Formation of concrete

This idea isn’t as far-fetched as it may seem.It boils down to an understanding of how concrete forms,and how to exploit that process to our benefit. Concrete is a combination of coarse stone and sand particles, called aggregates,that mix with cement, a powdered blend of clay and limestone.When water gets added to this mix,the cement forms a paste and coats the aggregates, quickly hardening through a chemical reaction called hydration.