Methods for determining whether an existing concrete composition is overdesigned

Abstract

Design optimization methods can be used to design concrete mixtures having optimized properties, including desired strength and slump at minimal cost. The design optimization methods use a computer-implemented process that is able to design and virtually “test” millions of hypothetical concrete compositions using mathematical algorithms that interrelate a number of variables that affect strength, slump, cost and other desired features. The design optimization procedure utilizes a constant K (or K factor) within Feret's strength equation that varies (e.g., logarithmically) with concrete strength for any given set of raw material inputs and processing equipment. That means that the binding efficiency or effectiveness of hydraulic cement increases with increasing concentration so long as the concrete remains optimized. The knowledge of how the K factor varies with binding efficiency and strength is a powerful tool that can be applied in multiple circumstances. A concrete manufacturing process may include accurately measuring the raw materials to minimize variation between predicted and actual strength, as well as carefully controlling water content throughout the manufacturing and delivery process.

1 . A method of determining whether an existing concrete composition having a given design strength and given ratio of components is overdesigned without having to (i) prepare a concrete test sample, (ii) allow it to harden, (iii) test its actual strength, and (iv) compare the actual strength of the test sample with the given design strength, the method comprising: 
 determining an apparent design K factor for the existing concrete composition based on the given design strength of the concrete composition and the given ratio of components within the concrete composition; and    comparing the apparent design K factor with a more optimal K factor that corresponds to the given design strength and which is selected from among a plurality of different K factors that vary with varying concrete strength.    
   
   
       2 . A method as defined in  claim 1 , further comprising determining how much the existing concrete composition is overdesigned by determining a deviation between the apparent design K factor of the existing concrete composition and the more optimal K factor.  
   
   
       3 . A method as defined in  claim 1 , further comprising identifying a ratio hydraulic cement, water and air for the existing concrete composition, the apparent design K factor being determined based on the ratio hydraulic cement, water and air.  
   
   
       4 . A method as defined in  claim 1 , further comprising using a computing system when determining the apparent design K factor.  
   
   
       5 . A method of determining whether a concrete mix design used in manufacturing a concrete composition having a given design strength and given ratio of components is overdesigned without having to (i) prepare a concrete test sample, (ii) allow it to harden, (iii) test its actual strength, and (iv) compare the actual strength of the test sample with the given design strength, the method comprising: 
 determining an apparent design K factor for the concrete mix design based on the given design strength of the concrete composition and the given ratio of components within the concrete composition; and    comparing the apparent design K factor with a more optimal K factor that corresponds to the given design strength and which is selected from among a plurality of different K factors that vary with varying concrete strength.    
   
   
       6 . A method as defined in  claim 5 , further comprising determining how much the concrete mix design is overdesigned by determining a deviation between the apparent design K factor for the concrete mix design and the more optimal K factor.  
   
   
       7 . A method as defined in  claim 5 , further comprising identifying a ratio hydraulic cement, water and air within concrete manufactured using the concrete mix design, the apparent design K factor being determined based on the ratio hydraulic cement, water and air.  
   
   
       8 . A method as defined in  claim 5 , further comprising using a computing system when determining the apparent design K factor.  
   
   
       9 . A method of determining whether an existing concrete composition having a given design strength is overdesigned without having to (i) prepare a concrete test sample, (ii) allow it to harden, (iii) test its actual strength, and (iv) compare the actual strength of the test sample with the given design strength, the method comprising: 
 selecting an optimal design K factor for an optimal concrete composition in which actual strength approximates or equals the given design strength, wherein the optimal design K factor is selected from among a plurality of different optimal K factors that vary with varying concrete strength;    determining an apparent design K factor for the existing concrete composition based on the given design strength of the concrete composition and a given ratio of hydraulic cement, water and air within a paste fraction of the concrete composition; and    comparing the apparent design K factor with the optimal K factor.    
   
   
       10 . A method as defined in  claim 9 , further comprising determining how much the concrete mix design is overdesigned by determining a deviation between the apparent design K factor of the existing concrete composition and the optimal design K factor.  
   
   
       11 . A method as defined in  claim 9 , further comprising using a computing system when determining the apparent design K factor of the existing concrete composition and comparing the apparent design K factor with the optimal K factor.  
   
   
       12 . A method as defined in  claim 9 , further comprising redesigning the existing concrete composition by means of an optimization procedure that utilizes a revised design K factor that more closely correlates with the optimal K factor for the given design strength than the apparent design K factor, wherein the optimization procedure yields a revised concrete composition having an actual strength that more closely correlates with the design strength compared to the existing concrete composition.  
   
   
       13 . A method as defined in  claim 12 , wherein the existing concrete composition is redesigned using a computing system.  
   
   
       14 . A method as defined in  claim 9 , further comprising: 
 constructing an optimal K factor curve for a given set of raw materials by identifying an optimal K factor point representative of a concrete strength value and then constructing an optimal K factor curve that passes through that point and that is representative of optimal K factors that vary with varying concrete strength; and    selecting the optimal design K factor from the K factor curve.    
   
   
       15 . A method as defined in  claim 9 , further comprising constructing a K factor curve for a concrete manufacturing plant by testing actual strengths of a plurality of properly prepared concrete compositions of the manufacturing plant, determining a K factor for each concrete composition based on the actual strength and ratio of hydraulic cement, water and air in the composition, and plotting the actual K factors versus actual strength so as to construct the K factor curve.  
   
   
       16 . A method of determining whether a concrete mix design used in manufacturing a concrete composition having a given design strength is overdesigned without having to (i) prepare a concrete test sample, (ii) allow it to harden, (iii) test its actual strength, and (iv) compare the actual strength of the test sample with the given design strength, the method comprising: 
 selecting an optimal design K factor for an optimized concrete mix design in which actual strength approximates or equals the given design strength, wherein the optimal design K factor is selected from among a plurality of different optimal K factors that vary with varying concrete strength;    determining an apparent design K factor for the concrete mix design based on the given design strength of the concrete composition and a given ratio of hydraulic cement, water and air within a paste fraction of the concrete composition; and    comparing the apparent design K factor with the optimal K factor.    
   
   
       17 . A method as defined in  claim 16 , further comprising determining how much the concrete mix design is overdesigned by determining a deviation between the apparent design K factor of the concrete mix design and the optimal design K factor.  
   
   
       18 . A method as defined in  claim 16 , further comprising using a computing system when determining the apparent design K factor of the concrete mix design and comparing the apparent design K factor with the optimal K factor.  
   
   
       19 . A method as defined in  claim 16 , further comprising redesigning the concrete mix design by means of a computer-implemented optimization procedure that utilizes a revised design K factor that more closely correlates with the optimal K factor for the given design strength than the apparent design K factor, wherein the optimization procedure yields a revised concrete mix design that yields a concrete composition having an actual strength that more closely correlates with the design strength compared to the existing concrete mix design.  
   
   
       20 . A method as defined in  claim 19 , further comprising: 
 constructing a design K factor curve for a given set of raw materials used to manufacture concrete at a concrete manufacturing plant by identifying one or more design K factor points representative of one or more concrete strength values and then constructing a design K factor curve that passes through the one or more design K factor points and that is representative of design K factors that vary with varying concrete strength; and    selecting the revised design K factor from the design K factor curve.