Concrete and Asphalt: Effective Maintenance
August 21, 2012
I’m Dan Hounsell, editor of Maintenance Solutions
magazine. Today's topic is, effective concrete and asphalt maintenance.
Exterior concrete and asphalt surfaces create a visitor's first impression of a facility. If drives, parking lots, and sidewalks deteriorate because they are not maintained properly, they can create problems that include poor appearance, tripping hazards, and costly repairs.
The causes of concrete and asphalt problems generally fall into three categories: design, use, and maintenance.
Design problems result from errors in material makeup, the placement of reinforcing materials, and poor support structure. One common design problem is excess water in the concrete mix. Managers need to properly specify concrete and asphalt mixes for each application and inspect them during application to ensure workers take test specimens and place the materials properly.
Another common problem is surface spalling, which results from imbedded metal around windows and other locations that strengthens concrete. Structural settling causes cracks that allow water intrusion, freezing and more cracking.
Even properly applied asphalt can develop problems that result from the effects of ultraviolet rays, water, petroleum products, and traffic. New asphalt combines asphalt-cement binder, sand and stone, and it is black. As the surface dries, asphalt turns gray from the absence of binder, and the elements begin to deteriorate it.
Managers also must be aware of unintended traffic, which can lead to premature degradation. For example, parking lots feature lanes for cars and those for trucks, which have much thicker bases.
If the design does not provide truck lanes or if trucks wander off designated lanes, they will crush the car-parking surfaces. The resulting depressions will collect standing water, and the water will turn to ice. Cracking and spalling can occur, causing damage that requires major repairs.