what is chip sealing?
Chip Sealing (also know as Spray Sealing, Surface Dressing) is the application of a bituminous binder immediately followed by the application of an aggregate. The aggregate is then rolled to embed it into the binder. Multiple layers may be placed and
various binder and aggregate types can be used to address specific distress modes or traffic situations.
Chip sealing is one of the oldest and most widely used form of road pavement structures. Originally used for low-medium traffic roads, chip sealing has evolved (with newer bitumen emulsions) and is now used also in high traffic roads as pavement maintenance. New Zealand, has over 92,000 kilometers of road network, with 60,000 kilometers chip sealed. Similarly, Australia has over 800,000 kilometers of road network. 500,000 kilometers are gravel roads, and 270,000 kilometers are chip sealed. In the USA, and in Europe, chip seals are the most common type of surface dressing used as it is relatively cheaper, and durable.
Chip seals do not increase the load bearing capacity of the road. Thus, chip seals are best applied only on roads that have good structural integrity (e.g. stabilized roads)
various binder and aggregate types can be used to address specific distress modes or traffic situations.
Chip sealing is one of the oldest and most widely used form of road pavement structures. Originally used for low-medium traffic roads, chip sealing has evolved (with newer bitumen emulsions) and is now used also in high traffic roads as pavement maintenance. New Zealand, has over 92,000 kilometers of road network, with 60,000 kilometers chip sealed. Similarly, Australia has over 800,000 kilometers of road network. 500,000 kilometers are gravel roads, and 270,000 kilometers are chip sealed. In the USA, and in Europe, chip seals are the most common type of surface dressing used as it is relatively cheaper, and durable.
Chip seals do not increase the load bearing capacity of the road. Thus, chip seals are best applied only on roads that have good structural integrity (e.g. stabilized roads)
the process
Chip sealed roads can last 12-17 years (click here to jump to reference). These can be achieved using the modern types of bitumen emulsions applied using specialist equipment. Bitumen emulsion is sprayed and immediately followed by aggregate chips.
the benefits
Benefits of using chip seals include
- Waterproofing (protects the road, and the subgrade from water ingress)
- Skid Resistance
- Wearing course
- Black top appearance/appeal
- Much cheaper than standard hot mix asphalt roads