Street Maintenance Strategies
Street maintenance is routine work performed to keep the pavement in a condition as close as possible to its newly constructed condition. This results in a cost-effective use of limited available funds and provides maximum benefit to the traveling public by enhancing the safety of the roadway and improving ride comfort of the road surface. Street maintenance strategies can be divided into 2 categories: maintenance and resurfacing.
Maintenance strategies (or activities) are done in preparation for upcoming scheduled resurfacing and include the types of repairs listed below:
Crack sealing is where cracks are filled with hot applied rubberized material to prevent water infiltration into the road base.
Base repair is the removal of any distressed areas where the pavement is fractured and broken and is allowing water to weaken the subgrade under the roadway. Various methods are used to remove the distressed asphalt, such as backhoe and cold mill planers. Once removed new asphalt is placed.
Tree Root Removal
Tree root removal is the removal of raised areas in the pavement caused by tree roots. Either the areas are completely removed and replaced or ground down and patched.
Skin Patching is where low areas that are imperfections in the asphalt are patched with asphalt concrete. Typically these depressions are small and have settled over time. This gives the street a patchwork appearance.
Resurfacing strategies include the techniques that are listed below. The appropriate resurfacing treatment for a roadway depends on the existing pavement condition. It is more cost effective to resurface a street before pavement deterioration becomes severe, requiring reconstruction.
The highest form of street maintenance, overlay involves the placement of a new layer of asphalt, approximately 1.5 to 3.5 inches thick, on the street. The construction cost to overlay a street is approximately $18 per square yard depending upon the thickness required. Properly maintained, an overlay can extend the life of the street by 20 to 25 years although heavily used streets may require more frequent overlays.
Cape seal is a chip seal followed by a slurry seal. This process gives the strength of a chip seal with the added benefit of a smoother riding surface; therefore it is used instead of a chip seal. Cape sealing can extend the life of a street by 9 to 12 years.
Chip seal is an application of liquid asphalt followed by the placement of small rock chips on the existing pavement. This treatment adds strength to the existing pavement and can extend the life of the street by 8 to 10 years.
Slurry seal is a blend of oil and small aggregate applied to the streets. Slurry seal is a preventative maintenance procedure. Slurry sealing can extend the life of a street by 5 to 7 years.