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One cubic meter of concrete equals 2400kgs.

What is concrete?

Concrete is made from 3 ingredients, aggregate, sand and cement. The aggregate is for bulk and the sand fills in the gaps between the aggregate with the cement binding these all together.

The usual mix is 4 parts aggregate, 2 parts sand and 1 part cement. Concrete strength can vary by changing the ratio of the ingredients.

Types of concrete

There are many different variations of concrete.

Standard concrete used for house slabs are usually 20/20, which means 20MPA strength and 20mm aggregate. Other mixes used for slabs include 25/20, 20/10, 32/10, 40/10 up to around 70 or 80 mpa for special slabs. The strength of concrete can vary according to how much water is used to mix the ingredients as well as the amount of cement used.

Exposed concrete

Exposed concrete is concrete with the top layer of paste washed off exposing the aggregate, which is usually different coloured stones as below.

Exposed concrete

Coloured concrete

All concrete can be coloured using colour oxides which may be mixed through the concrete or spread over the concrete when it starts to set.

You can put colour through your concrete and also exposed the aggregate to achieve a unique finish.

Polished concrete

Polished concrete is a special mix so that a high polished finished can be achieved. Coloured aggregate and other items, plus coloured oxide can be mixed through the concrete so that the different colours and items will show through once polished.

History of concrete

Concrete is a construction material made from a mixture of cement, water, sand, and aggregate (such as rocks or gravel). The history of concrete dates back to ancient civilizations, where it was used in the construction of buildings, roads, and other infrastructure.

The ancient Egyptians were some of the first to use concrete in their construction projects, around 2500 BC. They used a mixture of mud and straw to make a crude form of concrete, which they used to build structures such as the pyramids.

In ancient Rome, the Romans developed a more sophisticated form of concrete, which they called “opus caementicium.” This type of concrete was made from a mixture of lime, sand, and water, and was used to build structures such as the Colosseum and aqueducts.

During the Middle Ages, the use of concrete declined, and it was not widely used until the Industrial Revolution in the 18th and 19th centuries. At this time, advances in the production of cement made it possible to produce concrete more cheaply and efficiently.

In the 20th century, concrete became even more widely used in construction due to the development of new types of cement, such as Portland cement, and the use of reinforcing materials, such as steel bars, to increase the strength and durability of concrete structures. Today, concrete is one of the most widely used construction materials in the world, with millions of tons produced every year.

How to lay a concrete slab

What is cement?

Cement is a powdery substance made from a mixture of materials, including:

  1. Limestone: This is the primary component of cement, and is made up of calcium carbonate.
  2. Clay: This is another key ingredient in cement, and is made up of aluminum, silicon, and oxygen.
  3. Gypsum: This is added to the mixture to help regulate the setting time of the cement.
  4. Iron oxide: This is added to the mixture to give cement its reddish color.

To make cement, these materials are ground into a fine powder and then mixed together. The resulting mixture is called “raw cement.” To turn this raw cement into the more familiar, gray powder that is used in construction, the raw cement is heated to a high temperature in a kiln. This process, known as “calcination,” removes excess moisture and causes the raw materials to react chemically, forming a hard, solid substance.

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