Investigation and Guidelines for Drilled Shaft Excavation Inspections

A proper drilled shaft (a.k.a. caisson) excavation inspection is crucial to the structural integrity of the shaft. Factors such as irregularities on the sidewalls, verticality of the shaft, and debris on the shaft bottom play an important role in the constructability and the structural performance of the shaft under service loads. In the case of a dry shaft construction, the field inspector may visually assess the walls and base of the drilled shaft by entering the excavation. An entry into a drilled shaft requires compliance with Occupational Safety & Health Agency (OSHA) requirements, which may include testing for toxic and flammable gases. Due to such safety concerns, field inspectors have been reluctant to carry out such inspections. In this study, a range of drilled shaft excavation inspection equipment with the capability to eliminate sending a human into the dry shaft excavation has been investigated. Equipment varies in size, cost and technology. The field effectiveness of several equipment types was evaluated during field demonstration events. Important aspects of all equipment and field observations have been summarized in tables to serve as a guideline for equipment selection decisions. Finally, equipment selection recommendations have been made based on six criteria: safety, cost, mobility, accuracy, speed, and state DOT experience.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Maps; Photos; References; Tables;
  • Pagination: 150p

Subject/Index Terms

Filing Info

  • Accession Number: 01780543
  • Record Type: Publication
  • Report/Paper Numbers: GDOT-GA-21-1907, 19-07
  • Contract Numbers: KSURV-431550; GDOT PI#16890
  • Created Date: Aug 27 2021 2:58PM