Concrete pavements have a long life and require little maintenance. Concrete is generally laid as a single thick layer directly over a base course. Concrete is usually laid in long sections or slabs of varying length. Metal bars or dowels inserted into the edges of the slabs help connect the joints where one slab ends and another begins. When the ground underneath expands and contracts from seasonal or weather changes, the concrete becomes prone to cracking.
Cracks can occur at or near the joints where concrete slabs meet or on the slabs themselves.
Deep cracks can allow the broken concrete slabs to move upward or downward, creating an uneven road surface. Metal bars or dowels inserted between the slabs help hold the slabs together. Reinforced concrete contains steel bars or mesh imbedded within the concrete layer. The steel helps hold concrete together over time, even if cracks occur. Unreinforced concrete may be used when cost is a factor, or where weather conditions are more mild.