Performance of fibers embedded in a cementitious matrix

Abstract

Reinforcement of cementitious materials with short fibers has been proved to be an economical and effective way to convert these brittle materials to ductile products. Many fibers with different geometries have been used as reinforcement materials. Fibers bonding to cementitious materials play an important role in mechanical performance of these composites. This article describes the performance of (homemade) fibers as reinforcement in cement-based materials by investigation on bonding characteristic of fiber to cement matrix. To this end, the fibers (glass, polypropylene, polyacrylonitrile (PAN), and high strength nylon 66 (N66)) are characterized using microscopy analysis, tensile strength, and alkali attack tests. The fibers embedded in the cement matrix, then, pulled-out to evaluate their bonding to cementitious materials. SEM analysis is used to study fiber/cement interfacial transition zone. The results show that PAN fibers have the advantages of preparing for cementitious reinforcement. It was found that the reinforcing efficiency of fibers-reinforced cementitious composites was strongly depending on interfacial contact area in fiber/matrix interface and chemical/physical properties of fibers.

The effect of hybridization and geometry of polypropylene fibers on engineered cementitious composites reinforced by polyvinyl alcohol fibers

“…23,24 Both triangular and trilobal fibers have a shape factor (S.F.) more than 1 which is in favor of attaining high mechanical interlocking with the surrounding matrix.…”

Interfacial bonding of fine aggregate concrete to low modulus fibers

“…The wet spun Acrylic fiber has shown better performance in bonding to the cementitious materials in comparison to the dry spun fiber [10,21]. To assess the accurate dimensions of the non-round fibers, the image processing software that allows segmenting the cross section of the fibers was employed.…”

“…The high and very low fiber/matrix interface strength leads to a tendency of fiber rupture and easy fiber pull-out, respectively, which limits the tensile strain capacity and energy absorption of the resulting composite. It has been found that low modulus polymeric fibers generally result in strain softening behavior due to their low tensile capacity [10,[20][21]29].…”

“…Based on previous researches [8][9][10], Nylon 6,6 and Acrylic fibers due to their higher bonding to cementitious materials and good dispersion in the matrix are selected as the most promising low modulus fibers.…”

Utility of polyvinyl alcohol fiber-based needle punched nonwoven fabric as potential reinforcement in cementitious composites

“…15 Although PP and PE fibers have hydrophobic characteristics and poor bonding with the cement matrix, these fibers are considered to be attractive for the reinforcement of cement matrices due to their high resistance to the alkaline environment of the cement matrix ($12.5 pH) and their low cost. 6,12 Pakravan et al 7 examined the performance of different fibers such as glass, polypropylene, polyacrylonitrile (PAN) and high-strength nylon 66, used as reinforcement for cement-based composites. It was reported that the reinforcing efficiency strongly depended on interfacial contact area in fiber/matrix interface and chemical and physical properties of fibers.…”