scholarly journals Mechanical properties and sustainability aspects of coconut fiber modified concrete

2021 ◽  
Vol 26 (1) ◽  
pp. 64-71
Author(s):  
Harveth Gil ◽  
Alejandro Alberto Zuleta ◽  
David Esteban Reyes
Keyword(s):  
Mechanical Properties ◽  
Plain Concrete ◽  
Embodied Energy ◽  
Coir Fiber ◽  
Audit Tool ◽  
Coconut Fiber ◽  
Cracking Behavior ◽  
Vegetable Fibers ◽  
Coir Fibers ◽  
Concrete Mechanical Properties

Coir fiber has been examined for their suitability as reinforcement of concrete. Mechanical properties and sustainability aspects of concrete composites were estimated after 7. 14, and 28 days of curing. Natural reinforcement of 0.46 and 0.62% by weight of coir fiber was added. Fibers were analyzed by means of scanning electron microscope (SEM). Besides, an Eco-audit tool has been used to estimate energy and carbon emission of material, manufacturing, transportation, and disposal phases. It was found that fibers additions lowered the compressive strength compared to plain concrete. However, failures of the composites exhibited good post-cracking behavior. The use of vegetable fibers affects positively the life cycle of the material. Eco-audit results indicate that there is a potential to reduce between 9.15% and 13.35% of embodied energy and between 9.61% and 13.94% of CO2 during the material production phase. These suggest that coir fibers could be useful from the environmental view, although more studies regarding their durability are needed.

scholarly journals Coir Fibers Treated with Henna as a Potential Reinforcing Filler in the Synthesis of Polyurethane Composites

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1128
Author(s):  
Sylwia Członka ◽  
Anna Strąkowska ◽  
Agnė Kairytė
Keyword(s):  
Mechanical Properties ◽  
High Energy ◽  
Dynamic Mechanical Properties ◽  
Milling Process ◽  
Coir Fiber ◽  
Lawsonia Inermis ◽  
Coir Fibers ◽  
Mechanical Performances ◽  
The Impact ◽  
Reinforcing Filler

In this study, coir fibers were successfully modified with henna (derived from the Lawsonia inermis plant) using a high-energy ball-milling process. In the next step, such developed filler was used as a reinforcing filler in the production of rigid polyurethane (PUR) foams. The impact of 1, 2, and 5 wt % of coir-fiber filler on structural and physico-mechanical properties was evaluated. Among all modified series of PUR composites, the greatest improvement in physico-mechanical performances was observed for PUR composites reinforced with 1 wt % of the coir-fiber filler. For example, on the addition of 1 wt % of coir-fiber filler, the compression strength was improved by 23%, while the flexural strength increased by 9%. Similar dependence was observed in the case of dynamic-mechanical properties—on the addition of 1 wt % of the filler, the value of glass transition temperature increased from 149 °C to 178 °C, while the value of storage modulus increased by ~80%. It was found that PUR composites reinforced with coir-fiber filler were characterized by better mechanical performances after the UV-aging.

Characterization and Utilization of Coconut Fibers of the Caribbean

2014 ◽  
Vol 1611 ◽  
pp. 95-104 ◽  
Author(s):  
Nadira Mathura ◽  
Duncan Cree ◽  
Ryan P. Mulligan
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Electron Micrographs ◽  
Saline Water ◽  
Gauge Length ◽  
Scanning Electron Micrographs ◽  
Coir Fiber ◽  
Coir Fibers ◽  
The Caribbean ◽  
Scanning Electron

ABSTRACTIn many tropical countries coconut (coir) fiber production is a major source of income for rural communities. The Caribbean has an abundance of coconuts but research into utilizing its by-products is limited. Environmentally friendly coir fibers are natural polymers generally discarded as waste material in this region. Research has shown that coir fiber from other parts of the world has successfully been recycled. This paper therefore investigates the mechanical properties of Caribbean coir fiber for potential applications in civil engineering.Approximately four hundred fibers were randomly taken from a coir fiber stack and subjected to retting in both distilled and saline water media. The mechanical properties of both the retted and unretted coir fibers were evaluated at weekly increments for a period of 3 months. Tensile strength test, x-ray diffraction analysis and scanning electron micrographs were used to assess trends and relationships between fiber gauge lengths, diameter, tensile strength and Young’s modulus. Diameters ranged between 0.11 mm-0.46 mm, while fiber samples were no longer than 250 mm in length. The tensile strength and strain at break decreased as the gauge length increased for both unretted and retted fibers. The opposite occurred for the relationship between the gauge length and Young’s modulus. Additionally, the tensile strength and modulus decreased as the fiber diameter increased. Neither distilled nor saline water improved the coir fiber’s crystalline index. Scanning electron micrographs qualitatively assessed fiber surfaces and captured necking and microfibril degradation at the fractured ends.The analysis revealed that the tensile strength, modulus, strain at break and crystallinity properties of the Caribbean coir fibers were comparable to commercially available coir fiber which are currently being used in many building applications.

