Using fixed weights of variable ingredients under variable conditions yields a predictable result - a variable product. To avoid problems caused by keeping ingredient weights constant, concrete should be produced to meet performance requirements in accordance with a design formula for the composite mixture. This can be done by applying computer technology. A software system scheduled for release in 1991 allows the producer to store a mixture design formula instead of batch weights in the plant control computer. The mixture design formula is supported by ingredient properties, construction needs, concrete mix performance history, and weather conditions and delivery times. Changes in information within these databases would trigger a mix proportion change.
Software for the mix management system will work on many computer systems. For batch plant control systems operated by MS-DOS-compatible computers, it can run the computer itself. If the batch plant is set up to run under Microsoft windows, the system can run simultaneously with the batch plant program on a 386 computer and concurrently on a 286 AT-compatible computer. For non-MS-DOS-compatible batch plant computers, the mix management system resides in an outside box. With either batch plant control system, the mix management system calculates proportions to meet a mixture design formula, displaying the particle distribution analysis and ingredient weights on the plant controller's screen.