Evaluation of 1977 Asphalt Concrete Sprinkle Treatments, December 1980

Iowa's first sprinkle treatment in 1974 was applied to a short section of old US 30 west of Ames. A roll type seal coat spreader was used to apply several types of sprinkle aggregates. The following year a spinner type tailgate spreader was used for sprinkle application of an Iowa 7 project in Webster County. Uniform spreading and tire marks were problems in these early projects. A special spinner spreader was built in 1976 and mounted on a truck specially equipped with smooth tires. This special unit was tested in early 1977 on a project that had been scheduled for 1976. Spinner type spreaders proved unacceptable due to non-uniformity of spreading.

[Phot. des membres de la mission envoyée à l'île Saint-Paul pour y observer le passage de Vénus en 1874, don de Charles Vélain. Il s'agit en réalité de la reproduction d'un cliché offert par Ernest Mouchez à Auguste Daubrée]

Donateur : Daubrée, Auguste (1814-1896)