Curb
Although curbs have been used throughout modern history, and indeed were present in ancient Pompeii,[1] their widespread construction and use only began in the 18th century, as a part of the various movements towards city beautification that were attempted in the period.
The corporation was also made responsible for the regular upkeep of the roads, including their cleaning and repair, for which they charged a tax from 1766.
[5] In 1945, Jack Fisher of Kalamazoo, Michigan, celebrated the installation of one of the nation's first curb cuts to facilitate mobility in the center of the city.
[5] In the United States, activism and passage of federal legislation on accessibility requirements such as the Americans with Disabilities Act of 1990 (ADA) have facilitated travel for wheelchair users and other people.
[6] By delineating the edge of the pavement, they separate the road from the roadside and discourage drivers from parking or driving on sidewalks and lawns.
[6] On higher speed roads, the main function of curbs is to provide drainage, and they are mostly used in areas of a bridge approach or other locations with erosion risk.
[9] For example, cultural context and behavioral norms of a society may affect safety in that people are more likely to cross on a red light while standing alone than waiting with others at the curb.
Trends include using a 24-inch (610 mm) gutter that balances the increased initial price with lower maintenance costs.
Wider curb cuts are also used to allow motor vehicles to cross sidewalks at low speed, typically for driveways.
In Great Britain, "high containment kerbs" are used at locations with pedestrians, fuel station pumps, and other areas that need greater protection from vehicle traffic.
These are 14 inches (36 cm) high - much higher than standard curb, with a sloped lower portion and a concave face.
[12] Curbs are constructed of many materials, including asphalt, stone, or masonry blocks, but most often are made of Portland cement concrete.
[15] One of the recommendations has been using a 4/12 batter in to accommodate automobile design because steeper batters tend to interfere with body trim, hubcaps, and lower door edges while curb faces in excess of 6 in (152 mm) in height may prevent the full opening of car doors.
If the main roadway and gutter settle differently over time, the vertical edge that develops at the joint can cause a hazard for bicyclists.
Although they are not considered part of the racing track,[19] drivers sometimes "ride the curbs" in order to maintain momentum and gain a time advantage in cornering.
More explicitly, curbstones can be painted (by official sanction or otherwise) to stress an identity or ideology; for instance, in Northern Ireland, curbstones are frequently painted in communities to identify a religious/political affiliation – typically either red, white, and blue for Unionist/Loyalist areas, and green, white, and orange for Nationalist areas.
