INDUCED MODIFICATION OF FLEXURAL TOUGHNESS OF BIO-LIME BASED MORTARS BY ADDITION OF GIANT REED FIBERS

Fibers are often used as reinforcement of brittle materials, like mortars, in order to modify their mechanical behavior; particularly the modification in post-cracking toughness, induced by low elasticity modulus fibers in the artificial stone material, is the main goal in natural fibers mortar manufacturing. In this work Arundo donax L. fibers are used to reinforce lime mortars according to the characteristics of this plant, very commonly available and with high mechanical properties, similar to bamboo, traditionally used in buildings in Spain. Influence of fibers’ length and weight ratio is studied. Particularly, three different fibers’ lengths, 4, 8 and 12 centimeters, and three weight ratio, 0.5, 1 and 2% are used. The experimental characterization focused on bending and compression tests on mortars’ samples as well as tensile and pull out tests on single fiber. Overall, according to experimental results, mechanical flexural properties of the mortar are significantly improved by the addition of natural fibers at different weight contents and lengths, optimal fibers’ weight ratio and length was individuated.