AG Mechanics CDE Practice Exam

A groove cut into concrete to allow for expansion due to temperature changes is called an:

1. control joint

2. expansion joint

3. isolation joint

4. construction joint

The correct answer is: control joint

A control joint is a groove cut into concrete to allow for expansion due to temperature changes. This is different from an expansion joint (B), which is typically a separate piece used to create a gap between concrete slabs. An isolation joint (C) is used to separate different parts of a concrete structure to prevent cracking due to movement, not just expansion. Finally, a construction joint (D) is where two separate concrete placements meet, and is not specifically created to account for temperature changes.