scholarly journals The Development of Coir- Concrete Blocks Aslightweight Construction Material

2020 ◽  
Vol 9 (3) ◽  
pp. 924-927
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Construction Material ◽  
Mechanical Tests ◽  
Absorption Characteristic ◽  
Coir Fiber ◽  
Lightweight Construction ◽  
Coir Fibers ◽  
Concrete Blocks ◽  
Average Compressive Strength

This paper presents the research into the incorporation of coir fiber in concrete blocks for construction purposes. Mechanical tests were performed on concrete samples containing different percentages of chopped coir fibers (0.25, 0.50, 0.75 and 1 by weight of aggregates). Density and water absorption characteristic of the samples were also measured and evaluated in relation to the mechanical properties. It was found that the average compressive strength of the blocks is in the range of 5–6 MPa and the average flexural strength is in the range of 1.04–1.47 MPa, which are lower compared to the results of samples without coir. Nevertheless, the compressive strength range of coir- concrete blocks in this study satisfies the requirements of relevant standards (SNI, AS and ASTM), specifically for non-structural or non-load-bearing concrete blocks. Furthermore, the density of the coir-concrete blocks is between 1230–1536 kg/m3 which fit into the category of lightweight blocks. Based on the results, it can therefore be suggested that the development of coir-concrete blocks is feasible for non-structural, non-loadbearing, lightweight construction material.

scholarly journals Determination and Review of Physical and Mechanical Properties of Raw and Treated Coconut Fibers for Their Recycling in Construction Materials

Fibers ◽  
2020 ◽  
Vol 8 (6) ◽  
pp. 37
Author(s):  
Huyen Bui ◽  
Nassim Sebaibi ◽  
Mohamed Boutouil ◽  
Daniel Levacher
Keyword(s):  
Mechanical Properties ◽  
Laboratory Tests ◽  
Natural Fibers ◽  
Construction Materials ◽  
Physical And Mechanical Properties ◽  
Coconut Fiber ◽  
Vegetable Fibers ◽  
Durability Properties ◽  
The Past ◽  
Coconut Fibers

In order to reduce the dependency on conventional materials and negative environmental impacts, one of the main responsibilities of the construction field is to find new eco-friendly resources to replace the traditional materials partially. Natural fibers were known as potential candidates for the reinforcement of structures in civil engineering by virtue of their advantages. Among the different kinds of vegetable fibers, coconut fiber has been exploited in a limited way over the past few years. This paper aims at evaluating the different properties of local coconut fibers (Vietnam). Several laboratory tests provide geometrical, physical, mechanical properties and durability properties that are compared with literature results obtained from similar natural fibers. The local coconut fibers tested demonstrated properties suitable for reinforced mortars. With adequate control of their preparation, they could be reused in the manufacture of mortars in the construction.

Comparative Analysis on the Elastic Behavior of Composite Materials Based on Plant Fibers: Bamboo / Epoxy and Coconut / Epoxy

2020 ◽  
Vol 12 (2) ◽  
pp. 127-135
Author(s):  
Allel Mokaddem ◽  
Bendouma Doumi ◽  
Mohammed Belkheir ◽  
Amina Touimi
Keyword(s):  
Mechanical Properties ◽  
Comparative Analysis ◽  
Composite Materials ◽  
Experimental Tests ◽  
Elastic Behavior ◽  
Coconut Fiber ◽  
Plant Fibers ◽  
Shear Damage ◽  
Vegetable Fibers ◽  
Genetic Simulation

