Floodwaters of Hurricane Agnes caused the Susquehanna River to wash out about one third of Penn Central's Shocks Mill Bridge. The 66 year old bridge, a 2,200 foot long double track structure, consisted of 28 stone arch spans. An appraisal indicated that foundation scour caused settlement and tilt of Pier 14, one of three heavier anchor piers in the bridge, which disturbed the restraining force against thrust of adjacent spans, and produced a domino effect with adjacent spans collapsing. Reconstruction of the masonry arches would have been too costly and time consuming, and time factors also ruled out through-truss construction. The decision was made to use steel deck girder construction on concrete piers. It was necessary to remove some of the remaining stone arch spans, back to anchor Piers 7 and 21. These piers were strengthened to withstand the thrust from the remaining arch spans. This was done by installing post-tensioned cables down through each pier and into bedrock. These piers were also adapted to serve as abutments for the deck girder spans.

  • Availability:
  • Corporate Authors:

    Simmons-Boardman Publishing Corporation

    P.O. Box 350
    Bristol, CT  United States  06010
  • Publication Date: 1972-12-11

Media Info

  • Features: Photos;
  • Pagination: p. 28-31
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00041145
  • Record Type: Publication
  • Source Agency: Railway Age
  • Files: TRIS
  • Created Date: Mar 23 1973 12:00AM