The moisture condition of aggregates in concrete is very important – the water-cement ratio controls the pore volume and pore sizes in the concrete, thereby determining not only the strength but also durability.
If the moisture content of wet aggregate is not compensated for, the slump may be too high and the water to cement ratio won’t conform to the mixture requirement. No, it isn’t enough to just add more sand to the mix in hopes that the quality of the concrete will turn out the way the customer requested. The aggregate moisture must always be measured and the amount of batch water adjusted accordingly.
Loads that are not produced at the desired slump can result in additional costs and potentially damaged reputations from angry customers. Companies spend millions of dollars on equipment to produce concrete but miss the underlying control of water and its effect on the material. The proper amount of water stabilizes the strength, the bleed water, finishing effort, and set time characteristics of the concrete. Significant savings in cement, color and admixtures, as well as reductions in the number of wasted batches are all common benefits of moisture measurement.
The Precisions Water System (PWS) is Command Alkon’s solution to combat the issues that excess moisture in aggregates can have on the quality of concrete. With PWS, ready mix producers can eliminate wet loads, keep a history of moisture samples and bake-out pairs, reduce in yard time, and avert risk and waste. With the Precision Water System you can be on your way to more consistent loads, better yield management, lower costs, and more satisfied customers.
Having a system that measures moisture in aggregates will result in concrete that is much more predictable, that will finish properly, and meet the requirements of the contractor and the finished project.