Show o SCIENTIFIC ROAD BUILDING Test Being Made In Illinois to D Determine Determine De De- termine What Pavement Can Be Used on Highways Prepared by the United States Statu Department t of Agriculture e Some time within the next nest few fer months a new roal road 2 21 miles long Is to tobe tobe be broken up In what Is probably the most extensive study of road service ever undertaken In the United States Stains The road Is located In Illinois about 12 miles mUes southwest of ot Springfield and parallels the railroad In tl tile the e test road there are no curves The grades vary ary from zero to tenths four-tenths of ot 1 per cent with an average grade of ot tenth one-tenth of ot 1 per cent the and minimum grades extending over Very cry short distances The soil Is uniformly a brown silt loam except for two small stretches where It more nearly approaches s gumbo There are seven general types of caving DaTIng paving DaT- DaT ing In the road the Idea being to lo have represented the chief materials used use In lu road making milking so that engineers may study the effect of known und and measured traffic of ot varying degree upon each kind of road The seven types are Portland cement concrete Three and four tour Inch lug brick constructed constructed constructed con con- monolithic and with a Portland Portland Port Port- land cement concrete base Three and four Inch lug brick constructed constructed con and with ft ri Portland cement concrete base Three and four tour Inch bituminous tilled filled lug and brick on Portland c cement cement ce ce- ment concrete base Three and four tour Inch bituminous Jilted tilled lug and brick on macs macadam dam base concrete with and out binder course on macadam base The road known as the Bates experimental experimental ex ex- road rood was constructed 1 by bythe bythe bythe the division of ot highways Illinois department department de de- de of public wo works s and nd build build- i ings in co operation with the Dureau bureau of public roads United States Department Department Depart Depart- ment meat of ot Agriculture Actual work was waR q h n na a r y yi i Instrument Set Up for Obtaining In Information Information lri- lri formation on an Deflection of Pavement Showing Method of Loading A Anes 9 Dial and Apparatus for Rece Receding Pressure Cells Ceils I I t begun on the road in June l 1020 O rand find It was finished some time ago Since Its completion the state and federal government engineers by numerous us daily dally observations have been measurIng measuring I Ing the effect t of ot heat cold moisture and other elements upon Its surface and on the These observations have bet been bean n taken on 63 03 sections and much Information has hns been obtained ob ob- obtained which will be valuable in building building build Jd ing roads In the future This Inform Information is of ot the utmost value Knowing the conditions of ot traffic which are to be met It will wUl afford af at- afford ford Cord a means by b- which a proper paving pacing can cnn be select selected d to meet those con con- on- on It may lead to the saving of ot millions of ot dollars each cach year ear by preventing preventing pre pre- venting the construction of pavements that are arc found to he Incapable of ot resisting resisting resisting re re- re- re modern traffic Why some types of pavement failand falland fall fail and others hold up will ill be laN largely ly determined by the test Why a roadway roadway road road- way cracks also I Is b being studied At different times ea each section Is observed ed and all cracks noted In addition a considerable number of ot cracks have bave been measured by a Q micrometer |