| Abstract Scope |
Natural lignocellulosic fibers are promising reinforcements for mineral-based composites, but their effectiveness depends on the mechanical condition of the matrix. This study evaluates the cementation-dependent response of a clayey soil reinforced with untreated piassava fiber (Attalea funifera Mart.) under repeated loading. Fibers were added at 0, 0.5, and 1.0% by dry soil mass, while Portland cement was incorporated at 0, 2.0, and 3.5%, resulting in nine formulations. Fiber morphology was examined by scanning electron microscopy, and mechanical performance was assessed through repeated-load triaxial tests over 100,000 cycles. The fiber surface was heterogeneous and rough, indicating potential for frictional interaction and mechanical interlocking. In the uncemented matrix, 0.5% fiber reduced permanent deformation by approximately 55%. At 2.0% cement, 1.0% fiber produced the lowest deformation, whereas at 3.5% cement the response was mainly governed by the cemented matrix. These results highlight the combined influence of fiber content, compactability, and matrix cementation. |