Using Polyolefin Fibers with Moderate-Strength Concrete Matrix to Improve Ductility

Abstract

Research has shown that polyolefin fiber–reinforced concrete (PFRC) can meet the requirements of standards in terms of the contributions of fiber in structural design. Such results were obtained with fibers embedded in high-performance concrete matrixes. Given that the precracking maximum strength is mainly governed by the matrix properties, a moderate-strength concrete matrix could lead to a reduction in the initial drop of strength after the limit of proportionality. Nevertheless, it was necessary to determine whether residual postcracking behavior would be similar in a poorer matrix. In this study, a moderate-strength concrete matrix with two dosages of polyolefin fibers was produced. The flexural tensile tests showed that it maintained its residual strength and reduced brittleness. All the concrete types tested met the requirements provided in the relevant standards. The study also provides a large comparison with residual strengths found in the literature showing that the contributions of polyolefin fibers were analogous to those cases in which the fibers were embedded in high-performance concrete matrixes. Hence, PFRC is well suited for use in constructive elements designed with low requirements in terms of concrete matrix properties.