Concrete is a composite material made up of various types of stone aggregate that are held together with a mixture of water and lime-based binder—usually Portland cement. The typical mixture used in driveway slabs, sidewalks, and other paving surfaces usually uses a mixture of aggregate ranging from gravel to sand-sized particles.
Installing a concrete driveway starts with excavating any dirt or unsuitable material. Wood forms are then installed around the perimeter of the intended driveway. A base of class-5 gravel, 4 inches thick, is added and graded and compacted. Reinforcement material is added just above the packed gravel base, consisting of a steel wire grid or metal rebar laid in a criss-cross pattern across the area.
The driveway is now ready for the concrete pour. This generally involves a crew of several people working quickly to fill the forms with wet concrete. The finishing crew should also ensure an adequate number of contraction joints—grooves formed across the wet surface at prescribed intervals to allow the slab to shift and break at controlled places. Usually every
8' ft. to 10' ft. Without contraction joints, a slab can fragment randomly under the effect of natural settling and shifting.
After the concrete is poured and smoothed, the finishing crew uses a variety of tools to work the surface of the concrete, drawing the cement and finer particles to the surface to create an attractive, smooth surface.
One of the most important parts of a concrete driveway installation begins after all of the above work is done—the curing. It is very important that this curing process occurs under the best of circumstances. Ideal curing starts with a surface that is kept damp but not wet. In cool weather, curing will take longer. In hot weather, the surface should be dampened regularly with water to slow down the curing time.
We recommend waiting at least 5 days before driving on the new driveway.
Concrete driveways generally remain functional for 25 to 30 years, depending on how well built they were and how well they have been maintained.