Determining Triaxial Tensile Strength of UHPC with Varying Fiber Contents

  • Trevor Looney (U.S. Army Engineer Research and Development Center)
  • Jeffery Volz (University of Oklahoma)


The tensile strength of conventional concrete is often ignored in structural design due to its relative low value when compared to compressive strength. However, when designing ultra-high performance concrete structures, ignoring tensile strength is overly conservative and could lead to inefficient designs. Uniaxial tensile data is available for UHPC mix designs, but very little data exists examining the multiaxial tensile strength of the material. To help fill this data gap, an apparatus was designed at the University of Oklahoma capable of applying multiaxial tensile stress states to a cube specimen. A UHPC mixture developed at the University of Oklahoma with fiber contents of 0%, 1%, 2%, 4%, 5%, and 6% by volume was characterized in this apparatus to assess the effect varying the fiber content had on its multiaxial tensile strength. The data collected was compiled and compared to previously published multiaxial compressive UHPC data. This dataset was then used to fit two previously published models with different meridian shapes (parabolic and cubic) to ascertain which shape best describes the failure criteria of UHPC in the tensile region. It was found that triaxial tensile strengths decreased as the fiber dose increased over 4%. Also, the combined dataset fit a cubic meridian shape more closely than parabolic.

Keywords: UHPC, multiaxial tension, triaxial tension, tension-tension-compression, failure model, failure criteria

How to Cite:

Looney, T. & Volz, J., (2023) “Determining Triaxial Tensile Strength of UHPC with Varying Fiber Contents”, International Interactive Symposium on Ultra-High Performance Concrete 3(1): 101. doi:

Rights: © 2023 The Author(s). All rights reserved.

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Published on
04 Jun 2023
Peer Reviewed