What is the Achilles' heel of a masonry wall?

What is the Achilles' heel of a masonry wall?

• A. Steel
• B. Mortar
• C. Brick
• D. Concrete

Answer: (B)

Mortar is the Achilles' heel of a masonry wall because it is the binding that holds the bricks or blocks together and transfers loads between them, yet its own strength is comparatively weak. Masonry units like bricks or blocks are strong in compression, but the joints—where they are connected by mortar—are the system’s point of vulnerability. Mortar has lower tensile and shear strength and is more susceptible to deterioration from moisture, salts, and weathering. When the mortar deteriorates, joints crack, spall, or lose bond, and the wall’s ability to carry loads and resist lateral forces diminishes. Even though the bricks or blocks provide most of the vertical strength, the overall stability hinges on the integrity of the mortar joints, making mortar the weak link in the assembly.

Mortar is the Achilles' heel of a masonry wall because it is the binding that holds the bricks or blocks together and transfers loads between them, yet its own strength is comparatively weak. Masonry units like bricks or blocks are strong in compression, but the joints—where they are connected by mortar—are the system’s point of vulnerability. Mortar has lower tensile and shear strength and is more susceptible to deterioration from moisture, salts, and weathering. When the mortar deteriorates, joints crack, spall, or lose bond, and the wall’s ability to carry loads and resist lateral forces diminishes. Even though the bricks or blocks provide most of the vertical strength, the overall stability hinges on the integrity of the mortar joints, making mortar the weak link in the assembly.