Reinforcing filaments or fibers, such as aromatic polyamide (aramid) fibers, can be reliably measured and consistently mixed into asphalt cement concrete by soaking the fibers in a wetting agent, then severing them to a desired length, and mixing the segments with other ACC ingredients. The wetting agent holds the fibers together loosely, so they can be distributed more uniformly throughout the ACC without clumping. The wetting agent soaks into the ACC mixture and/or evaporates, leaving the reinforcing fibers behind.

A concrete slab system includes a bed of a first concrete having a top surface and edge surfaces. The bed's top surface has shrinkage cracks and induced cracks. The widths of the induced cracks are greater than widths of the shrinkage cracks. Non-concrete material is disposed on the bed's top surface and on each of the bed's edge surfaces. A second concrete covers the non-concrete material and the bed. The second concrete has stretchable fibers mixed therein.

A concrete slab system includes a bed of a first concrete having a top surface and edge surfaces. The bed's top surface has shrinkage cracks and induced cracks. The widths of the induced cracks are greater than widths of the shrinkage cracks. Non-concrete material is disposed on the bed's top surface and on each of the bed's edge surfaces. A second concrete covers the non-concrete material and the bed. The second concrete has stretchable fibers mixed therein.

A concrete slab system includes a bed of a first concrete having a top surface and edge surfaces. The bed's top surface has shrinkage cracks and induced cracks. The widths of the induced cracks are greater than widths of the shrinkage cracks. Non-concrete material is disposed on the bed's top surface and on each of the bed's edge surfaces. A second concrete covers the non-concrete material and the bed. The second concrete has stretchable fibers mixed therein.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.

Provided herein are compositions, methods, and systems comprising vaterite and magnesium oxide.

This application relates to making magnesium oxychloride boards. A magnesium oxychloride slurry is mixed by directing magnesium chloride, magnesium oxide, at least one phosphate, at least one inorganic salt, and water into a mixer and mixing these ingredients together to form a slurry. At least one filler is then mixed with the slurry. The slurry is directed to a mold. The mold is formed with the slurry to form a magnesium oxychloride board. The magnesium oxychloride board is then cured.

This application relates to making magnesium oxychloride boards. A magnesium oxychloride slurry is mixed by directing magnesium chloride, magnesium oxide, at least one phosphate, at least one inorganic salt, and water into a mixer and mixing these ingredients together to form a slurry. At least one filler is then mixed with the slurry. The slurry is directed to a mold. The mold is formed with the slurry to form a magnesium oxychloride board. The magnesium oxychloride board is then cured.

Provided is a cement composition that has high fluidity (for example, a 0-drop flow value of 200 mm or more) before curing and exhibits high compressive strength (for example, 320 N/mm.sup.2 or more) after curing. The cement composition includes a cement, a silica fume having a BET specific surface area of from 10 m.sup.2/g to 25 m.sup.2/g, an inorganic powder having a 50% cumulative particle size of from 0.8 μm to 5 μm, a fine aggregate having a maximum particle size of 1.2 mm or less, a water reducing agent, an antifoaming agent, and water. The ratio of the cement is from 55 vol % to 65 vol %, the ratio of the silica fume is from 5 vol % to 25 vol %, and the ratio of the inorganic powder is from 15 vol % to 35 vol % in the total amount of 100 vol % of the cement, the silica fume, and the inorganic powder.

Disclosed herein is a fiber reinforced cementitious composition comprising a cementitious binder and at least one synthetic inorganic reinforcing fiber type, wherein the synthetic inorganic reinforcing fiber type comprises at least one of a man-made mineral fiber type such as basalt fibers, an aluminosilicate wool fiber type or an alkaline earth silicate wool fiber type.