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Cement vs Concrete

Now that we have had a quick overview of rebar in our previous article I thought taking a look at cement vs concrete and even the difference in mortar within construction would be a great next step. These are words we hear regularly and even at times used interchangeably though they are in fact different things, even if they are closely related.

What is Cement?

Cement is all around us on most days. Many structures require cement as a binding agent, making it an essential material within the construction industry. Cement acts to bind and adhere other materials together when mixed with water, which hardens as it dries, helping to maintain a solid structure. This is that grey powdery substance you get in large bags at the hardware store.

Cement is composed of various ingredients such as: alumina, silica, magnesia, iron oxide, lime, alkalis, sulfur trioxide, and calcium sulphate. Each of these ingredients serve a different purpose. For more details on that have a look at this article on cement ingredients and their functions: Proportion of Cement Ingredients, Their Functions and Limitations

How is Cement made?

The process begins at the mining phase where lime, marl and clay are mined from a quarry. These raw materials are then crushed and mixed together with various minerals. This mix of ingredients are then transported to the kiln where they are heated to temperatures up to 2000℃. Through this process the ingredients are transformed into small granules known as clinker. The clinker is ground together with gypsum (calcium sulphate dihydrate – often used in plaster and drywalling) to create a fine grey powder we call cement.

What is Concrete?

Now when we look at cement vs concrete, knowing what cement is, we can clearly define each of these components. Cement, when mixed with water, becomes a binding agent and is a main ingredient in the mixture of concrete. What this means is that concrete is a mixture of a cement paste (cement and water) and aggregates, such as gravel, sand or crushed stones. Once poured or placed into the desired place the concrete would harden as it dries, often referred to as the curing phase.