Concrete Roads
and Their Construction

GROWTH OF CONCRETE ROADS IN UNITED STATES 121 operations. With the motor-car they could attend to more business than ever before, and with the truck they were able to take care of the increased business that came. Rural communities began to want concrete roads. Now the farmers became consistent supporters of concrete highways for their trucks and motor-cai’s. Then came the entry of the United States into the World War. The mobilization of 4,000,000 men for arms and the mobilization of the remainder of the population for industrial work made labour unavailable for continued road construction. Moreover, had labour been available, material and transportation could not have been furnished, since it, too, was diverted to war work. The country at large had, as we have said, become educated to good roads, and now came severe tests that were to prove the soundness of its logic in asking for permanent roads. Particularly around army camps and the roads traversed by military trains pavements were put to the crucial test. Heavy pieces of artillery and endless trains of heavy trucks carrying war supplies rapidly wore down all pavements that were not of the highest class. Gravel and macadam roads failed rapidly. Many other types that wei’e considei’ed. fair under peace-time conditions gave way before the strain. It is interesting to observe that where the army engineers reconstructed these military roads they were usually built of concrete and successfully withstood the severe punishment that our military establishments imposed upon them. Reverting to the actual mileage constructed during the war period, we find that 1,533 miles of concrete road were built in 1917 and 1,300 miles in 1918. The situation, then, at the signing of the Armistice in November, 1918, was this : Before the war the popularity of the automobile had created a widespread sentiment for good roads, and the heavy punishment that roads received under war-time conditions proved that concrete roads were better able to stand the stress than other types. After the war was over there was a strong, widespread sentiment throughout the United States to build roads. The various States and other road-building units gave lai’ge contracts, and in 1919 4,130 miles were built or contracts awarded. It was the premier year for road construction. With hardly an exception every State increased its mileage. The State of Illinois, which contains the city of Chicago, voted $60,000,000 worth of bonds to build State highways. The same day that Illinois pledged itself to spend $60,000,000