In today’s market, it is imperative to be knowledgeable and have an edge over the competition. ACI members have it…they are engaged, informed, and stay up to date by taking advantage of benefits that ACI membership provides them.
Read more about membership
Become an ACI Member
Founded in 1904 and headquartered in Farmington Hills, Michigan, USA, the American Concrete Institute is a leading authority and resource worldwide for the development, dissemination, and adoption of its consensus-based standards, technical resources, educational programs, and proven expertise for individuals and organizations involved in concrete design, construction, and materials, who share a commitment to pursuing the best use of concrete.
American Concrete Institute
38800 Country Club Dr.
Farmington Hills, MI
Chat with Us Online Now
Feedback via Email
Home > Publications > International Concrete Abstracts Portal
The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.
Title: Study of the Interface Strength in Steel Fiber-Reinforced Cement-based Composites
Author(s): Sun Wei, James A. Mandel, and Samir Said
Publication: Journal Proceedings
Appears on pages(s): 597-605
Keywords: acrylic resins; bonding; cements; metal fibers;microcracking;microhardness; mortars (material); pullout tests; strength.
Abstract:The properties of fiber-reinforced cement-based composite materials are dependent on the characteristics of the fiber, the matrix, and the fiber-matrix interface. In general, the nature and behavior of the fiber and matrix are reasonably well understood, but those of the interface are known in considerably less detail. Results of an experimental program demonstrate that the addition of an acrylic polymer to fiber-reinforced mortar and cement strengthens the matrix material and improves the structure of interface, thus increasing the interface bond strength. Tensile tests, fiber pullout tests, microhardness studies, and electron microscopy studies were conducted on mortar matrix materials, with and without the addition of the acrylic polymer. The tensile strength of the matrix material, the interfacial bond strength between the matrix and steel fibers, and the energy required for fiber debonding and pullout were increased by a factor of almost four with the addition of 15 percent acrylic polymer by weight of cement. To explain these increases, the microhardness and microstructure of an annular region of the composite surrounding a fiber (interface transition ring) were investigated. Addition of the acrylic polymer to a cement matrix resulted in increases in microhardness of the cement-matrix material of the same order of magnitude as increases obtained in tensile strength, bond strength, and energy required for fiber debonding and pullout. Observation with a scanning electron microscope indicated that cracking along the fiber-matrix interface (before loading) is substantially reduced by the addition of acrylic polymer. Possible explanations for this are a reduction in the film of water that surrounds the fiber and the filling of small cracks with the acrylic polymer material itself.
Click here to become an online Journal subscriber