Search results
Results from the WOW.Com Content Network
The first macadam road built in the United States was constructed between Hagerstown and Boonsboro, Maryland, and was named at the time Boonsborough Turnpike Road. This was the last section of unimproved road between Baltimore on the Chesapeake Bay to Wheeling on the Ohio River .
John Loudon McAdam, 1830, National Gallery, London. John Loudon McAdam (23 September 1756 [1] – 26 November 1836) was a Scottish civil engineer and road-builder. He invented a new process, "macadamisation", for building roads with a smooth hard surface, using controlled materials of mixed particle size and predetermined structure, that would be more durable and less muddy than soil-based tracks.
Asphalt batch mix plant A machine laying asphalt concrete, fed from a dump truck. Asphalt concrete (commonly called asphalt, [1] blacktop, or pavement in North America, and tarmac or bitumen macadam in the United Kingdom and the Republic of Ireland) is a composite material commonly used to surface roads, parking lots, airports, and the core of embankment dams. [2]
Tarmacadam is a concrete road surfacing material made by combining tar and macadam (crushed stone and sand), patented by Welsh inventor Edgar Purnell Hooley in 1902. It is a more durable and dust-free enhancement of simple compacted stone macadam surfaces invented by Scottish engineer John Loudon McAdam in the early 19th century.
Although McAdam had been adamantly opposed to the filling of the voids between his small cut stones with smaller material, in practice road builders began to introduce filler materials such as smaller stones, sand, and clay, and it was observed that these roads were stronger as a result. Macadam roads were being built widely in the United ...
About half of all Americans take one prescription medication each and every day. Short doctor visits, savvy pill marketing, and habit convince us that every doctor's appointment should end in a ...
During the early and mid-20th century, when town gas was produced, coal tar was a readily available byproduct and extensively used as the binder for road aggregates. The addition of coal tar to macadam roads led to the word "tarmac", which is now used in common parlance to refer to road-making materials. However, since the 1970s, when natural ...
U.S. Democratic lawmakers Friday sent letters to two federal agencies asking them to explain why they froze federal funds on clean energy and investments that lower energy costs for American ...