Effect of curauá fibers inclusions on the mechanical behavior of a sandy soil
Mariana Vela Silveira1; Michéle Dal Toé Casagrande1
1 Pontifícia Universidade Católica do Rio de Janeiro
Baixar PDF doi:10.20906/CPS/CB-01-0044
Resumo
Soil reinforcements with synthetic and vegetal fibers have been widely studied. It is already known that the inclusion of fibers increases the peak resistance and decreases the post-peak resistance drop of non-cohesive soil under static load. However, the improvement or the alteration of mechanical properties of soil reinforced with fibers depends on the characteristics of the fibers (tensile strength, modulus of elasticity, length, content and surface roughness), of the soil (degree of cementation, size, shape and granulometry of particles and voids), of the type of inclusion (randomly distributed or in the form of layers), the confinement stress and the loading mode. This experimental study reports the behavior of a reinforced and unreinforced granular soil with the addition of short curauá fibers randomly distributed. These fibers are extracted from the leaves of plants of the Ananas erectifolius species, which are a naturally occurring bromeliads in the Amazon. These vegetal fibers were chosen because they have good mechanical properties. Conducting studies employing curauá fibers as soil reinforcement has the main objective to know their behavior aiming to be a sustainable alternative to replace the synthetic fibers used for the same purpose. The curauá fibers were mixed with granular sandy soil to evaluate its influence on the mechanical properties of the soil. A series of compression isotropic drained triaxial test was performed to seek to establish patterns of behavior that might explain the influence of the addition of curauá fibers, relating it to the shear strength and deformation parameters of the soil. The tests were performed on samples subjected to a relative density of 50 % and moisture content of 10 %, fibers content in proportions of 0 and 0.5 % of the dry weight of the soil and the fibers lengths of 25 and 50 mm. As a natural fiber, its diameter is not constant. Through the obtained results, it was observed that the addition of curauá fibers randomly distributed leads to significant improvement
Palavras-chave: Natural fibres; soil reinforcement; granular soil