The construction industry, particularly in the concrete aspect, has made significant stride following the introduction of different admixtures. Combined with the usual ingredients like cement, aggregates, water and other cementitious materials, admixtures such as concrete retarders, water reducers and superplasticiser can greatly increase the strength and durability of the finished concrete outlay.
Flexibility and Workability
Proper cement hydration leads to improve concrete workability. Industry standard set a ratio of between 0.22 and 0.25 water-to-cement for proper cement hydration. However, this ratio reduces workability and flexibility. To allow additional time to work on shaping and modelling the outcome, construction companies practice increasing the water-to-cement ratios by up to 0.60. Adding admixtures to industry standard water-to-cement ratio allows greater flexibility and workability.
Increase in Strength
Increasing the water-to-cement ration, unfortunately, will result in the reduced strength and durability of the concrete while increasing the possibility of shrinkage and cracking problems. Admixtures help address this concern. According to studies and actual ground reports, admixtures helped increase the flexural strength of concrete. This would also result in lesser bleeding of excess water, which proves beneficial for the finishers.
The admixtures are categorised according to the amount of the reduced water. A low-range admixture can reduce water-to-cement ratio by 5%-10% has a slump range of 4-5 inches. A medium-range admixture reduces water-to-cement ratio by 10%-15% a slump range of 5-8 inches and improves workability. Finally, a high-range admixture reduces water-to-cement ratio by as much as 30%, a slump range greater than 8 inches which help produce high-strength and high-performance concrete.
The real benefit of using admixtures cannot be computed by a simple formula of the total cost per cubic yard. It is true that admixtures simply add up to the concrete cost. Yet looking from a different perspective, it increases the value of the finished outlay, which is the most important thing at the end of the day simply because you have another happy client. And a happy client is the biggest investment you can get.