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Self-amalgamating concrete

Time-saving
  (+6, -1)
(+6, -1)
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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.

8th of 7, Apr 27 2016

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]

How to use self-amalgamating tape http://www.satcure....tech/self_amalg.htm
[Ian Tindale, Apr 29 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?
WcW, Apr 27 2016
  

       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.
bungston, Apr 27 2016
  

       Epoxy?
WcW, Apr 27 2016
  

       Gesundheit !   

       // 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.   

       Anyone ?
8th of 7, Apr 27 2016
  

       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".
FlyingToaster, Apr 27 2016
  

       (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".
normzone, Apr 27 2016
  

       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.
8th of 7, Apr 28 2016
  

       When I was doing ceramic tile in the...previous century, that product was trademarked as "Wonderboard".
normzone, Apr 28 2016
  

       // I mean the theoretical kind //   

       The sort that exists only on paper, as a series of drawings and equations ?
8th of 7, Apr 28 2016
  

       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.
normzone, Apr 28 2016
  

       Take it from us, you're not.
8th of 7, Apr 28 2016
  

       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.
scad mientist, Apr 28 2016
  

       Have you been working at Amazon ?
normzone, Apr 28 2016
  

       Has who been working at Amazon ?
8th of 7, Apr 28 2016
  

       " if this works, it could be an improvement over brick and mortar. — scad mientist, Apr 28 2016 "
normzone, Apr 28 2016
  

       There’s already SAT — self amalgamating tape — for satellite receiver installations. You wrap the f-plug in SAT and in a short while (astronomically speaking) it’ll gloop together into a single weatherproof mass moulded around the f-plug and some of the thing it is plugged into (typically the sockets on the LNB).   

       One would presume it’d only be a minor change to the ingredient list to make SAT into SAC.
Ian Tindale, Apr 29 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.   

       But in principle, yes.
8th of 7, Apr 29 2016
  
      
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