Almost 90% of the people out there think that concrete and cement are the same things. In reality, concrete and cement are two different things. Cement is just but a component of concrete. Concrete is made up of three main components. They include;
- Aggregates for example rocks, travels and sand
- Portland cement
On the other hand, cement which is normally available in its powdery state acts as a crucial agent when mixed with water and other aggregates. This mixture is what is referred to as a concrete mix. This combination is then poured and hardened. It results in a very durable material known as concrete.
The Basics of Mixing Concrete
First, let’s learn more about the three components of concrete.
The main aggregate is sand. Small rocks or stones and gravel is what is normally used as the coarse aggregate in most procedures.
- Portland Cement
When cement and water are mixed, they form a paste. This paste is what coats the aggregates and the sand together. The paste later heals and hardens, holding everything together.
Here, water plays a very crucial part. It chemically reacts with cement through a process called hydration to make concrete easy to work with. In this particular industry water/cement ratio ( w/c ratio) is a term used to refer to the amount of water in pounds compared to that of cement in the mix.
To achieve a surface of the highest strength and least permeability or in other terms, a strong and durable concrete, the water/cement ratio should be low.
Properties of Concrete
With concrete, you don’t need help from professionals. Concrete is easy to work with. You can place and consolidate it effortlessly. It’s a good option for DIY projects.
Concrete is very economical. Think about it this way, its quality depends on the water/ cement ratio right? This means that the water ratio to cement should be minimised, in return, this reduces the amount of cement required and in one way or the other the cost is reduced, making concrete a very pocket-friendly material to work with.
Below are a few tricks to help you reduce the amount of water and cement required.
- Go for the aggregate with the largest size of particles
- Use the stiffest mix that there is
- The prime ratio of fine coarse aggregate should be the way forward
Always know the goals and desires that you want to achieve before mixing the materials.
Examples of Concrete Admixtures
Admixtures are other components that are added to the mixture to achieve a certain goal. Examples include;
Accelerators are introduced to concrete to decrease setting time and to also speed up early strength
These types of admixtures are used in areas with hot weather conditions to curb setting time. It can also be used as a water reducer
This is a product used to restore cement in the mix by 15 to 30%. Fly Ash makes the concrete easy to finish, reducing the heat generated and also improves its workability
Air – Entering Admixtures
This is the best option for that type of concrete that is exposed to freezing or thawing conditions. It’s beneficial for it improves the concrete workability and durability
Here is where the secret is, this admixture helps reduce the amount of water needed during the mixing process. In other words, this is what determines whether the end product will be strong or weak. Remember, the lower the w/c ratio the higher the strength.
Concrete can also be reinforced for more stability and durability. It can be reinforced using welded wire mesh or fibres.