Title:
Studies of the Properties of the Fiber-Matrix Interface in Steel fiber Reinforced Mortar
Author(s):
James A. Mandel, Sun Wei, and Samir Said
Publication:
Materials Journal
Volume:
84
Issue:
2
Appears on pages(s):
101-109
Keywords:
acrylic resins; bonding; metal fibers; microcracking; microhardness; mortars (material); plastics, polymers, and resins; pullout tests; strength; stiffness; Materials Research
DOI:
10.14359/1815
Date:
3/1/1987
Abstract:
The properties of the interface between the fiber and matrix material have a significant effect on both the strength and toughness of a fiber reinforced composite. To model fiber debonding, it is necessary to determine the coefficient of adhesion between the fiber and the matrix material. A procedure was developed to determine the coefficient of adhesion, the energy release rate per unit area of crack surface at the crack front required for unstable growth of a crack along the fiber-matrix interface. This procedure utilizes the results of a fiber pullout test and finite element analyses of the pullout test. Interface properties between a straight steel fiber and two matrix materials (mortar both with and without polymer) were investigated. For a given fiber spacing, values of the coefficient of adhesion for a mortar matrix material with polymer were shown to be significantly higher than those for the mortar matrix without polymer. The average interface bond strength and the average interface bond stiffness for a matrix material with 10 percent by weight of cement of polymer were shown to be approximately twice the values measured using a mortar matrix without polymer. The energy required for fiber debonding and pullout was also approximately doubled by adding 10 percent by weight of cement of the polymer.