What is the Difference Between Concrete and Mortar

Concrete and mortar are both essential building materials, but they have some key differences. Concrete is a strong, durable mixture of cement, water, sand, and gravel, used for building structures like foundations and roads. Mortar, composed of cement, water, and fine aggregates like sand, is used to bond bricks, stones, and other masonry materials together.

What is the difference between concrete and mortar? Concrete is significantly stronger than mortar.

Key Areas Covered

1. What is Concrete 
      – Definition, Features, Uses
2. What is Mortar
      – Definition, Features, Uses
3. Similarities Between Concrete and Mortar
      – Outline of Common Features
4. Difference Between Concrete and Mortar
      – Comparison of Key Differences
5. FAQ: Concrete and Mortar
      – Frequently Asked Questions

Key Terms

Concrete, Cement, Mortar

What is Concrete

Concrete is a widely used building material made by combining several materials like cement, water, and aggregates. It is a man-made material. When mixed with water, cement undergoes a process called hydration, hardening the mixture into a strong, rock-like form. While wet, it is like moldable clay that can be poured into different shapes, and once set, it transforms into a material that can withstand high pressure. Hence, it is used as the main building material on Earth. From towering skyscrapers to sprawling highways, bridges, and dams, concrete forms the backbone of our modern construction world.

There are other benefits of concrete, too. It is fire-resistant, providing a safety layer in buildings. It is also inexpensive and requires very low maintenance. However, its production does create a significant carbon footprint.

What is Mortar

Mortar is a mixture of lime (calcium oxide), sand, and water. When lime mixes with water, it undergoes a slaking reaction, releasing heat and forming calcium hydroxide (slaked lime). This slaked lime then reacts with carbon dioxide from the air in a process called carbonation. The relevant chemical reactions in the formation of the new compounds are as follows:

CaO (lime) + H₂O (water) → Ca(OH)₂ (slaked lime) + Heat Ca(OH)₂ (slaked lime) + CO₂ (carbon dioxide) → CaCO₃ (calcium carbonate) + H₂O (water)

Calcium carbonate, a strong and stable compound, acts as the binding agent. As water evaporates, the mortar hardens, forming interlocking crystals that bind the bricks or stones together.

The specific type of lime used and the sand-to-lime ratio influence the mortar’s properties. Fat lime mortars, which contain more lime, are more flexible but take longer to cure. Lean mortars, which have more sand, are stronger but less flexible.

Similarities Between Concrete and Mortar

1. Both use cement, sand, and water.
2. They are designed to be strong and long-lasting for use in construction projects.
3. Both concrete and mortar harden through a chemical process called hydration, where the cement reacts with water.

Difference Between Concrete and Mortar

Definition

• Concrete is a building material made by mixing cement, water, sand, and gravel, while mortar is a mixture of cement, water, and fine aggregates such as sand.

Composition

• Mortar has a higher sand-to-cement ratio compared to concrete. Mortar also sometimes includes lime aggregate, which makes it more flexible.

Strength

• Concrete is significantly stronger than mortar.

Consistency

• Mortar has a thicker, creamier consistency for easier spreading between bricks. Concrete has a less workable consistency due to the presence of larger aggregates.

Conclusion

In conclusion, concrete and mortar are both essential construction materials, but they serve different purposes. Concrete, a stronger mix with coarse aggregates, forms the foundation of structures. Mortar, containing lime for flexibility, acts as the glue between bricks and stones. While their compositions share similarities, the main difference between concrete and mortar lies in their ratios and the presence of lime in mortar.

FAQ: Concrete and Mortar

1. What is the difference between the composition of cement and mortar?

Cement is a dry, fine powder composed primarily of limestone, clay, and other minerals. Mortar, on the other hand, is a mixture of cement, sand, and water. The sand adds bulk and reduces cracking, making mortar more workable for laying bricks or stone.

2. What is more durable than mortar?

Concrete is basically a stronger version of mortar, achieved by adding gravel or crushed rock to the mix. This creates a denser, stronger material that can withstand heavier loads and harsher environmental conditions.

3. What are the materials stronger than mortar?

Graphene, carbon nanotubes, titanium alloys, and ultra-high-performance concrete (UHPC) are four times stronger than traditional concrete.

4. Why is concrete better?

Concrete is a superior building material due to its strength, durability, and versatility. It can be molded into various shapes and sizes. Unlike wood or metal, concrete doesn’t burn, rust, or rot, making it incredibly resistant to the elements. Even in extreme weather conditions, it stands strong.

5. Which is cheaper, concrete or cement?

Cement is cheaper than concrete. However, cement is a component of concrete, which also includes sand, gravel, and water. Because concrete requires additional materials and labor to make, it usually costs more than just buying cement.

Reference:

1. “Concrete Building Material.” Encyclopedia Britannica.
2. “Chemical Composition of Mortar.” Research Gate.

Image Courtesy:

1. “Gray Concrete Pillars” (CC0) via Pexels
2. “Surfaces brick wall with mortar closeup view” By Tomwsulcer – Own work (CC0) via Commons Wikimedia