In 1792, the first turnpike was chartered and became known as the Philadelphia and Lancaster Turnpike in Pennsylvania. It was the first road in America covered with a layer of crushed stone. In 1806, the Federal Government passed legislation to fund the National Road, known as the Cumberland Road.

Settlers purchasing land from the government generated revenue for the federal government to build roads. This revenue was an important source for road building and maintenance, especially in sparsely populated areas.

Inclusion of the 2,102 miles of toll roads in the Interstate System will not affect their status as toll roads. The Federal-Aid Highway Act of 1956 permits this, although no Federal-aid funds may be used for their improvement.

Once the turnpike road was completed, the companies charged tolls to those who traveled the road in order to make a profit and repay its investors. Many of these early toll roads kept the name ‘Turnpikes’ – it conveyed to people that a charge would be made for using the road.

Originally Answered: Why do we have so many toll roads on the east coast of US compared to the rest of the country? The East Coast has a number of toll roads from which the maintenance costs of the state roads are derived.

The National Road

Woodward Avenue

Professor Edward J. de Smedt

The word asphalt comes from the Greek “asphaltos,” meaning “secure.” The Romans used it to seal their baths, reservoirs and aqueducts. Europeans exploring the New World discovered natural deposits of asphalt.

The main difference between Tar and Asphalt is that the Tar is a substance and Asphalt is a sticky, black and highly viscous liquid or semi-solid form of petroleum; bitumen variety. Tar can be produced from coal, wood, petroleum, or peat.

Bitumens have a better durability and resistance to weathering than tars. Tars are more susceptible to temperature changes than bitumens. Hot weather will soften a tar surface more than a surface made with bitumen of the same viscosity, and it will become more brittle at low temperatures than bitumen.

Bitumen is actually the liquid binder that holds asphalt together. The term bitumen is often mistakenly used to describe asphalt. A bitumen-sealed road has a layer of bitumen sprayed and then covered with an aggregate. Asphalt results in a smoother and more durable asphalt road surface than a bitumen-sealed road.

Different Types of Bitumen, their Properties and Uses

• Penetration Grade Bitumen.
• Oxidized Bitumen.
• Cutback Bitumen.
• Bitumen Emulsion.
• Polymer – Modified Bitumen.

What is Bitumen? Bitumen is obtained by the partial distillation of crude petroleum. It is also called as mineral tar and is present in asphalt also. It contains 87% carbon, 11% hydrogen and 2% oxygen.

Bitumen gain Adhesive Nature As explained in the production of bitumen, it is free from hydrocarbon and hence not toxic. The bitumen has a highly adhesive nature, which keeps the materials in the road mix bind together under strong bonds. These become stronger when the mix is set i.e. ready for vehicle movement.

Colored Bitumen Traditional asphalt bitumen is black because of the dense organic material that makes up the material. Colored bitumen is also available and has pigments added to the solution.

Viscosity Grading of Bitumen

Bitumen Penetration Grade 60/70 is a standard penetration grade Bitumen usually used as a Paving Grade Bitumen suitable for road construction and for the production of asphalt pavements with superior properties. This grade of Bitumen is mainly used in the spraying and chip applications.

2.1. 2 Bitumen 60/70: This grade is harder than 80/100 and can withstand higher traffic loads. The characteristics of this grade confirm to that of S 65 grade of IS- 73-1992. It is presently used mainly in construction of National Highways & State Highways.

Penetration Grade 80

New Grading by Indian Standards This standard recommended five grades of bitumen viz. S-35, S-45, S-65, S-90 and S-200. The key requirements for bitumen were the specific gravity, penetration, water content, flash point, softening point, ductility, loss on heating test and solubility in trichloroethylene.