Concrete and Cement: What’s the Difference?

March 6, 2013

On an almost daily basis, we encounter “facts” and phrases that have been passed off as truth for generations. For example: the red stuff in meat isn’t actually blood; goldfish have a memory far longer than three seconds; the Great Wall of China isn’t actually visible from the moon; Thomas Edison didn’t invent the light bulb; and so on. The BBC comedy panel show QI is almost entirely based around dispelling these types of common misconceptions.

Another regularly heard fallacy regards the assumption that concrete and cement are essentially the same thing. Not only is this not true, it could actually lead to some pretty poor road surfacing if the two are confused! Here’s a handy guide to help you learn the differences between the two…

Cement:

Simply put, cement is an ingredient often found in concrete. This is a basic way of separating the two, but, on a more complex level, cement can be used in a variety of situations depending on its type.

There are two main categories of cement: hydraulic and non-hydraulic. Hydraulic mixes harden through hydration, reacting chemically with water, which makes them ideal for use as mortar on buildings exposed to wet weather or in contact with moisture on a regular basis, such as harbour walls. Hydraulic cement is also used to strengthen concrete, with Portland cement the most popular type.

Portland is not a brand name, but a commonly used strand of concrete, similar to how some steel is stainless and some silver is sterling. Not all hydraulic cement is Portland cement however, with other varieties such as pozzolan-lime, slag-lime and supersulfated cements providing alternatives.

Non-hydraulic cements require dryness to solidify, and often comes in the form of gypsum or plaster. For this reason, non-hydraulic cement is often used for internal purposes, such as coatings for walls and ceilings.

Concrete:

One of the most common and robust materials in the construction industry, concrete is mainly a composite of a paste made from cement (around 10% to 15%) and water with some form of aggregate.

Concrete is used in the building of a huge variety of structures, from walls to roads; bridges to reservoirs, with different types available for different purposes. Variations usually concern the nature of the aggregate used in the production of the concrete, with options ranging from sand and crushed stone to natural gravel and decorative glass or quartzite for a stylish finish.

Once laid, most concrete will require a significant drying time, while simultaneously being kept moist. This control over temperature and moisture during this period – usually between one and two weeks – is known as the ‘curing’ of concrete, and is crucial to its longevity and durability.

Concrete has been used in the construction of many of the world’s modern landmarks, from the Hoover Dam to the Panama Canal, with the largest concrete structure in the world being the Three Gorges Dam in China. Taking 10,000 workers 17 years to build, and contains somewhere in the region of 27.2 million cubic meters of concrete!

Roadmaster Concrete Mixers:

Here at Roadmaster, we supply concrete mixing and transportation options 24 hours a day, 7 days a week, and our range of industry leading volumetric concrete mixers allows for efficient and cost-effective on-site production of concrete in all situations.

Our experienced and friendly staff are on hand to advise you on the concrete mixer most suited to your needs, and we even manufacture a range of vehicles for sale at highly competitive prices. For more information, or to discuss a quote for any of our products or services, don’t hesitate to get in touch and speak to a member of our team today.