What role do expansion joints play in concrete flatwork?

Expansion joints are designed to accommodate movement in concrete structures due to temperature fluctuations. When concrete is subjected to temperature changes, it expands when heated and contracts when cooled. Without expansion joints, this movement can lead to cracking or structural damage as the concrete tries to accommodate these changes naturally. The presence of expansion joints allows for controlled movement, thus protecting the integrity of the slab and maintaining its longevity.

While connecting different slabs may seem relevant, this function primarily pertains to the design and layout of the concrete work rather than the specific role of expansion joints. Similarly, while strength is essential in concrete slabs, expansion joints do not inherently increase the strength; instead, they manage movement. Lastly, while heavy loads can affect concrete, this is not the primary purpose of expansion joints; they were specifically created to address temperature-induced changes rather than load-induced wear.