Free, restrained and drying shrinkage of cement mortar composites reinforced with vegetable fibres

Filho, Romildo Dias Toledo; Ghavami, Khosrow; Sanjuán, Miguel Ángel; England, G. L.

doi:10.1016/j.cemconcomp.2004.09.005

Cited by 245 publications

(82 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…3) and contributes to a higher drying shrinkage. This is due to more moisture paths being created into the matrix, which is also reported by Toledo Filho et al [42] in their study of the effect of vegetable fibres on drying shrinkage of cement mortar composites.…”

Section: Thermal Propertiessupporting

confidence: 58%

Mechanical properties of cotton fabric reinforced geopolymer composites at 200–1000 °C

et al. 2014

View full text Add to dashboard Cite

Abstract:Geopolymer composites containing woven cotton fabric (0-8.3 wt%) were fabricated using the hand lay-up technique, and were exposed to elevated temperatures of 200 ℃, 400 ℃, 600 ℃, 800 ℃ and 1000 ℃. With an increase in temperature, the geopolymer composites exhibited a reduction in compressive strength, flexural strength and fracture toughness. When heated above 600 ℃, the composites exhibited a significant reduction in mechanical properties. They also exhibited brittle behavior due to severe degradation of cotton fibres and the creation of additional porosity in the composites. Microstructural images verified the existence of voids and small channels in the composites due to fibre degradation.

show abstract

Section: Thermal Propertiessupporting

confidence: 58%

Mechanical properties of cotton fabric reinforced geopolymer composites at 200–1000 °C

et al. 2014

View full text Add to dashboard Cite

show abstract

“…The elongation at break decreased from 63.9 ± 28.9% (treated, 10 mm) to 21.6 ± 10.1% (untreated, 50 mm). The elongation of the plasma treated fibres for 10 mm fibres was higher than the interval 14 to 41% stated by Toledo Filho et al (2005). However, it is in accordance with the conclusions of Ramakrishna and Sundararajan (2005), who state up to 75% and the tensile strength of 15 to 327 MPa.…”

Section: Resultssupporting

confidence: 69%

“…11); the maximum measured value was 185 MPa. These values are in accordance with the intervals stated by Toledo Filho et al (2005) of 108 to 252 MPa (fibre diameter of 0.11 to 0.53 mm) or Munawar et al (2007) with values of 137 ± 11 MPa (fibre diameter of 0.120 ± 0.005 mm). The elongation at break decreased from 63.9 ± 28.9% (treated, 10 mm) to 21.6 ± 10.1% (untreated, 50 mm).…”

Section: Resultssupporting

confidence: 68%

Influence of Plasma Treatment on Mechanical Properties of Cellulose-based Fibres and Their Interfacial Interaction in Composite Systems

2017

View full text Add to dashboard Cite

The use of natural reinforcements is growing in current material engineering due to their satisfactory mechanical properties such as availability, price, and environmental aspects. Synthetic fibres are more often replaced by natural ones in many applications. The interfacial interactions of matrices are key factors that limit the use of natural fibres. The matrix interactions of natural fibres can be optimized by surface treatments, such as plasma treatment. This paper examined the possibility of using plasma to treat natural fibres. The basic mechanical characteristics of the fibres were changed by this treatment. Changes in the surface structures and the subsequent interaction with polymeric matrices with epoxy resins were evaluated by scanning electron microscopy. The plasma treatments of fibres did not decrease the tensile strength but did optimize their surface structures.

show abstract

“…Para garantir a boa dispersão do material, fibras de sisal com mais de 50 mm de comprimento não são usualmente utilizadas como reforço de argamassas e concretos (Guimarães, 1987;Swift & Smith, 1979) razão por que nesses compósitos a ruptura é caracterizada pela propagação instável da fissura com arrancamento gradual das fibras de dentro da matriz, o que acarreta um ganho na capacidade de absorver energia do material. Desta forma, a inclusão de fibras curtas de sisal em argamassas de cimento não tem influência benéfica sobre o aumento da resistência a tração ou compressão mas proporciona a melhoria de propriedades, tais como tenacidade na compressão (Toledo Filho et al, 1999;Lima, 2004), resistência e tenacidade a flexão (Toledo Filho et al, 2003) e controle da fissuração por retração por secagem (Toledo Filho et al, 2005).…”

Section: Introductionunclassified

Efeito da argila calcinada sobre a durabilidade de argamassas reforçadas com fibras curtas de sisal

Filho¹,

Filho

Lima³

2010

Rev. bras. eng. agríc. ambient.

Self Cite

View full text Add to dashboard Cite

RESUMOO interesse pelo uso de fibras vegetais como reforço de matrizes, à base de cimento, tem crescido em todo o mundo nos últimos anos, sendo limitado pela baixa durabilidade das fibras no meio alcalino. Com o tempo, as fibras podem mineralizar devido à migração de hidróxido de cálcio (CH) da matriz para o lúmen e paredes das fibro-células. Procurou-se consumir, no presente estudo, o CH livre utilizando-se resíduo de tijolo moído e metacaulinita em substituição parcial, de 20 e 40% em peso, do cimento portland. Compósitos com fibras de sisal e matrizes cimento-pozolana foram submetidos a ensaios de resistência a flexão, após 28 dias de cura em água, 135 e 180 dias de envelhecimento natural e após 94 ciclos de molhagem e secagem. Os resultados indicaram que é possível consumir todo o CH da matriz, o que resultou na manutenção da tenacidade inicial do compósito e no aumento da sua resistência a flexão após exposição natural ou ciclos de molhagem e secagem.Palavras-chave: fibra de sisal, compósitos, resíduo cerâmico, flexão, envelhecimento acelerado Effect of calcined clay on aging of sisal short fiber reinforced mortar ABSTRACTIn the last few years a growing interest in the use of sisal fibers as reinforcement in cement based composites has been observed. However, the main concern for its use is related with the durability of the fibers in the alkaline water of concrete as they can mineralize due to the migration of calcium hydroxide to the fiber lumen and cell walls. In this study, the alkalinity of the matrix was reduced using metakaolin and crushed waste calcined clay bricks as cement replacement. The percentage of cement replacement ranged from 20 to 40% on weight basis. Flexural tests were carried out in the composites after 28 days of cure in water, 135 and 180 days of ageing in the open air and after 94 cycles of wetting and drying. These results indicated that the mixture with cement replacement consumed all calcium hydroxide and kept the toughness over time.

show abstract

Free, restrained and drying shrinkage of cement mortar composites reinforced with vegetable fibres

Cited by 245 publications

References 15 publications

Mechanical properties of cotton fabric reinforced geopolymer composites at 200–1000 °C

Mechanical properties of cotton fabric reinforced geopolymer composites at 200–1000 °C

Influence of Plasma Treatment on Mechanical Properties of Cellulose-based Fibres and Their Interfacial Interaction in Composite Systems

Efeito da argila calcinada sobre a durabilidade de argamassas reforçadas com fibras curtas de sisal

Contact Info

Product

Resources

About