Strut-and-Tie Modeling and Design of Drilled Shaft Footings

The design and detailing of reinforced concrete footings supported by a grid of drilled shafts varies greatly on a state, district, and even municipality basis. The Texas Department of Transportation (TxDOT) has attributed the variations to a lack of guidance and standards for the design of shaft-supported footings. Refinement of the two-dimensional strut-and-tie (STM) provisions of TxDOT Project 0-5253 will provide the guidance necessary for consistent design of three-dimensional column footings. Straightforward Design Provisions for Strong, Serviceable Footings: Nodal efficiency factors and reinforcement anchorage requirements are to be derived on the basis of largescale testing and analytical studies. It is anticipated that recommended design process will consist of stress checks at singular bearings and anchorage checks at critical locations of the STM. Optimal Strut-and-Tie Models for Common Load Combinations: A set of generalized strut-and-tie models are to be developed for the most common load combinations encountered by TxDOT. Empirically based guidance will accompany the generalized strut-and-tie models to ensure the most efficient placement of model elements. Implementation of the three-dimensional STM guidelines developed during TxDOT Project 18-60 will lead to the construction of highly efficient, durable shaft-supported footings across the State of Texas.


  • English


  • Status: Completed
  • Funding: $999126
  • Contract Numbers:


  • Sponsor Organizations:

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483
  • Project Managers:

    Steele, Joanne

  • Performing Organizations:

    Center for Transportation Research

    University of Texas at Austin
    1616 Guadalupe, Suite 4.202
    Austin, TX  United States  78701
  • Principal Investigators:

    Bayrak, Oguzhan

  • Start Date: 20170901
  • Expected Completion Date: 20201231
  • Actual Completion Date: 20210531

Subject/Index Terms

Filing Info

  • Accession Number: 01648610
  • Record Type: Research project
  • Source Agency: Texas Department of Transportation
  • Contract Numbers: 0-6953
  • Files: RIP, STATEDOT
  • Created Date: Oct 20 2017 10:21AM