Chip sealing is the process of spraying emulsified asphalt on the road and dropping a layer of aggregate on the liquid asphalt then rolling over it with a rubber tire roller to set the aggregate into the asphalt. This provides a new wearing course and seals small cracks to prevent water from penetrating into the road base. $14,300 per lane mile was the average price for this treatment for projects let in 2014.
Microsurfacing is a mix of polymer-modified asphalt emulsion, mineral aggregate, mineral filler, water, and other additives, which are proportioned, mixed, and spread on a paved roadway at a specified thickness. As the water evaporates, the surface cures providing a new skid-resistant surface and sealing small cracks to prevent water from penetrating into the road base. Microsurfacing can also be used to correct wheel path rutting. $33,700 per lane mile was the average price for this treatment for projects let in 2014.
Ultra-Thin HMA is applied with an asphalt paver and promptly compacted with a steel wheel roller. This treatment is ready for traffic almost immediately after compaction. Thin HMA overlays provide a new asphalt surface and prolong the pavement structure life. This thin (0.5 to 1.0 inch) surfacing provides the benefits of an asphalt surface at a low cost that helps maintenance dollars go farther. $33,500 per lane mile was the average price for this treatment for projects let in 2014.
Crack Sealing is the filling of moderately sized cracks with hot liquid rubberized asphalt material. This seals the cracks in the road surface and reduces the amount of moisture entering the subsurface layers and thus extends the pavement life. Crack sealing is a very cost effective method of pavement preservation. $1,900 per lane mile was the average price for this treatment for projects let in 2014.
Involves digging out the asphalt and the base below it. Then we rebuild that area of the road.
By now you may be seeing a theme here. All of these procedures are to either prevent water from entering the base or to repair the base once it has been damaged by the infiltration of water.
SCDOT takes a proactive approach to preserve our highway system by employing a set of planned pavement maintenance strategies.
We have separated our paving program into three primary elements:
Preservation
The pavement preservation program is a proactive approach to maintaining South Carolina's roads using low cost preventive maintenance treatments. Moving from a worst first strategy to one of preservation will ensure that we are getting the most from the limited resurfacing dollars available.
Chip SealingAdditional information about pavement preservation can be found at the National Center for Pavement Preservation.
Rehabilitation
Rehabilitation projects extend the life of existing pavement structures either by restoring existing structural capacity through the removal and replacement of deteriorated pavement surface or by increasing pavement thickness to strengthen existing pavement sections to accommodate existing or projected traffic loading conditions.
Rehabilitation treatments are much more expensive than preventative maintenance, it is a cost effective technique to address failing pavements before they require reconstruction.
Reconstruction
Reconstruction usually requires the complete removal and replacement of the existing pavement structure. It is appropriate when a pavement has structurally failed and can no longer support the traffic demand. Reconstruction increases the structural capacity of the pavement to a level that is required for long term performance.
Section 58-35-50
Per the Underground Utility Damage Prevention Act - Section 58-35-50, SCDOT is required to notify utility companies of preventive maintenance activities. The primary preventive maintenance activity that poses a threat to underground utilities is our shoulder and ditch program.
Vegetation Management Guidelines
The purpose of the SCDOT Vegetation Management Guidelines is to provide information necessary to maintain the Department's roadsides in a manner that will:
Herbicide Operations Manual
The purpose of the SCDOT Herbicide Operations Manual is to provide information and guidance in promoting the safe and proper use of herbicides, thereby protecting the environment and the public health while performing indispensable highway maintenance and safety as part of the South Carolina Department of Transportation's Integrated Roadside Vegetation Management Program.
Guardrail Inspection and Repair Guidelines
The SCDOT Maintenance Division is presently responsible for the inspection, maintenance, and repair of over eight million linear feet of guardrail, over thirty-six thousand end anchor systems, 470 miles of median cable barrier and 150 crash attenuators presently located within the Department's rights-of-way. These guardrail inspection and repair guidelines provide direction for the inspection, maintenance, and prioritization of the repair of these systems.