How to Add Calcium to a Concrete Mix
Calcium chloride is a very common additive for cement to have, especially in the colder regions of the world. The addition of calcium chloride to cement is done to speed up the time that it takes for the cement to set up and to make the cement capable of bearing a load. The drawback of using calcium chloride is that it is highly corrosive to steel. This means that if steel rebar is used in a project, calcium chloride should not be used.
Determine if your project should use calcium chloride. If you are in a rush for your cement to set up and cure, calcium chloride can be added. However, if you are working with steal rebar or interior support structures, you do not want to add calcium chloride to the mix, as it will corrode the bars and weaken your structure.
Select the calcium chloride product for your project. There are a lot of calcium chloride products that you can add to your cement mix. If you need to meet the requirements of ASTM C494, Type C and ASTM D 98, then a 29 percent liquid calcium chloride mix is a good option.
Calculate how much calcium to add to your concrete mix. This is a very simple calculation. You will generally need to add calcium chloride at a ration of two pounds per 100 pounds of concrete. This means that if you have 2,000 pounds of concrete to pour, you will need two percent of this weight in calcium chloride, which is 40 pounds of calcium chloride.
Start up your concrete mixer and mix your concrete by pouring in the dry mix, water and aggregate. Allow the concrete to mix together until all the components are thoroughly incorporated. Then pour in the liquid calcium chloride. Allow this to mix into your concrete thoroughly. Pour into your concrete form.
- Calcium chloride
- Cement mixer