Mechanical improvement of concrete by irradiated polypropylene fibers

Abstract

Fiber reinforced concrete (FRC) contains fibers physically mixed with gravel, sand, cement, and water. So far, adequate mechanical performance of FRC has been obtained at high cost and using complex technologies; important here is the geometry and surface characteristics of the polymers. We have modified polymeric‐fiber surfaces by using gamma radiation. Irradiated polypropylene (PP) fibers were submitted to 0, 5, 10, 50, and 100 kGy of gamma irradiation dosages. First, tensile strength of PP fibers was evaluated, and then fibers blended at 0, 1.0, 1.5, and 2.0% in volume with Portland cement, gravel, sand, and water. The highest values of compressive strength were obtained with irradiated‐fibers at 10 kGy and 1.5% in volume of fiber. The result is 101 MPa, as compared to 35 MPa for simple concrete without fibers. POLYM. ENG. SCI., 45:1426–1431, 2005. © 2005 Society of Plastics Engineers

Compressive strength of gamma‐irradiated polymer concrete

“…Under irradiation with gamma particles, we observe crack formation of the resin and the separation between sand particles and resin, what causes changes in the mechanical properties. This work is part of a larger project focused on the effects of the gamma radiation on polymers and concrete, including hydraulic and PC [20,21].…”

Durability properties of concrete reinforced with steel-polypropylene hybrid fibers

“…The fi brillation increases the surface contact area and enhances mechanical anchoring to the matrix, as well as improving the fi ber modulus. Both techniques are particularly suitable for polymeric fi bers, due to their low strength and large strain capacity [26] .…”

Post-irradiation effects on gamma-irradiated nylon 6,12 fibers

“…In addition to the basic research relevance of such studies, nylons have very attractive properties, such as excellent toughness, high tensile strength, abrasion resistance, chemical resistance, dimensional stability, excellent wet strength retention, and low tissue reaction [1]. By contrast, there is great interest in studying the radiation stability of polymers [2], as well as the change in chemical, mechanical and physical properties [3], aiming for future applications [4][5][6][7]. However, relatively few reports have been published on the effect of gamma radiation on nylons: mechanical properties [8], melting point decrease [9,10], degree of crystallinity [11][12][13], surface modification [14,15] and additional polymerization [9].…”