OCR Text |
Show FIND DEFECTS IN PAVEMENT Examination Being Mado of Asphalt and Bituminous Concrete for Cause of Spots. Samples of sheet asphalt paving from five large cities are being examined exam-ined in the laboratory of the bureau of public roads, United States Department Depart-ment of Agriculture, to determine, if possible, the cause of the formation of bad spots and waves, or corrugations. A few samples of bituminous concrete are also being examined. The samples sam-ples have been cut both from good and bad sections of the same-pavlng job and are examined for appearance of sample, grading of aggregate, and quantity and characteristics of asphalt. Although a separate Investigation from the traffic test on the circular track made of sections of bituminous concrete it Is thought that each Investigation Investi-gation may yield Information helpful to the other. |