Chip Seals (or seal finish, BST, Bituminous Surface area Treatment) is the application of a unique safety wearing surface area to an existing pavement.
Chip Sealing
A dump truck filled with chips (gravel) locks on to the chip spreader and is pulled backwards.
A thin layer of liquid asphalt is sprayed down in front of the chip spreader.
Why chip seal?
- To keep water from penetrating the road structure on paved surface areas.
- To fill and seal cracks and raveled surface areas of old pavement.
- To supply an anti-glare surface throughout wet weather and an enhanced reflective surface area for night driving.
- To seal the pavement surface-minimizing the results of aging.
- To provide a highly skid-resistant surface, specifically on wet pavements.
- The cost of chip seals is 15 % -20 % of the expense of pavement overlays.
The Chip Seal Process
Asphalt is blended with about 30 % water. This emulsified mix is then applied to the road making use of a special spray truck. As quickly as the liquid asphalt meets the roadway surface, the water begins to vaporize.
Instantly after spraying this asphalt, a layer of crushed gravel is used by a spreader. The gravel (or chips) has a maximum size of 3/8 inch.
Next, the gravel is compacted and embedded into the asphalt by rubber-tired rollers. Nevertheless, even with the high pressure rolling, some gravel will not end up being embedded in the asphalt.
The brand-new chip-seal surface area can require approximately 2 days to treat appropriately. Hot, dry weather condition assists speed up this procedure in which all of the continuing to be water in the emulsion vaporizes and the asphalt solidifies. Traffic can pass over this surface at minimized speeds during the treating process.
After treating, the loose gravel is swept the surface area. This might take numerous sweepings.