h a l f b a k e r yTip your server.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Please log in.
Before you can vote, you need to register.
Please log in or create an account.
|
BorgCo concrete looks like regular concrete, but with a special blend of additives.
When pre-cast into blocks, it can be assembled by spraying both faces of the joint with an aqueous solution of activator which makes the surfaces "sticky". The blocks are then pressed together, and as the activator
oxidises the concrete re-sets to be as strong as the original parent material.
No need for mortar, just a quick spray and assembly to give a strong, permanent, waterproof joint.
Concrete cloth
http://www.concretecanvas.com/ [2 fries shy of a happy meal, Apr 28 2016]
Castle Crete.
https://www.youtube...watch?v=gMMsfVBaaDc [2 fries shy of a happy meal, Apr 28 2016]
Self-"healing" concrete
http://www.cnn.com/...rete-delft-jonkers/ bacteria + water = concrete [jutta, May 01 2016]
Keyed Bricks
Keyed_20Bricks Maybe just the right bricks to use with this... [Custardguts, May 03 2016]
[link]
|
|
Which ingredient are you hoping will oxidize and thus become sticky? How do you see this condition bonding together two similar materials? With no overlapping aggregate or metal reinforcement wouldn't this joint still be a fracture point? What about the need for almost perfect fitment? |
|
|
By sticky, you mean the concrete turns back to mush? I am not sure more water under any circumstances will accomplish this. I think you would have to bake the water of hydration back off. |
|
|
// oxidize and thus become sticky? // |
|
|
No, the activator oxidises and the concrete then stops being sticky. Please, do try to keep up. |
|
|
// How do you see this condition bonding together two similar materials? // |
|
|
It's solvent welding. Not a new concept. |
|
|
// With no overlapping aggregate or metal reinforcement wouldn't this joint still be a fracture point? // |
|
|
Yes... so, totally unlike the mortar joints in brickwork or blockwork, which of course invariably fail in the solid rather than staircase cracking through the courses.... |
|
|
// What about the need for almost perfect fitment? // |
|
|
... like in a stretcher-bond brick wall laid with hammered engineering brick ? Perhaps we're not proposing a completely new masonry technique after all. |
|
|
// more water under any circumstances will accomplish this. // |
|
|
No, it won't. The activator is an aqueous solution. It isn't the water that causes the stickiness. It's just a convenient solvent. |
|
|
// I think you would have to bake the water of hydration back off. // |
|
|
No, because of the additive in the original mix that allows the activator to temporarily make the surface sticky again. |
|
|
Hands up anyone in the class that actually read and understood the idea. |
|
|
I understood the words, individually. The problems come with fitment. |
|
|
Are you talking blocks made from cement ? "concrete" is an aggregate: surfaces aren't smooth, thus "mortar". |
|
|
(raises hand) "Yes...and the detailed explanation of how you WANT it to work rescues it from the realm of (pure) magic, but I suspect we're going to need a chemist". |
|
|
"No, I'm not ill, I mean the theoretical kind". |
|
|
hmmm... individual blocks could have attached to them a layer of concrete cloth, [link], which when activated by water and pressed together would adhere to each other and form a sealed bond. |
|
|
I like it. ...and as an added bonus, here's a [link] of a somebody 3D printing a concrete castle for his kids. |
|
|
// surfaces aren't smooth, thus "mortar". // |
|
|
Concrete blocks cast in formwork have very smooth surfaces; individual pieces of aggregate may be visible, but don't have an effect. This innovation is based on using precast blocks. |
|
|
The concrete cloth idea is good, particularly when the cloth is glass fibre, but the idea is to produce a more homogeneous join. |
|
|
When I was doing ceramic tile in the...previous century, that product was trademarked as "Wonderboard". |
|
|
// I mean the theoretical kind // |
|
|
The sort that exists only on paper, as a series of drawings and
equations ? |
|
|
I dropped out of chemistry class (which is one of the reasons why I come here), so I'm not sure I'm qualified to answer that question. |
|
|
Take it from us, you're not. |
|
|
Regardless of the chemistry (no my strong suit) I think you
will likely still have a weak spot. You're making the
mating surfaces very smooth with your forms. That
means that there are no pieces of aggregate crossing
that plane. Therefore in order to shear the concrete at
that point you only have to break the cement (cement in
the general sense, not necessarily Portland cement if
you're using an alternate chemistry). Shearing the
concrete at only other location would require shearing
pieces of aggregate or breaking the cement in a non-flat
plane which has a larger surface area. |
|
|
Now if you have a cement that sets up into a material
more durable than the aggregate, then it could be just as
strong. |
|
|
Regardless, if this works, it could be an improvement
over brick and mortar. |
|
|
Have you been working at Amazon ? |
|
|
Has who been working at Amazon ? |
|
|
" if this works, it could be an improvement over brick and mortar.
scad mientist, Apr 28 2016 " |
|
|
Well, since SAT is organic solvent/polymer based, and SAC is an aqueous/ceramic system, the minor change would be as simple as changing every single ingredient for a different one. |
|
| |