Samovosstavnovlenie possible because the material is able to bend and form only small cracks and breaks are not wide, as is the case with traditional concrete.
«It's like you're a little scratched hand and scratch soon heal itself.But if you have a large wound that may need stitches even.
We have created the material on which it formed small scratches that heal themselves.Even if you exceed the load on it, the crack will still small, "- says Victor Li, professor at the University.
«To our surprise, we found that under stress after a self-healing material has the same strength, which it had in its original condition," - he said.- "The material can be damaged, but will continue to bear a load.
engineers have found that a crack should not exceed 150 micrometers in width, and for complete regeneration - 50 micrometers.To achieve this, Li and his colleagues improved flexible composite cement on the formula that works for 15 years.
With more flexible than traditional concrete, cement composite behaves
contrast, bends without breaking, and is stiffened by special fibers, which give it strength.It retains its shape and is safe for use in the relative tensile reached 5%, while the traditional concrete crumbles at a relative elongation of 0.01%.
The average width of the cracks in the new concrete is equal to 60 micrometers, which is about half the width of a human hair.Technology is that dry cement cracked surface is capable to react with water and carbon dioxide to form cracks on "scars" with calcium carbonate.Calcium carbonate - a strong connection to nature contained in seashells.
Currently reinforced concrete constructions reinforcement steel to reduce the fracture as possible.But they are small enough to self-healing, and offer access to water and salts to metal, leading to corrosion, which further weakens the structure.
New resettable concrete requires no valves to keep the minimum width of the cracks, and therefore prevents corrosion.
At the moment, the University of Michigan officials are looking for manufacturers who can help advance their technology to market.