- Building with bricks
Cement is a binder. Similar to flour in a recipe, the purpose of cement is to hold the other materials together. But you can’t just use cement alone. You need the other materials and what you mix with the cement will determine the final product.Cement is made from limestone, calcium, silicon, iron, and aluminum, among other ingredients. This mixture is heated in large kilns to about 2,700°F (1,482°C) to form a product known as clinkers, which roughly resemble marbles. These are ground into a powder and gypsum is added, creating the gray flour-like substance known as cement. When water is added to cement, it triggers a chemical process that allows it to harden.There are many different types of cement, but the type most commonly used in construction is Portland cement.
Concrete is a composite of aggregate (such as sand or gravel), cement, and water. The cement makes up from 10 -15% of the total mass of concrete; the exact proportions vary depending on the type of concrete being made. Aggregate makes up more than 60% of a concrete mix — and up to 80% in some cases. The aggregate gives the concrete its mass, and the water activates the cement holding it all together. What proportions of the mix will determine the strength, resistance to freeze and thaw, workability, and how long it takes to harden.
Because it needs a low water to cement ratio, it is much thinner when mixed, making it difficult to use as a bonding element. Concrete is used in structural projects and is often reinforced with steel rebar to maintain its structural integrity as the soil beneath it settles. It is best used for support, such as beams, walls, or other building foundations.
Mortar is used to hold building materials such as brick or stone together. It is composed of a thick mixture of water, sand, and cement. The water is used to hydrate the cement and hold the mix together. The water to cement ratio is higher in mortar than in concrete in order to form its bonding element. When mixed, it is a much thicker substance than concrete, making it ideal as a glue for building materials like brick.