The Concrete Handbook

History of Concrete

Its history dates back thousands of years to ancient civilizations like the Egyptians, who used early forms of concrete to build monumental structures such as the pyramids. The Romans advanced its use, creating enduring structures like the Colosseum, aqueducts, and the Pantheon, the latter featuring the world’s largest unreinforced concrete dome, still a marvel of engineering today.

In the 18th century, the discovery of Portland cement revolutionized concrete production, enabling the material to become stronger and more durable. By the 20th century, reinforced concrete transformed construction, leading to iconic structures like the Hoover Dam.

Today, concrete is at the heart of modern infrastructure—building cities, bridges, tunnels, and highways that connect the world. From towering skyscrapers like the Burj Khalifa to renewable energy foundations for wind farms, concrete continues to adapt to the needs of a changing world while remaining a pillar of durability and innovation.

At its core, concrete is a composite material made up of cement, water, and aggregates. Cement and water combine to form a paste, which coats the aggregates and binds them together as the mixture hardens. The process begins with carefully measured raw materials being mixed, transported, placed into forms, and then cured, transforming into a solid, durable structure.

Quick Breakdown

This simple blend of materials, when properly proportioned, creates one of the most durable and adaptable substances ever invented.

• Cement is the "glue" that binds everything together, most commonly Portland cement. It’s a fine powder made by heating limestone and other materials to high temperatures and then grinding them.
• Water activates the cement, starting the chemical process called hydration. This is what transforms the mix into a solid, durable material.
• Aggregates are the rocks, sand, or gravel that make up the bulk of the concrete. They provide volume, strength, and stability.
• Air is either entrapped or intentionally entrained air bubbles improve durability, especially in freeze-thaw conditions.
• Admixtures are added to enhance performance. For example, plasticizers improve workability, and accelerators speed up setting time.
• Supplementary Cementitious Materials (SCMs) are materials like fly ash, slag, or silica fume can partially replace cement to improve durability, reduce costs, and lower environmental impact.

Visit Ingredients for more information.

How Concrete Works

Concrete’s strength and durability come from a series of chemical and physical processes that begin the moment its components are mixed.
Understanding these stages is crucial to achieving the desired performance and longevity of the material.

Setting - the initial reaction
When cement and water come into contact, they initiate a chemical process called hydration. During this stage, the mixture transitions from a fluid state to a semi-solid, setting the shape and structure of the concrete. This reaction is relatively quick, typically occurring within a few hours, and is influenced by factors like temperature, water-to-cement ratio, and the presence of admixtures.
Visit Essential Properties for more information.

Curing - ensuring durability
Proper curing is essential to maximize concrete's strength and durability. This involves maintaining adequate moisture and temperature during the hardening phase to prevent premature drying, cracking, or shrinkage.
Visit Field Practices for more information.

Hardening - developing strength over time
After setting, concrete enters its hardening phase, where the chemical reactions continue for days, weeks, or even years. This is when the long-term strength of concrete is developed as hydration progresses. The rate of hardening can be influenced by curing conditions, mix design, and environmental factors, but the process results in a material capable of withstanding immense loads and stresses.