Verification of LRFD Resistance Factors for Drilled Shafts Using Field Tests

Project status

In progress

Start date: 06/25/14
End date: 08/31/19


Principal investigators:

Co-principal investigator:

About the research

The overall goal of this proposal is to verify and improve the drilled shaft design (in accordance with the load and resistance factor design (LRFD) framework) and construction procedures used in Iowa, using additional field data and sophisticated analytical methods. This project will use an expanded version of the DSHAFT database. In addition, based on the method proposed in Phase II, a dependable method for extrapolating the 0-cell Load tests will be established for clay, sand, and rock materials. The cost competitiveness of drilled shafts will also be compared.



  • Federal Highway Administration State Planning and Research Funding
  • Iowa Department of Transportation