Development of a Rock Strength Database

Rock strength and elastic behavior are important for foundations such as spread footings resting on rock and drilled shafts socketed into rock. In addition to traditional rock quality information, stiffness and failure parameters are helpful for design. The Minnesota Department of Transportation (MnDOT) has previously used a low-capacity load frame for routine rock testing but this apparatus does not generate sufficient force for testing hard rock. The report provides a comprehensive suite of results from 134 specimens tested under uniaxial compression and 33 specimens tested under triaxial compression on a wide variety of rock, including hard rock, which frequently is of interest for high-capacity foundation systems. Thus, an economic benefit is realized if the strength of the rock is measured, as opposed to correlated with an index parameter, due to the potential to reduce foundation size and construction time. Information from the testing was used to expand the MnDOT database of rock properties and allow for improved designs based on accurate measurements of Young’s modulus, uniaxial compressive strength, and friction angle.

  • Record URL:
  • Record URL:
  • Corporate Authors:

    University of Minnesota, Twin Cities

    Department of Civil, Environmental, and Geo-Engineering
    500 Pillsbury Drive, SE
    Minneapolis, MN  United States  55455-0116

    Minnesota Department of Transportation

    Research Services and Library
    395 John Ireland Boulevard
    St Paul, MN  United States  55155
  • Authors:
    • Folta, Brian
    • Sharpe, Jacob
    • Hu, Chen
    • Labuz, Joseph
  • Publication Date: 2018-6


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 233p

Subject/Index Terms

Filing Info

  • Accession Number: 01677310
  • Record Type: Publication
  • Report/Paper Numbers: MN/RC 2018-19
  • Contract Numbers: 99008 (wo) 165
  • Created Date: Jul 27 2018 8:28AM