Title: Behavior of Fiber Reinforced High-Strength Concrete Under Direct Shear

Author(s): Mariano Valle and Oral Buyukozturk

Publication: Materials Journal

Volume: 90

Issue: 2

Appears on pages(s): 122-133

Keywords: fibers; high-strength concretes; polypropylene fibers; shear strength; shear stress; Materials Research

DOI: 10.14359/4006

Date: 3/1/1993

Abstract:
This paper reports the results of an investigation on the strength and ductility of fiber reinforced high-strength concrete under direct shear. Both experimental and modeling studies were performed. In the experimental study, fiber reinforced high-strength concrete push-off specimens were tested. Two types of fibers, polypropylene and steel fibers, in conjunction with or without conventional stirrups were used. An existing model was developed further and used in the analytical prediction of the shear stress-strain relationships for these specimens. In general, fibers proved to be more effective in high- strength concrete than in normal strength concrete, increasing both ultimate load and overall ductility. This is attributed to the improved bond characteristics associated with the use of fiber in conjunction with high- strength concrete. For the specimens with steel fibers, significant increases in ultimate load and ductility were observed. With polypropylene fibers, a lower increase in ultimate load was obtained compared to the increase due to steel fibers. Ductility of the polypropylene fiber reinforced specimens was greater than that of the steel fiber reinforced specimens. In the tests involving the combination of fibers and conventional stirrups, there were slight increases in ultimate load while major improvements in ductility were observed, in comparison to the values for plain concrete specimens with conventional stirrups. In general, good agreement between the model and the test results was found.