The Boulevard of the Allies is a major four-lane roadway located in the City of Pittsburgh, Pennsylvania. The roadway was initially constructed in the 1920s at the edge of a near vertical, 115-ft high rock slope locally known as the Duquesne Bluff. In addition to normal traffic flow, the Boulevard of the Allies currently serves as a major detour route for an ongoing bridge and tunnel reconstruction project. In anticipation of the increased service of the roadway, the Pennsylvania Department of Transportation completed an in-depth rehabilitation prior to the bridge and tunnel closure. This effort included the widening of the roadway and reconstruction of four bridge structures along its one-mile length. A primary component of this rehabilitation consisted of the identification of adverse geotechnical conditions and design of corrective measures to stabilize the underlying rock slope, protect the traveling public from future geologic hazards, and facilitate the proposed construction activities. These concerns included: the presence of several adversely oriented discontinuity sets leading to potential rock block instability; differential weathering resulting in potentially unstable rock masses; and the mass wasting of the rock slope causing the loss of bearing support at structure locations. To remedy these conditions, construction activities consisted of: extensive use of rockbolts to secure rock blocks along adversely oriented discontinuities; reconstruction of cantilevered roadway sections; installation of pin piles through existing structures to improve the bearing resistance; and the construction of slope netting as well as a rockfall retention fence.

  • Supplemental Notes:
    • Unlike most groups and organizations that meet on a regular basis, the Highway Geology Symposium has no central headquarters, no annual fees, and no formal membership requirements. The governing body of the Symposium is a Steering Committee. Recent proceedings may be obtained from the Treasurer of the Symposium, Mr. Russell Glass.
  • Corporate Authors:

    Mr. Russell Glass

    100 Wolf Cove Road
    Asheville, NC  United States  28804
  • Authors:
    • Kovacs, J W
    • Morris, M B
    • Schultz, J W
  • Conference:
  • Publication Date: 2002


  • English

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 159-170

Subject/Index Terms

Filing Info

  • Accession Number: 00962020
  • Record Type: Publication
  • Report/Paper Numbers: CD-ROM
  • Files: TRIS
  • Created Date: Aug 8 2003 12:00AM