Chemical admixtures help concrete contractors gain more control over their work and meet customer demands for year-round construction, shorter project completion times, and improved concrete performance. For example, accelerators can be used to shorten set times in cold weather, superplasticizers to improve workability and increase strength, retarders to extend set times, and air-entraining agents to enhance freeze-thaw resistance.
Chemical admixtures are now available to:
- Allow placement of fresh concrete in ambient temperatures as low as 20 degrees
- Stop cement hydration for hours or days, allowing recycling of leftover concrete and truck mixer washwater
- Protect embedded metals in concrete from corrosion
- Enhance finishability
- Enhance the performance of flowable fill
Prepackaged admixtures available from some companies allow easy on-site addition of admixtures. These products come in premeasured doses in water-soluble packages that are simply tossed into the hopper of a ready mix truck.