Progress Report No. 5 on Skid Resistance Study U.S. 31 Test Road

A Laboratory Investigation of Factors Affecting the Slipperiness of Bituminous Paving Mixtures

“…The National Safety Council reports in their 1957 edition of "Accident Facts" that during 1956 more than 40,000 persons lost their lives in traffic accidents on the streets and highways of America. In that same period, an additional 1,400,000 motorists and pedestrians received traffic injuries which were disabling beyond the day of the accident .…”

“…By rolling the specimen again at 140 F. for a short time with the conical rollers, a very light asphalt film could be made to coat the aggregate.This coating discolored the aggregate somewhat, but did not result in a solid bleck asphalt appearance, so seemed more representative of an oily rather than en ssphaltic film. It was felt that although this treatment did not exactly duplicate the oil drippings, worn rubber, and debris film that exist on highways during certain seasons of the year(25,40), the relative resistance values for this final condition would be indicative of the susceptibility of the surface types,as represented by the test specimens, to this seasonal effect.…”