What is Concrete?


From sidewalks and highways to swimming pools and dams, concrete makes up the building blocks of our society. For thousands of years, this man-made material has been a construction staple across the world. But what exactly is concrete? Let’s dive deeper into one of the most important construction materials out there.


The History of Concrete

The earliest known use of concrete dates back all the way to 6,500 B.C. in modern-day Syria and Jordan. Almost every civilization had its own version of concrete in the following centuries, and by 200 B.C., the Roman empire had perfected the recipe for concrete. But as their empire fell, the recipe for concrete was lost to the western world.

It wasn’t until the 1700s that concrete rose in popularity again. The rising interest in science, mixed with the industrial growth of that period sparked scientists and engineers to experiment and find the perfect cement and concrete recipe. Portland cement and hydraulic lime were both developed during this era and continue to be construction favorites. Many famous historical buildings and structures were in fact built with concrete, such as the Pantheon, the Colosseum, and more recently, the Hoover Dam. Today, concrete is a staple in almost every building and construction job.


Why Concrete Is Important

So what makes concrete a construction worker’s go-to material? Its versatility, strength under extreme weight and conditions, and because it’s inexpensive to produce in large quantities have made it a necessity for most building projects. Depending on its use and mixture, concrete can withstand up to 15 thousand psi of pressure. And since the ready-mix concrete industry is projected to surpass $600 billion in revenue by 2025, concrete will continue to hold its place in the construction industry for years to come.

Other qualities of concrete that make it a popular building material is its resistance to freezing and thawing, low permeability (resistant to water seeping in), resistance to wear, and that it’s easy for workers to handle and place properly.


Concrete Composition

At its core, concrete is made of just five ingredients: cement, water, sand, gravel, and air. Most concrete mixes have a specific ratio of each ingredient often referred to as the 10-20-30-40 rule. The mixture will change depending on what the concrete will be used for, but most mixes are made using the ratio of 10 percent cement, 20 percent air and water, 30 percent sand, and 40 percent gravel.

First, the cement is prepared (usually Portland cement). The cement is used as the glue of the entire mixture, binding everything together when it hardens. Next, water and the rest of the ingredients called the aggregates (rock, sand, or gravel) are mixed into the cement paste. Once everything is combined, it’s ready to be used for most projects.

Even though concrete is strong on its own, rods or steel mesh are often placed into molds before the mixture is poured for additional structural reinforcement. 

It’s important to note that concrete and cement—while often used interchangeably—are different. Cement is simply a component of concrete. Depending on construction needs, you’ll use either a hydraulic or a non-hydraulic cement for your mixture. Because of its quick dry time and ability to harden underwater, hydraulic cement is preferred for both minor repairs and large construction jobs.


Concrete Usage: Traditional Construction

Concrete is the most widely used construction material in the world for industrial, commercial, and residential projects. Its applications span from home improvement projects like patios, basements, and swimming pools, to large commercial endeavors like power plants, mining operations, and even Space Ports. Essentially, almost every building and operation today has a concrete component or foundation. 


Concrete Usage: Industrial Aesthetic & Design

Usually, concrete has only been used to provide structure and foundation for buildings and other large-scale projects. But recently, concrete has become a fashionable option for interior designers. The modern industrial aesthetic uses polished or semi-matt finishes on interior walls, floors, kitchen tops, and other furnishings to create a room focused on construction elements. These projects can often be done using a small crew or as a DIY home improvement project. 


The Future of Concrete

The concrete industry is constantly evolving. Most notably, engineers are currently looking to improve concrete by making it more environmentally-friendly. Sustainable construction is an emerging field for companies looking to decrease their carbon footprint and lower CO2 emissions, which quickly mount up due to the high amounts of concrete being created every day. Concrete has even found its way into space. Scientists and engineers are looking to use concrete for future colony construction, which will require research into how different gravity levels and aggregates affect concrete’s strength and durability. 


Concrete Maintenance

Even though concrete requires little upkeep, properly maintaining concrete can increase its lifetime, preserve its polished appearance, and help protect your financial investment. For decorative concrete like polished concrete floors, patios, or driveways, properly maintaining the surfaces will extend its lifetime. Basic maintenance for both decorative and functional concrete surfaces includes:

  • Cleaning the surface of spills, debris, rust, stains, or other build-ups. 
  • Properly sealing the concrete surface and joints to repel water, stop weeds from sprouting through, and provide resistance to daily use. 
  • Proactively sealing small cracks before water or debris gets in and the concrete becomes structurally unsound. 

While many minor fixes can be done on your own, some repairs require expert attention. A-Core’s experience in the concrete industry makes us the perfect people to call for any concrete project. Our concrete specialists can help you with your residential, governmental, or commercial needs. Request a quote for your concrete project today.