| OCR Text |
Show SCIENTIFIC ROAD BUILDING Test Being Made In Illinois to Determine De-termine What Pavement Can Be Used on Highways. (Prepared by the United States Department of Agriculture.) Some time within the next few months a new road 2 miles long is to be broken up In what is probably tho most extensive study of roud Borvlce ever undertaken in the United. States. The road is located In Illinois, about Hi miles southwest of Sprlngtleld, and parallels the Waush railroad. In the test road there are no curves. The grades vary from zero to four-tenths of 1 per cent, with an averago grade of one-tenth vt 1 per cent, the maxlmuu and minimum grades 'extending over Very short distances. The subgrude siU Is uniformly n brown silt loam, except for two small stretches whero it more nearly approaches gumbo. There .arc seven general types of DAT-lag DAT-lag in the road, the idea being lo have represented the chief materials used In road making, so that "engineers may study the effect of known und measured trnfllc of varying degree upou each kind of road. The seven types arc: Portland cement concrete. Three and fo'ur Inch lug brick constructed con-structed monolithic and with n Portland Port-land cement concrete base. Three and four inch lug brick constructed con-structed seihlmonollthlc and with ft Portland cement concrete base. Thtcc and four inch bituminous tilled lug and lugless brick on Portland cement ce-ment concrete base. Three nnd four inch bituminous llllod lug nnd lugless brick on macsdaui base. Asphnltic concrete with and without binder course on macadam base. The road, known as the Bates experimental ex-perimental road, was constructed by the division of highways, Illlnoli department de-partment of public works and buildings, build-ings, In co-operation with the bureau of public roads, United States Department Depart-ment of Agriculture. Actual work wns j j. Instrument Set Up for Obtaining Information In-formation on Deflection of Pavemt'nt, Showing Method of Loading Ancs Dial and Apparatuo for Receding Presaure Cells. begun on tho road In June, 1020, nnd It was finished some time ago. Since its completion the state nnd federal government engineerSi by numerous dnlly observations, have been measuring measur-ing the effeet of heat, cold, moisture, and other elements upon Its surface and on the wibgrnde. These obsen'n-tlous obsen'n-tlous have been taken on 03 sections, and much Information has been obtained ob-tained which will be valuable In building build-ing roads In the future. This information Is of the utmost value. Knowing the conditions of trufllc which are .to be met, It will nf-iford nf-iford a means by which a proper pacing enn bo selected to meet those conditions. con-ditions. It mny lend to the siiYtni; of millions of dollars each year by preventing pre-venting the construction of pavement thnt nrc found to be Incapable of resisting re-sisting modem traffic. Why some types of pnvement fall and others hold up will be largely determined by the test Why a roadway road-way wacks also Is being studied. At dlfferemt times each section Is observed and a 11 cracks noted. In addition, a considerable number of cracks have been measured by n micrometer. |
