Impact of content and length of curauá fibers on mechanical behavior of extruded cementitious composites: Analysis of variance

Abstract

The use of composite materials in construction has grown considerably in recent years, such as cementitious matrices and concrete reinforced with fibers. The vegetable fibers have become an alternative due to its abundance, low cost and low energy consumption for its production, and appropriate properties mechanical. Curauá fiber is a plant native from Amazonas harvested manually in commercial farming and it is used in the manufacture of ropes and baskets or as reinforcement in composite with organic matrix of components for cars, buses and trucks. On the other hand, the extrusion process can produce composites with high-density matrix with fibers, low permeability and good interface between fiber and matrix. This process is also compatible with the use of vegetable fibers as raw materials in the production of cost-effective construction elements such as ceiling panels and drywalls. The objective of this research was use the analysis of variance (ANOVA) for evaluating the content and length of curauá fibers on the mechanical behavior of the extruded cementitious composites. Composites without fibers and reinforced with 1% and 2% by mass of fibers as well as 6 mm and 10 mm of length these curauá fibers were evaluated. The composites with fibers of 10 mm have showed better mechanical results. Besides, the composites with fibers curauá after 200 accelerated aging cycles were better than one non-aging.

Potential of Using Amazon Natural Fibers to Reinforce Cementitious Composites: A Review

“…Generally speaking, NLFs can be fibrillar or tubular [ 70 , 71 ]. Tubular fibers are molded inside and have a high adhesion to the matrix, superior to fibrillar fibers, which are massive, presenting less adhesion to the matrix and, consequently, lower mechanical resistance [ 71 ].…”

Evaluation of the behavior of mortars produced with fibers from the straw of carnauba: effects of the content of addition and length used

“…As for the overlapping effects, it should be noted, above all, that the higher CSF content increases the amount of voids in the mixture and this makes the mortars less compact and, therefore, less resistant. This behavior could probably be due to the superposition of some phenomena: (i) poor distribution of fibers within the matrix [23,40,41], which gives less load bearing capacity; (ii) durability of the fiber within the matrix due to the attack of calcium hydroxide [17,23,41], resulting in loss of mechanical strength; (iii) the hydrophilic nature of the fibers of plant origin and, consequently, the greater absorption of water [17] explain the obtaining of less compact mixtures, as previously discussed. This characteristic also causes the fibers to undergo dimensional variation due to the water loss process during hydration of the cementitious matrix [42].…”

“…The incorporation of CSF regardless of the content and length incorporated resulted in mortars with less resistance to bending, as shown in Figure 5. Bearing in mind that this mechanical property is influenced by the porosity of the matrix [41], it can be inferred that a higher fiber content contributes to obtain less compact mixtures due to the fiber dispersion deficiency in the cementitious matrix. As a result, mortars with lower flexural strength are obtained.…”

“…As a result, mortars with lower flexural strength are obtained. Flexural strength (MPa) In a recent study, TEIXEIRA et al [41] observed that the inclusion of curauá fibers, while increasing the toughness and reinforcement of composites, the transfer of tension between the fibers and the matrix is deficient. This may explain the decrease in the flexural strength of mortars with the incorporation of CSF.…”

Síntese de termorrígidos fenólicos simultaneamente à formação de compósitos: fibras e mantas como reforço vegetal

“…Fonte: (a) GUTIÉRREZ et al (2014) (b) https://www.engenhariacivil.com/estruturas-betao-compositos-reforcados-fibras-carbono (c) http://www.aviacao.org/article/materiais-compositos/12/ (d) http://www.aviacao.org/article/materiais-compositos/ (e) https://www.engenhariacivil.com/estruturas-betao-compositos-reforcados-fibras-carbono Quanto ao tipo de fibra a ser utilizada como reforço em compósitos, estas podem ser de natureza sintética como: fibra de vidro (CALABRESE et al, 2019), carbono (KERN et al, 2019), basalto (SERGI et al, 2019), e/ou vegetais como: bagaço de cana-de-açúcar (GUNA et al, 2019), sisal (DE OLIVEIRA et al, 2017), curauá (TEIXEIRA et al, 2019), dentre outras, tanto na forma de fibras curtas como longas. Como as fibras naturais são nosso objeto de estudo, estas serão destacadas ao longo do texto.…”