Chipseal (also chip seal ) is a curb surface treatment that combines one or more bitumen layers with one or more fine aggregate layers. In the United States, chipseals typically used on rural roads carry a lower volume of traffic, and this process is often referred to as "asphalt surface treatment". In Australia and New Zealand chipsealing is used on a larger percentage of roads, both rural and urban. This type of surface has various other names including "tar and chip", "seal being sprayed" or "surface dressing".
Video Chipseal
Histori
The chipseal method was developed in New Zealand in 1935 by Frederick Melrose Horowhenua Hanson while working for the Department of Public Works (later the Ministry of Works and Development).
Maps Chipseal
Usage
Chipsealing is cheaper than re-coating asphalt concrete or cement concrete pavement in Portland, but not durable. In some US states, chipsealing is used in conjunction with the construction of new roads to make sleep paths more durable and durable.
Installation
Chipseals are built by evenly distributing a thin base of hot bitumen or asphalt onto an existing pavement and then embedding a fine graded aggregate into it. The aggregate is distributed evenly over the seal spray, then rolled onto the smooth sidewalk surface. A surface-seal pavement can be optionally sealed with a top layer, called a mist seal or enrichment.
The introduction of polymer-modified asphalt and emulsion binder has improved the chipseal ability to prevent crack reflections and improve rock retention by improving asphalt binder properties. Newer techniques use asphalt emulsions (liquid asphalt mixtures, surfactants, and water) instead of asphalt. This has been shown to help reduce aggregate loss and reduce installation costs, but can improve stripping (separation of binders from aggregates). This reduces the emissions of volatile organic compounds (VOCs) due to lower solvent content. The new method also uses crosslinked polish polymers that also provide quality water resistance. Chips precoated with about one percent bitumen have been successfully used to minimize aggregate loss and give the surface a black look.
It can keep a good sidewalk in good condition by sealing the water, but it does not provide structural strength and will only fix small cracks. While small stones used as surfaces produce relatively flat surfaces without edge fillings, it also produces a very rough surface that leads to a louder sound from the wheels of the car.
Although chipseal is an inexpensive, effective way to fix the road, it has several disadvantages. Stones that are crushed loosely are often left on the surface, due to the application of bitumen or overapplication of unfavorable stones. If not removed, this can cause safety and environmental problems such as cracked glass, flaky paint, crashes lost control (especially for motorcyclists, cyclists and small trucks), and deposition of foreign material into drainage courses. Therefore, it is very important to sweep the path after the set of emulsions. As mentioned earlier, this problem can be minimized by using chips beginning with bitumen. Overapplication of emulsions can cause bleeding, a condition in which excess asphalt rises to the surface, creating a very smooth surface that is very slippery when wet and bulging in hotter summers. When the car drove it, the tire kicked this floating substance to the side of the car. It can only be cleaned with solvent or diesel remover.
Noise and vibration effects
A rough chipseal surface produces more road noise at any operating speed than regular asphalt or concrete surfaces. The intensity of this sound increases with the speed of a higher vehicle. There is a considerable range in the resulting acoustic intensity depending on the design of the particular tread tread and its interaction with the type of road surface.
Rough surfaces cause a noticeable increase in vibration and rolling resistance for cyclists, and increased tire wear in all types of tires.
The speed of the vehicle can affect the time set up with chipseal. Shortly after construction (depending on weather conditions) the speed set for chipseal is 10-15 miles per hour (16-24 km/h) for the first 24-48 hours after construction.
See also
- Macadam
- Asphalt
- Bitumen surface
References
External links
- Grand Junction City, CO page on Chipseal
- TRL Design Guide for Surface Dressings (Road Note 39)
Source of the article : Wikipedia
0 Comments