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Show WASTE IS BUGBEAR IN ROAD BUILDING Few motorists as they roll smoothly smooth-ly over tie magnificent pavements now found in many parts of the eoun-j eoun-j try realize the detailed and painstak- ing research which preceded the luy- ing of the pavement. To many, a road Is a road, and no matter what the type of surface or the local conditions, condi-tions, road building to them is large-, ly a matter of smoothing the ground and providing some kind of a hard surface. Hut had such a policy been followed, fol-lowed, millions of dollars would have been wasted, and the country would today be mired iu a bog of replacement, replace-ment, repair and reconstruction. He-cause He-cause of the farsightedness of engineers en-gineers in charge of road building this possible waste has been prevented, and the pavements being laid today are the best possible. Road construction, as practiced today, to-day, is a highly specialized business. Good, permanent construction insures years of earning power and the saving sav-ing of millions of dollars in transportation transpor-tation costs. Poor construction means waste that mounts into almost countless count-less figures. Foremost among the possible sources of waste is the construction of roads of lower type than justified by traffic. Tests conducted in many parts of the country have proved that a road should be built according to its maximum maxi-mum requirements rather than to its minimum. A dirt "-"id carrying a traffic of 110 tons per day, in general, gen-eral, will pay for grcot in ten years by the saving in operating costs. Traffic on a dirt road exceeding 610 tons per day or traffic on a gravel road exceeding 1,450 twAs per clay will, in general, pay for a concrete, brick or asphalt road in fifteen years by the saving. These figures, established by the Iowa highway commission, are today to-day being taken as standard for determining de-termining the type of surface justified. Scientific, research has established some remarkable facta about sub-grades. sub-grades. Formerly it was held that all soils conld be drained, no matter how wet and unstable In their natural condition. con-dition. On the Bates road In Springfield, Spring-field, 111., two years were spent in Investigating In-vestigating drainage. Tests firmly established es-tablished the fact that in clay soils, little can be done to reduce the moisture mois-ture content by drainage. The wastes in highway funds saved through this research returned taxpayers millions of dollars. Again referring to . the Bates test, which is perhaps the most comprehensive compre-hensive yet conducted, tests have made it possible to build a road which is permanent and able to stand up under un-der any given volume of traffic if properly maintained. Through research re-search the public is now protected against building road pavements too light for the volume of traffic which will use the road and which break flown under traffic. Similarly, after having determined the volume of traffic, road builders need not build a pavement too heavy for the traffic the road will carry. This saves overinvestment in road pavements. |