TUFA PRECIPITATION AND ITS EFFECT ON DRAINAGE OF HIGHWAY PAVEMENT

Calcareous tufa has been observed occluding drain outlets and catch basins as well as covering slopes at 124 localities in Cuyahoga, Portage, Summit, and Medina counties in northeastern Ohio. Regional geologic studies, hydrogeologic studies, and geochemical analysis have been employed to identify the source and mode of origin of the material which prevents highway drainage systems from functioning properly. No correlation was found between regional geologic and hydrogeologic conditions analyzed. Geochemical analysis of water collected from subbase drain outlets and of an array of construction materials leads to the conclusion that slag, when used as a subbase material, is sufficiently soluble to affect the pH of drainage water and to provide the calcium deposited as tufa. Solution of calcium hydroxide in slag in the subbase elevates the pH of drainage water above 10 and creates an environment in which CaCO3 can be precipitated. The problem of tufa deposition will continue in northeast Ohio as long as slag is used as a subbase material. However, careful maintenance of the highway surface to reduce the amount of water entering the drainage system through edge joints and fractures in the pavement will significantly reduce the magnitude of the problem. (FHWA)

  • Corporate Authors:

    Kent State University

    Department of Geology
    Kent, OH  United States  44242

    Ohio Department of Transportation

    25 South Front Street
    Columbus, OH  United States  43215

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Feldmann, R M
  • Publication Date: 1981-7

Media Info

  • Pagination: 147 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00345081
  • Record Type: Publication
  • Report/Paper Numbers: FHWA/OH-81/010 Final Rpt.
  • Contract Numbers: 14338(0)
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Jan 29 1982 12:00AM