Abstract

Waste valorization has entered the construction industry over the last decades, and the use of waste to replace components and/or improve properties of cement-based materials has been attracting research attention world-wide. Cement-based materials perform well under compression, but their tensile strength and post-cracking ductility in tension are poor and plastic shrinkage cracking is still a significant problem. Fibers produced from steel, glass and synthetic materials, have been successfully used to overcome some of these shortcomings, but the use of waste-valorized fibers as reinforcement to cement-based materials has had limited research. This investigation addresses the physical-mechanical characterization of pig hair, which is a waste produced by the food-industry worldwide, and fiber-reinforced mortars incorporating pig hair. This composite material is intended to reduce the environmental impacts by valuing waste materials in construction applications while improving its mechanical and durability properties. This study performed laboratory tests to estimate physical properties of pig hair such as lengths, diameters, aspect ratios, and water absorption as well as the mechanical property of tensile strength. The results show mean values of length, diameter and aspect ratio of 36 mm, 0.16 mm and 249, respectively. The estimation of water absorption was 95% and the mean tensile strength reached 99 MPa. To determine compressive, flexural and impact strengths, age at cracking and resulting crack widths, laboratory tests were conducted in mortar specimens with 0, 2, 4 and 8 kg of pig hair per m3 of mortar. The results show up to a 16% increment in the flexural strength and a 12% reduction in the compressive strength when pig hair is incorporated to mortars. The impact strength, indicator of toughness, can increase up 55% when compared to plain mortar and the age at cracking and resulting crack widths, indicator of durability, are also improved when pig hair is incorporated.