Why are dowel bars used in joint construction for concrete pavements?

Dowel bars are crucial components in the construction of concrete pavements primarily because they serve to transfer loads across the joints and help control cracking. When concrete slabs expand and contract due to temperature changes, the dowel bars ensure that the weight of traffic is distributed evenly across the joint. This transfer of load minimizes differential movement between slabs, which is a key factor in controlling the occurrence of cracking.

By effectively aligning the slabs and allowing for controlled expansion and contraction without leading to misalignment or damage, dowel bars enhance the overall durability and lifespan of the pavement. The proper use of dowel bars directly contributes to reducing maintenance costs and prolonging the integrity of the pavement structure.

The other options do not directly address the primary purpose of dowel bars in concrete pavement. Enhancing aesthetics, stabilizing soil, or speeding up curing are not the main functions of dowels in this context. Dowel bars are specifically engineered for load transfer and crack control, making them an essential element in joint construction for concrete pavements.