Background: The exploitation by the industries of vegetable fibers in the field of composite materials has made it possible to reduce the dependency of oil which is the result of their mechanical properties, their thermal resistance and biodegradability. Methods: In this work, we carried out a comparative study by a genetic simulation on two materials based on different natural reinforcements (Bamboo and Coconut) to see the influence of its fibers on the elastic behavior of bio-composite materials. Results: The results of our genetic simulation showed that Bamboo / Epoxy is more resistant than Coconut / Epoxy and that shear damage of Bamboo / Epoxy is lower than that of Coconut / Epoxy by 11 to 12.5%. Conclusion: The results are similar to the results given by Rao KMM where he showed by experimental tests that Bamboo fiber is the most resistant when compared with other fibers especially coconut fiber.

scholarly journals Effect of the Notch-to-Depth Ratio on the Post-Cracking Behavior of Steel-Fiber-Reinforced Concrete

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 445
Author(s):  
José Valdez Aguilar ◽  
César A. Juárez-Alvarado ◽  
José M. Mendoza-Rangel ◽  
Bernardo T. Terán-Torres
Keyword(s):  
Reinforced Concrete ◽  
Plain Concrete ◽  
Fiber Reinforced Concrete ◽  
Fiber Reinforced ◽  
Steel Fiber Reinforced Concrete ◽  
Cracking Behavior ◽  
Bending Tests ◽  
Depth Ratio ◽  
Residual Performance ◽  
Concrete Control

Concrete barely possesses tensile strength, and it is susceptible to cracking, which leads to a reduction of its service life. Consequently, it is significant to find a complementary material that helps alleviate these drawbacks. The aim of this research was to determine analytically and experimentally the effect of the addition of the steel fibers on the performance of the post-cracking stage on fiber-reinforced concrete, by studying four notch-to-depth ratios of 0, 0.08, 0.16, and 0.33. This was evaluated through 72 bending tests, using plain concrete (control) and fiber-reinforced concrete with volume fibers of 0.25% and 0.50%. Results showed that the specimens with a notch-to-depth ratio up to 0.33 are capable of attaining a hardening behavior. The study concludes that the increase in the dosage leads to an improvement in the residual performance, even though an increase in the notch-to-depth ratio has also occurred.

scholarly journals Influence of Alkali Treatment on the Microstructure and Mechanical Properties of Coir and Abaca Fibers

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2636
Author(s):  
Petr Valášek ◽  
Miroslav Müller ◽  
Vladimír Šleger ◽  
Viktor Kolář ◽  
Monika Hromasová ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Composite Materials ◽  
Alkali Treatment ◽  
Fiber Surface ◽  
Cellulose Fibers ◽  
Sem Analysis ◽  
Experimental Program ◽  
Time Interval ◽  
The European Union ◽  
Vegetable Fibers

Composite materials with natural fillers have been increasingly used as an alternative to synthetically produced materials. This trend is visible from a representation of polymeric composites with natural cellulose fibers in the automotive industry of the European Union. This trend is entirely logical, owing to a preference for renewable resources. The experimental program itself follows pronounced hypotheses and focuses on a description of the mechanical properties of untreated and alkali-treated natural vegetable fibers, coconut and abaca fibers. These fibers have great potential for use in composite materials. The results and discussion sections contribute to an introduction of an individual methodology for mechanical property assessment of cellulose fibers, and allows for a clear definition of an optimal process of alkalization dependent on the content of hemicellulose and lignin in vegetable fibers. The aim of this research was to investigate the influence of alkali treatment on the surface microstructure and tensile properties of coir and abaca fibers. These fibers were immersed into a 5% solution of NaOH at laboratory temperature for a time interval of 30 min, 1 h, 2 h, 3 h, 6 h, 12 h, 24 h, and 48 h, rinsed and dried. The fiber surface microstructures before and after the alkali treatment were evaluated by SEM (scanning electron microscopy). SEM analysis showed that the alkali treatment in the NaOH solution led to a gradual connective material removal from the fiber surface. The effect of the alkali is evident from the visible changes on the surface of the fibers.

Synthesis and evaluation of mechanical properties for coconut fiber composites-A review

2021 ◽  
Author(s):  
Nutenki Shravan Kumar ◽  
Tanya Buddi ◽  
A. Anitha Lakshmi ◽  
K.V. Durga Rajesh
Keyword(s):  
Mechanical Properties ◽  
Fiber Composites ◽  
Coconut Fiber
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