North Carolina General Contractors Practice Exam

What does the 'compressive strength' of mortar refer to?

1. The ability to resist bending

2. The maximum load a material can withstand without failure

3. The speed of setting

4. The aesthetic appearance of the joint

The correct answer is: The maximum load a material can withstand without failure

Compressive strength of mortar is defined as the maximum load that the material can withstand without failure when subjected to axial loading. This property is crucial in construction since mortar is often used to bond bricks or stones in masonry, and it must support the weight and loads imposed by the materials above it. Understanding the compressive strength helps ensure the structural integrity and durability of the construction. While the ability to resist bending is relevant to materials under flexural stress, it does not specifically pertain to the compressive strength of mortar. The speed of setting refers to how quickly mortar hardens, which is a different characteristic related to its workability and application time. Similarly, the aesthetic appearance of the joint relates to visual considerations and finishes, not to the load-bearing capacity of the mortar itself. Therefore, the focus on the ability to withstand maximum loads without failure directly identifies why the definition regarding compressive strength is correct.