The Wonderful World of Concrete

1. The Wonderful World of Concrete Modern Materials Technology Mr. Ford

2. BACKBONE OF CONSTRUCTION • Concrete and Concrete products are the basis for most building and structural projects • Some components are made on location and others are made elsewhere and brought to the job

3. The Concrete Recipe • Crush some limestone into a fine powder • Heat to about 2700 degrees • The powdered cement is super dry • Mix it with clean sand or stones called an “Aggregate” • Add water and mix • The hardening is called “Hydration”

4. The Chemistry of ConcreteorHow Does It Work? • The Limestone Powder is very small and very dry like flour • When it mixes with the “Aggregate” and water it swells around the small particles and reforms a rock-like substance holding the sand and stone in place • The water causes chemical reaction to the powdered cement and it “Hydrates” into a solid substance

5. “Time to Pour the Batch” • Once mixed it must be constantly stirred so it does not harden • It is transported in special trucks to the job-site • It is then poured into special containers called “FORMS”

6. Shape It • The forms hold the wet concrete in place while it hardens • The surface can also be smooth while it is still in a mud-like state • This work is done in a hurry before it hardens, “nobody takes a break at this time”

7. Later………… • It may take 1 day or up to a week for the concrete to fully harden • The forms are then removed leaving the concrete structure

8. Building With Blocks • Concrete can be made in smaller parts and transported to the construction site • The parts are stuck together using a wet concrete called “mortar”.It acts like glue and the blocks are assembled like a giant LEGO set

9. Structures and Surfaces • Concrete is used for buildings, roads and many projects that require strength and durability • It is available in most places and has a low cost

10. Concrete has many uses

11. What would you make??