Journal of Steel Structures & Construction

the Experimental Fracture Mechanics Single Contoured-Cantilever Beam Specimen

Abstract

David Boyajian* and Tadeh Zirakian

Construction practices involving the rehabilitating, retrofitting, and
reinforcing of concrete structures using fiber reinforced polymer (FRP)
fabrics have been well documented. Experimental efforts to
characterize the effectiveness of this technology, however, have
included many large scale FRP-concrete tests for strength/stiffness
evaluations which do not detect delamination effects; small-scale tests,
on the other hand, only provide average interface strength properties
that neither describe failure mechanisms nor provide fracture
toughness data. In this paper, the experimental fracture mechanics
specimen known as the single contoured-cantilever beam (SCCB) was
used to obtain important quantitative results of FRP-concrete
interfaces as subject to a host of conditions: dry, freezing-thawing,
wetting-drying, fatigue, and surface roughness effects on the integrity
of the interface bond. The findings of this research effort demonstrate
both the importance of surface preparation towards achieving an
optimal bond as well as offering a means of gaging rates of degradation
of the interface under a variety of commonly encountered construction
environments.