Concrete Used in Ancient Rome

A Concrete Fact

Did you know that architects in ancient Rome used concrete to create many durable structures, some of which are still standing.But the recipe for how to make concrete was forgotten for more than a thousand years after the Roman Empire collapsed in the fifteenth century. A British engineer finally rediscovered the formula in 1756, and today concrete is a prime component in many highways, dams, bridges and buildings.

concrete used in ancient roman roads
The Romans became adept at constructing roads, which they called viae. They were intended for carrying material from one location to another. It was permitted to walk or pass and drive cattle, vehicles, or traffic of any description along the path. The viae differed from the many other smaller or rougher roads, bridle-paths, drifts, and tracks. To make the roads the Romans used stones, broken stones mixed with cement and sand, cement mixed with broken tiles, curving stones – so the water could drain, and on the top they used tightly packed paving stones.

The Romans learned that low water content and compaction are the keys to making extremely durable structures like the Pantheon, which still stands after 2,000 years.

What is Roman Concrete?

Roman concrete was a type of concrete used with hydraulic cements that are very similar to today’s Portland cement. This type of concrete hardens because of chemical reactions that occur independently of water elsewhere in the environment. In other words, they can harden even in wet weather. When the anhydrous cement powder mixes with water, it produces non-water-soluble hydrates. For the first time in ancient Rome, concrete structures could be built for use underwater (as for aqueducts).