Rockfall has been reported along about 3000 miles of California highways. Information was obtained by means of a questionnaire sent to California Department of Transportation maintenance personnel and by field examination of 92 locations. Information contained in the questionnaire was used to examine the causes of rockfall in California, identify corrective methods that are used, and determine the effectiveness of these mitigation measures. Additional information on rockfall mitigation was obtained from a literature search and from correspondence with fourteen State Transportation Departments and with transportation systems in Canada, Switzerland, and France. The data from California sites show that rain is listed as a cause of rockfall at all 92 sites. Glacial material and volcanic mudflows are common sources of rockfall in the State. Wire mesh fences are widely used in California to control rockfall. The effectiveness of these fences is dependent upon the use of design criteria developed by the Washington State Department of Transportation. A flow chart has been developed for use in choosing effective mitigation measures. These corrective methods are described in an appendix to the report.

Media Info

  • Pagination: 147 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00457920
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA/CA/TL-85/12, 54322-632173
  • Contract Numbers: F76TL12
  • Created Date: Sep 30 1987 12:00AM