1.7: Brick Durability, Strength, and Appearance

Brick durability, strength, and appearance are crucial factors in construction, influencing the choice of bricks for specific applications. The process of freeze-thaw, for instance, significantly affects brick durability. This phenomenon occurs when water absorbed by a brick expands as it freezes, potentially causing damage when it melts and refreezes. Bricks are graded for durability: SW-grade bricks are the most durable, offering high strength and low water absorption, followed by MW-grade and NW-grade bricks.

The strength of bricks is generally quantified by their ability to withstand compressive forces, with typical values ranging from 1500 to 3000 pounds per square inch. This strength is not only a measure of the bricks themselves but also depends on the quality of the mortar used, any reinforcement added, and the overall integrity of the masonry.

The appearance of bricks can vary widely and is affected by several factors. Changes in size and shape and visible damage, such as chips on the face or corners of the brick, impact both aesthetic and functional qualities. For facing bricks and hollow bricks, the extent of chippage is particularly important, as these bricks are often used where visual appeal is a priority.

The color of bricks is primarily derived from the type of clay used, depending on its natural characteristics. Additionally, the surface texture and overall appearance of bricks are shaped by the manufacturing process, including the use of dies, molds, or attachments that imprint or modify the surface of the bricks during production.

Freeze-thaw is the process where water absorbed within a brick expands upon freezing and contracts when it thaws, leading to the degradation of the brick. The brick's ability to resist this type of damage is called durability.

Brick durability is graded, with SW-grade bricks being the most durable due to their high strength and low water absorption, followed by MW-grade and then NW-grade bricks.

The compressive strength of building and face bricks generally ranges from 1500 to 3000 pounds per square inch.

The strength of brick masonry mainly depends on the strength of the mortar, reinforcement, and the bricks themselves.

The appearance of bricks is influenced by changes in their size, alterations in their shape, and the degree of visible damage on the brick's face or corners, with the amount of chippage also being a consideration for the appearance of the bricks.

The color of bricks mainly comes from the clay type, while their surface texture and appearance are shaped by the dies, molds, or attachments used during the manufacturing process.