Multifaceted Approach for Evaluating and Treating Sinkhole Activity Beneath Highways – Case Study: SR 0422 in Southeastern Pennsylvania

In the overnight hours between September 30th and October 1st, 2010, several sinkholes developed along a heavily-traveled section of SR 0422 in southeast Pennsylvania. In conjunction with PENNDOT’s geotechnical engineers, Gannett Fleming developed a sinkhole investigation program to identify the likely sources of the sinkhole activity amid the busy highway environment. The sinkhole investigation program consisted of a multifaceted approach incorporating three different geophysical survey methods; test borings within the travel lanes, shoulders, and median; a comprehensive review of available geologic data, including previous test borings performed adjacent to the investigation area; a visual pavement condition assessment; and visual and survey monitoring of the ongoing sinkhole and subsidence related activities across the site. The geology of the project site is characterized by a variable bedrock surface consisting of pinnacles, solution cavities, fracture zones, and a localized thrust fault. Using a comprehensive investigation approach allowed for the analysis and consolidation of a large amount of data leading to a more detailed interpretation of the subsurface conditions. Based on the findings, a limited mobility grout program was designed and implemented to address the subsidence features at the site and mitigate future sinkhole activity. Several logistical challenges were encountered during the investigation and subsequent construction phase of the project, including maintenance of traffic, limited work zone areas, and time constraints. Sinkhole activity in the carbonate belt of southeastern Pennsylvania is not unfamiliar to engineers and geologists, however, when sinkholes occur in a heavily-traveled highway corridor, they present unique challenges for investigation and remediation


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Photos; References;
  • Pagination: pp 297-314
  • Monograph Title: Proceedings of the 63rd Annual Highway Geology Symposium (HGS 2012)

Subject/Index Terms

Filing Info

  • Accession Number: 01661550
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Feb 22 2018 11:36AM