There are a number of bricks actively available in the construction industry. However, not all the bricks are the same; They vary based on the raw materials used, their qualities, characteristics, and purposes.
Engineering brick is one type that is specially engineered for high-resistance purposes. Here, we take a look at what an engineering brick is, its types, properties, and applications, and how it differs from other bricks.
What is an Engineering Brick?
Engineering bricks are clay bricks that exhibit high strength and high resistance to fire and acid reactions. These bricks are made from high-quality clay, and burnt at high temperatures to withstand high loads, heat, and chemical reactions. These bricks are generally used in structures where strength and load-bearing are crucial. These bricks are also used in underground structures, such as foundations, sewers, and drainage systems.
What are the Properties of Engineering Bricks
Size
Engineering bricks are typically the same size as solid clay bricks. However, they also come in different shapes and sizes for different needs. Some engineering bricks have holes in them, which makes them lighter and better at holding onto adhesives. These size options make engineering bricks suitable for strong structures like foundations and load-bearing walls.
Colour
Engineering bricks are available in two main colours- red and blue. Generally, blue colour bricks are classified as Class A bricks, while red-coloured bricks are classified as Class B. However, red Class A bricks and blue Class B bricks are also available in the market.
Water Absorption
Engineering bricks have low water absorption rates. They won’t be able to absorb water more than 7% of the brick weight, which is lower than other brick types. The high water resistance prevents the structure from moisture, rainfall, and water penetration.
Fire Resistance
These bricks resist fire and other heat waves, as they are dried at high temperatures during the manufacturing process. Their ability to withstand high temperatures makes them ideal for structures requiring fire resistance. With these properties, they are suitable for use in fireplaces, chimneys, and furnaces.
Compressive Strength
These bricks demonstrate higher resistance to compressive loads compared to other clay bricks. Their compressive strength ranges from 75 N/mm² to 125 N/mm², depending on the type and quality of the bricks.
Manufacturing of Engineering Brick
Clay samples are collected and tested to ensure quality, as manufacturing engineering bricks requires clay with high durability. The clay is excavated, cleaned, and blended with sand, water, and additives to form a mixture. This blended clay is then compressed into a homogenous paste and moulded using machines to remove any air gaps. The molded bricks are dried under the sun and then fired at a high temperature in a low-oxygen environment until they achieve high strength and durability.
Types of Engineering Bricks
Engineering bricks are classified into two types based on strength, durability, and resistance.
Class A Bricks
Class A bricks are superior-quality bricks with high strength and resistivity. They have a compressive strength of 125 N/mm² and a low water absorption rate of around 4.5%. These bricks generally appear in blue due to exposure to high temperatures in a low-oxygen environment.
Class B Bricks
Class B bricks have a compressive strength of more than 75 N/mm² and water absorption not exceeding 7%. These bricks are typically red and are priced less than the Class A bricks, making them a preferred option for many applications.
Perforated Engineering Bricks
Engineering bricks are also available in perforated form with holes within the structure. This design could help reduce the overall weight of the structure and help adhesives to hold bricks. These also act as thermal insulators, not allowing the outside weather to affect the room temperature.
Application of Engineering Bricks
Building Foundations
These bricks have high compressive strength and can be used for building foundational structures. Both the Class A and Class B bricks have high compressive strengths, and both can be applicable to construct retaining walls and foundations.
Damp Proof Courses
Engineering bricks have high durability against chemical reactions and abrasion. They can prevent the wall from dampness, effectively preventing moisture and water content on the surface. Their use can protect the exterior structure from dampness under hydrostatic pressure.
Water-exposed Structures
Since Engineering bricks have high water resistance, they can be applied to water-facing structures such as tunnels, canal walls, bridges, pipelines, etc. Both Class A and Class B bricks have low absorption rates, which could help the structure last longer, even in extreme conditions.
What is the Difference Between Engineering Bricks and Facing Bricks?
| Engineering Bricks | Facing Bricks |
| The main purpose of Engineering bricks is to resist heavy loads, high temperatures, and low water absorption rates. | The main purpose of Facing bricks is for aesthetically appealing design. |
| They are typical of standard size and come in either blue or red colour. | Available in various shapes and colours, including red, grey, and black. |
| They have a low water absorption rate, making them suitable for moisture- and water-resistant structures. | They have higher water absorption rates; however, some facing bricks with low water absorption rates are also available and can be used for enhanced durability. |
| They have high compression strength of 75 to 125 N/mm², suitable for load-bearing structures. | Facing bricks have seven to ten times lower compressive strength and are used for low-load-bearing structures and other ornamental uses. |
Conclusion
Choosing the right building materials is essential for any construction process. Every project is aimed to last longer, with security and durability as the key priorities. Engineering bricks provide high strength, durability, and resistance against heat and water, thereby preventing structures from any kind of external hazards. Although there are several brick options available in the market, engineering bricks play an underrated role, as they are mostly used in non-visible structures(such as foundations, sewer systems, and damp-proof courses). The uses of these bricks are vast, and their versatility makes them appealing for any construction project.