Produção, caracterização e avaliação da durabilidade de compósitos cimentícios com partículas de pó de coco

Abstract

This study aimed to develop cementitious composites with the addition of coir pith particles (CCC). Initially the feasibility of use coir pith particles as a replacement of fine aggregates for the production of composites was evaluated. Chemical treatments were conducted on coir pith particles to improve the compatibility with Portland cement. Cement composites were produced with the treated particles in order to evaluate the influence of pre-treatment on the physical and mechanical properties of the composites. Subsequently, the effect of coir pith particle size in physical and mechanical properties of the composites was evaluated. Composites durability was measured by methods of external and internal natural aging for up to 6 months and accelerated aging in a chamber of UV and condensation for up to 180 cycles. From the overall results, using coir pith particles as a total substitute of sand in cementitious composites was possible. The addition of coir pith particles to cement paste resulted in changes in mechanical and physical properties of composites. The composites produced had an apparent density and mechanical strength that allowed their use as lightweight construction materials. The chemical treatments of coir pith particles with alkaline pH and the decrease of the coir pith particle size positively influenced the compatibility with cement and the composites had higher strength and they were denser, compared with the composites with in natura and "as received" particles. For the evaluation of durability, the composites with treated particles also had a better performance and the results from internal natural aging procedure indicated the use of these composites as material for production of non-structural building elements for interior walls.