Concrete Roads
and Their Construction

År: 1920

Serie: Concrete Series

Forlag: Concrete Publications Limited

Sted: London

Sider: 197

UDK: 625.8 Con-gl.

Being a Description of the concrete Roads in the United Kingdom, together with a Summary of the Experience in this Form of Construction gained in Australia, Canada, New Zealand and the United States of America.

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CHAPTER V THE GROWTH OF CONCRETE ROADS IN THE UNITED STATES AMERICAN ROADS AND THEIR DEVELOPMENT UP TO 1920 At the close of the year 1909, there were six miles of concrete road in all of the United States. At the close of 1919 there were 11,400 miles of concrete road. These mileage figures are based on the actual yardage built, and since different roads are constructed of different widths the usual road width of 18 ft. was used for the pur- pose in hand. So the growth from practically zero to a mileage that would span the continent from the Atlantic to the Pacific more than three times shows how the popularity of these roads has in- creased. The study of the evolution of concrete roads cannot well be carried on without at the same time taking note of the develop- ment and use of the automobile. In 1909 there were 127,731 cars in the United States, whilst at the end of 1919 a total of almost 8,000,000 was reached, with an annual production of nearly 2,000,000 cars. It will readily be seen that the develop- ment of concrete roads and that of the motor driven vehicle have been side by side. Carrying the motor-car figures a little further, it is found that in the United States there is one car for every fourteen persons, and automobile manufacturers expect production for 1920 to be greatly increased. Motor-cars demand a smooth, rigid road. It was not so with roads when the horse was the motive power. Horse-drawn travel compacts dirt and gravel roads, while motor traffic disrupts these same roads. The speed of trucks and automobiles is at least five times greater than that of the wagon and surrey,* likewise the cost of driving intricate and expensive motor vehicles is correspondingly more expensive on poor roads. It is particularly interesting, as we bear in mind that concrete roads and automobiles have developed side by side, to notice another fact. Detroit, Michigan, is the centre of the automobile industry, * A four-wheeled pleasure carriage (commonly two-seated), somewhat like a phaeton, but having a straight bottom. 115