What is the primary purpose of a dowel?

What is the primary purpose of a dowel?

• A. To fill voids in the concrete.
• B. To help control movement, prevent cracking, and maintain the alignment of concrete sections.
• C. To reduce concrete strength.
• D. To carry moisture across joints.

Answer: (B)

Dowels are placed at concrete joints to transfer horizontal load from one slab to the next while allowing the slabs to move independently in response to temperature changes and shrinkage. By carrying shear across the joint, they keep the slabs aligned and reduce cracking and spalling that can occur at the joint under traffic. Their smooth, load-sharing design lets the joint move vertically or rotate slightly without binding, so the joint remains tight and the overall pavement behaves like a continuous structure. They don’t fill voids, don’t reduce strength, and aren’t meant to carry moisture across joints.

Dowels are placed at concrete joints to transfer horizontal load from one slab to the next while allowing the slabs to move independently in response to temperature changes and shrinkage. By carrying shear across the joint, they keep the slabs aligned and reduce cracking and spalling that can occur at the joint under traffic. Their smooth, load-sharing design lets the joint move vertically or rotate slightly without binding, so the joint remains tight and the overall pavement behaves like a continuous structure. They don’t fill voids, don’t reduce strength, and aren’t meant to carry moisture across joints.