Post-batching CMA dosing into concrete
First Claim
1. A method for dosing concrete, comprising:
- monitoring the slump, on an automated basis using a processor unit, of a concrete slurry while in a rotatable mixer drum during transit from a mix plant to a construction site to which the concrete slurry is being delivered, the concrete slurry comprising a cement binder, water, aggregate, and clay which, in the absence of a clay mitigation agent, absorbs chemical admixture, and which clay is present in the concrete slurry in an amount sufficient to diminish the dosage efficiency of a cement dispersant or other chemical admixture added into the concrete slurry;
wherein the processor unit(i) measures loss of slump (dS) of the concrete slurry in the rotatable mixer drum over a period of time (t) during transit to obtain a measured dS/dt value,(ii) compares the measured dS/dt value with a threshold dS/dt value stored in a memory location which is accessed by the processor unit, and(iii) detects when the measured dS/dt value meets or exceeds the stored threshold dS/dt value; and
whereupon the processor unit, once the measured dS/dt value meets or exceeds the stored dS/dt threshold value, initiates administration of a controlled dosage of clay mitigation agent (CMA) into the concrete within the rotatable mixer drum during transit, the CMA administered being effective to decrease the dS/dt value as measured by the processor unit.
1 Assignment
0 Petitions
Accused Products
Abstract
Disclosed are dosing methods for mitigating the deleterious effect of clays, which are born or conveyed by sand aggregates, crushed rock, gravel, and other aggregates used in the manufacture of concrete, upon the dosage efficiency of cement dispersants added into concrete. Instead of introducing the entire cement mitigation agent (CMA) into the aggregate material at a quarry or upon batching in the mix plant in a singular, upfront dose, the present invention comprises combining at least 51% and up to 100%, and, most preferably, at least 75% and up to 100%, of the total dosage amount of the CMAs into a given concrete mix batch during the transit portion of the delivery between initial batching at the mix plant and the pour event at the job site.
46 Citations
20 Claims
-
1. A method for dosing concrete, comprising:
-
monitoring the slump, on an automated basis using a processor unit, of a concrete slurry while in a rotatable mixer drum during transit from a mix plant to a construction site to which the concrete slurry is being delivered, the concrete slurry comprising a cement binder, water, aggregate, and clay which, in the absence of a clay mitigation agent, absorbs chemical admixture, and which clay is present in the concrete slurry in an amount sufficient to diminish the dosage efficiency of a cement dispersant or other chemical admixture added into the concrete slurry; wherein the processor unit (i) measures loss of slump (dS) of the concrete slurry in the rotatable mixer drum over a period of time (t) during transit to obtain a measured dS/dt value, (ii) compares the measured dS/dt value with a threshold dS/dt value stored in a memory location which is accessed by the processor unit, and (iii) detects when the measured dS/dt value meets or exceeds the stored threshold dS/dt value; and whereupon the processor unit, once the measured dS/dt value meets or exceeds the stored dS/dt threshold value, initiates administration of a controlled dosage of clay mitigation agent (CMA) into the concrete within the rotatable mixer drum during transit, the CMA administered being effective to decrease the dS/dt value as measured by the processor unit. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification