While the term "AB brick" is not a standard technical classification, it most likely refers to the common classification of Engineering Bricks into Class A and Class B. These bricks are defined by their performance characteristics rather than their visual appearance.
Understanding Engineering Bricks
Engineering bricks are a type of brick specifically manufactured for high strength and low water absorption. They are used in applications where these properties are critical, such as:
- Below ground level construction
- Damp-proof courses (DPCs)
- Retaining walls
- Manholes
- Other civil engineering works
Unlike standard building bricks, which are often chosen for their aesthetic qualities, engineering bricks are selected purely based on their physical and mechanical properties.
Classification: Class A vs. Class B
Engineering bricks are typically categorized into two classes based on minimum crushing strength and maximum water absorption:
| Characteristic | Class A Engineering Brick | Class B Engineering Brick |
|---|---|---|
| Minimum Crushing Strength | Higher (e.g., > 75 N/mm²) | Lower (e.g., > 50 N/mm²) |
| Maximum Water Absorption | Lower (e.g., < 4.5%) | Higher (e.g., < 7%) |
Note: Specific values can vary slightly depending on regional standards and testing methods.
Class B Engineering Bricks
Based on the provided reference:
The Red Engineering Class B brick made by Wienerberger, is a perforated, wirecut brick that combines both high strength and low water absorption. Engineering bricks are specified for their physical characteristics and not their appearance.
This description highlights the key features of a Class B engineering brick:
- Manufacturing Method: Can be wirecut (cut from a column of clay using wires).
- Structure: Can be perforated (have holes running through them, which can aid firing and bonding).
- Performance: Possess high strength and low water absorption, meeting the required standards for their class.
- Purpose: Chosen for functional properties over aesthetics.
Class B bricks offer a balance of strength and water resistance suitable for many demanding applications where Class A's absolute highest performance isn't necessary, often providing a more cost-effective solution.
Class A Engineering Bricks
While not detailed in the specific reference, Class A bricks represent the highest grade of engineering brick, offering superior strength and even lower water absorption than Class B. They are used in the most demanding structural and civil engineering applications.
In summary, "AB brick" likely refers to the classification system (Class A and Class B) used for engineering bricks, distinguishing them by their critical performance properties.
