Wear-Resistant Concrete Formulations and Methods for Their Preparation

1) A process for the preparation of a concrete installation, said process comprising the steps of:

• A) creating a concrete mix from components, said components comprising each of the following:
• a) a quantity of dry cement mix, said cement mix characterized by:
• i) a manufacturer suggested water/cement ratio value;
• wherein said suggested ratio falls in the range of from about 3.5 to about 6.5;
• and whereupon combination with b), the water/cement ratio is greater than the value corresponding to about 10% less than the suggested value and not greater than the value corresponding to about 30% greater than the suggested value;
• or
• ii) manufacturer suggested water/cement ratio range, having an upper value and a lower value, and whereupon combination with b) below, the water/cement ratio is greater than the value corresponding to about 10% less than of the lower value and less than the value corresponding to about 30% greater than the upper value;
• or
• iii) an amount such that, whereupon combination with b) below, the water/cement ratio is in the range of from about 0.35 to 0.65;
• b) a quantity of water,
• c) a quantity of amorphous silica in the range of from about 0.1 to about 7.0 ounces per hundredweight of cement in a);
• wherein the average silica particle size is in the range of from 1 to 55 nanometers and/or wherein the surface area of the silica particles is in the range of from about 300 to about 900 m2/g;
• d) a quantity of aggregate and/or a quantity of sand in the range of from about 400 to about 700 wt % bwoc;
• and
• B) wherein the water of b) is added in its entirety or in portions comprising an initial portion, comprising at least about. 20 wt % of the quantity of water, and a tailwater portion;
• wherein the initial portion of water is combined with a) and the components of d) to form a first mix;
• and wherein the amorphous silica is added to a mix comprising a), d) and the initial portion of b) to form a second mix;
• AND
• wherein the tailwater is 1) added to the first mix or 2) added to the second mix;
• or 3) is co-added with the amorphous silica to the first mix, wherein the amorphous silica and the tailwater are, optionally, added optionally intercombined;
• and wherein 1) the first mix is agitated for a time tit prior to the addition of the tailwater, for a time t12 after the addition of the tailwater, and for a time t13 after the addition of the amorphous silica or 2) the second mix is agitated for a time t21 prior to the addition of the amorphous silica, for a time t22 after the addition of the amorphous silica but before the addition of the tailwater, and for a time t23 after the addition of the tailwater;
• or 3) the second mix is agitated for a time t31 prior to co-addition of the amorphous silica and the tailwater, and whereupon the concrete mix is then agitated for a time t32;
• OR
• C) wherein the quantity of water is added to a) and the components of d) to form a mix, whereupon said mix is agitated for a time ta prior to the addition of the amorphous silica, whereupon the concrete mix is then agitated for a time tb;
• wherein, in the satisfaction of the constraints of B) or C), a silica-comprising mixture results from B) or C), said silica-comprising mixture is mixed for a time greater than about 5 minutes, at a mixing speed of at least 7 RPM;
• D) an admixture is added after step B) or step C) to form an admixture-comprising mixture, and said admixture-comprising mixture is mixed, for a total time of at least 3 minutes at one or more speeds greater than about 6 RPM.
• E) pouring the concrete mix of D) to form a concrete installation.