withsurface bonding mortar. But I am stuck on "what if". Epoxy/anything for surface bonding is a moisture barrier. To surface bond any block structure (concrete or other) with epoxy/anything, has 2 vapour barriers on either side of the wall. And they are likely strong barriers.
And this goes against building rules. I am beating myself up to think of some way, to make the one epoxy/anything surface water permeable., on one side, or to find some way to exhaust water from the wall.
The best I have so far (theoretical), is to coat the core of the lowest block with a hydrophobic material (silane?), and then cut into the foundation a narrow groove into which a person lays a wick, to draw water out of the wall as it develops. Maybe a person puts a cage at the bottom to actually make an air gap, but I think just having hydrophobic surfaces is enough.
What is an ugly solution, is to have high heat transfer pipes come from the roof into the top of the cores of the wall. And paint them black. At the top of the pipe, is nominally a ball. If there is excess pressure (nominally from water), the ball gets lifted up to exhaust water. To work well, you want really spherical balls, and nearly perfect mating surfaces.
The silane idea looks more practical to me, but neither seems really practical. Any other ideas?
Totally unrelated. None of the image upload formats allowed are vector (like SVG). For things like line drawings, SVG can be much smaller (especially if compressed) than other formats).
Posted Dec 30, 2012 10:57 PM ET
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