Title: Cylinder or Cube: Strength Testing of 80 to 200 MPa (11.6 to 29 ksi) Ultra-High-Performance Fiber-Reinforced Concrete

Author(s): Benjamin Graybeal and Marshall Davis

Publication: Materials Journal

Volume: 105

Issue: 6

Appears on pages(s): 603-609

Keywords: compressive strength; cube; cylinder; ultra-high-performance fiber-reinforced concrete

DOI: 10.14359/20202

Date: 11/1/2008

Abstract:
Accurate determination of the compressive strength of very high strength concrete is currently a difficult proposition due to large testing machine capacity requirements and the need for cylinder end preparation. An experimental program was conducted to determine whether alternate specimen types can be reliably used to determine the compressive strength of an ultra-high-performance fiber-reinforced concrete (UHPFRC) in the strength range from 80 to 200 MPa (11.6 to 29 ksi). Fifty-one, 76, and 102 mm (2, 3, and 4 in.) cylinders were tested alongside 51, 70.7, and 100 mm (2, 2.78, and 4 in.) cube specimens. The 76 mm (3 in.) cylinder as well as the 70.7 and 102 mm (2.78 and 4 in.) cubes were found to be acceptable alternatives to the standard 102 mm (4 in.) cylinder specimen. The 70.7 mm (2.78 in.) cube specimen is recommended for situations where machine capacity and/or cylinder end preparation are of concern.