In 1978, a federally funded project was undertaken which involved remedial work on an existing rock cut located in Manchester, New Hampshire. The through cut consists of Northbound ON and OFF Ramps of Route I-93 at the Wellington Road Interchange. The work included construction of protective measures along both sides of the Northbound OFF Ramp, to restrain, channel and prevent rock-fall from reaching the roadway. These protective measures had to satisfy certain requirements and were subject to several restrictions: nearly maintenance free, minimum of interference to snow plowing operations, year-round protection, easily repairable if damaged, no significant change in the appearance of the existing slope and aesthetically pleasing. A wire mesh blanket, to act as a protective measure, was recommended and installed along the right side of the Northbound OFF Ramp. The mesh, covering the entire rock slope from crest to toe, was recommended for a distance of 925 plus or minus feet. In this section, the rock slope averages 55 plus or minus feet in height with a maximum cut face of 70 plus or minus feet. This portion of the cut has been the site of numerous rockfalls in which a significant number of rocks have reached the roadway. Although the wire mesh has not been in place at this location for a sufficient length of time to evaluate its performance, it has performed very well over extended periods of time, under severe conditions, in other parts of the country and Canada. The wire mesh is quite strong and amazingly flexible. It blends into the slope and has a minimal impact on the environment. The mesh can be used very effectively as a remedial rock fall measure where space is limited for flattening the slopes and other measures can not be used. None of the work performed required any special equipment or expertise by the contractor. All phases of the installation do require a great deal of hand labor. Wire mesh as a protective measure has its place in remedial rock-slope engineering. It is expected that in the future this type of installation may become more widely utilized in North America. (Author)

  • Corporate Authors:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Lane, R M
    • Vanikar, S N
  • Publication Date: 1980-4

Media Info

  • Features: Photos; References;
  • Pagination: p. 1-11
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00324544
  • Record Type: Publication
  • Files: TRIS, USDOT
  • Created Date: Jun 12 1981 12:00AM