This article reports the results of a study related to the reinforcement of mortar-based composites with newly developed polyethylene/polypropylene blended fibers. The study showed the hybrid fibers to have a mechanical/reinforcing effect in the cement-based matrix. Mechanical strengths improvements, as high as 40 ± 2%, were obtained for composites with a fiber length of 24 mm and a fiber volume fraction of 2.9%.
The mechanical enhancement was associated with a strong mechanical interlocking between the fibers/cement matrix interfaces promoted by the fibers’ surface ridges and fibrillation ability. Macro/microstructure and morphological observations showed a post-cracking ductility improvement of composites by the hybrid (bridge effect) fibers, also evidenced a multi-cracking mechanism.
KayaliOKhatibJM. Concrete sustainability and the role of fiber reinforcement. the international symposium on innovation and sustainability of structures in civil engineering, China: South China University of Technology, 2009, pp. 148–153.
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