Effect of Natural and Polypropylene Fibers on early Age Cracking of Mortars

2022 ◽  
Author(s):  
Mahmoud Saad ◽  
Vincent Sabathier ◽  
Anaclet Turatsinze ◽  
Sandrine Geoffroy
Keyword(s):  
Crack Width ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Fiber Reinforcement ◽  
Image Correlation ◽  
Polypropylene Fibers ◽  
Great Ability ◽  
Hemp Fibers ◽  
Plastic Shrinkage ◽  
Maximum Crack

Throughout time, the use of lignocellulosic resources has been implemented in the development of building materials. Among these resources, natural fibers are used as mineral binders reinforcement due to their specific mechanical properties. This experimental investigation focused on effect of flax and hemp fiber reinforcement on the resistance of pozzolanic-based mortars to cracking due to restrained plastic shrinkage. Results were compared with polypropylene fiber reinforcement and with control mortar without fibers. The quantity of fibers added to the mortar mix were respectively 0.25% - 0.5% by mass of binder for polypropylene fibers and 0.5% - 1% by mass of binder for flax and hemp fibers. All fibers have a similar length of 12 mm. The cracking sensitivity was evaluated based on two different methods: the first consists in casting the mortar in a metal mold with stress risers whose criteria are inspired by the ASTM standards. The second consists in pouring the mortar on a brick support. In order to assess the effect of fibers on cracking due to restrained plastic shrinkage, the number of cracks, total crack area and maximum crack width within the first 6 hours after casting were determined using digital image correlation (DIC). Results showed that the flax and hemp fibers were more effective in controlling restrained plastic shrinkage cracking compared to polypropylene fibers. With a natural fiber of 1% by mass of binder, maximum crack width was reduced by at least 70% relative to control mortar based specimens. Natural fibers show great ability to propensity for cracking due to restrained plastic shrinkage; so that, they could be an alternative and ecological solution for polypropylene fibers.

Effect of Alkali and Silane Treatment on the Thermal Stability of Hemp Fibers as Reinforcement in Composite Structures

2011 ◽  
Vol 415-417 ◽  
pp. 666-670 ◽  
Author(s):  
Na Lu ◽  
Shubhashini Oza ◽  
Ian Ferguson
Keyword(s):  
Thermal Stability ◽  
Composite Structures ◽  
Natural Fiber ◽  
Alkali Treatment ◽  
Thermo Gravimetric Analysis ◽  
Natural Fibers ◽  
Gravimetric Analysis ◽  
Silane Treatment ◽  
Hemp Fibers ◽  
Thermal Stability Of

Natural fiber reinforced composites are being used as reinforcement material in composite system due to their positive environmental benefits. Added to that, natural fibers offer advantages such as low density, low cost, good toughness, high specific strength, relatively non-abrasive and wide availability. However, the low thermal stability of natural fibers is one of the major challenges to increase their use as reinforcing component. In this study, a thorough investigation has been done to compare the effect of two chemical treatment methods on the thermal stability of hemp fibers. 5wt% sodium hydroxide and 5wt% triethoxyvinylsilane was used for the treatment of hemp fibers. Fourier transform infrared spectroscopy, scanning electron microscopy and thermo gravimetric analysis were used for characterization of untreated and treated fiber. The results indicated that 24 hours alkali treatment and 3 hours silane treatment time enhanced the thermal stability of the hemp fiber. However, alkali treatment shows better improvement compared to silane treatment.

Valorization of Vegetal Fibers in Anti-Fissuration Screed Mortar Formulation

2022 ◽  
Author(s):  
Sergio Pons Ribera ◽  
Rabah Hamzaoui ◽  
Johan Colin ◽  
Benitha Vasseur ◽  
Laetitia Bessette ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Strength ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Point Of View ◽  
Synthetic Fiber ◽  
Sem Images ◽  
Hemp Fibers ◽  
Synthetic Fibers ◽  
Rigid Fibers

This work, which is part of the FIBRABETON project, aims to anti-fissuration screed formulations proposition based on natural fibers and comparing these formulations to a synthetic fiber-screed formulation. Different natural fiber (hemp, flax, miscanthus and bamboo) with contents rangingfrom 0.4% to 0.8% were tested. The spread (slump), the shrinkage and mechanical strength (flexural and compressive) studies were carried out. SEM images of natural fibers and natural fibers screed formulation were analyzed. Overall, it is found that all natural fibers screed formulations tested, have shown better behaviour than the synthetic fibers screed formulation in point of view workability, shrinkage and mechanical properties. The lowest shrinkage value is found in the case of the H5 (5 mm long hemp fibers) screed formulation. Generally speaking, the mechanical strength values (flexural and compressive) are more or less similar between natural soft fibers (hemp and flax) and rigid fibers (miscanthus and bamboo). Taking in account slump, shrinkage and mechanical behavior, the proposed good compromise in this work is the H5 screed formulation.

scholarly journals Study on the Preparation and Fracture Behavior of Red Mud-Yellow Phosphorus Slag-Based Concrete

2019 ◽  
Vol 2019 ◽  
pp. 1-15
Author(s):  
Xianhai Li ◽  
Qin Zhang ◽  
Song Mao ◽  
Longjiang Li ◽  
Jingbo Wang
Keyword(s):  
Red Mud ◽  
Crack Width ◽  
Fracture Behavior ◽  
Vertical Direction ◽  
Image Correlation ◽  
Cement Concrete ◽  
Slag Cement ◽  
Yellow Phosphorus ◽  
Maximum Crack ◽  
Phosphorous Slag

Serious environmental pollution issues caused by the storage and exposure of large amounts of red mud (RM) and yellow phosphorus slag (YPS) have raised significant concerns. Red mud-yellow phosphorous slag-cement concrete (RM-YPS-CC) is prepared with 25% yellow phosphorus slag content (YPSC) and 10% red mud content (RMC) to replace a portion of the cement at the age of 28 days and was found in this study to satisfy the mechanical property requirements. More ettringite and portlandite were generated with the RM-YPS-CC than with the yellow phosphorous slag-cement concrete (YPS-CC). In addition, the cementitious materials were more interlaced, and there was more disorder in the crystals of the RM-YPS-CC, which formed a more complex spatial structure than the YPS-CC did. Without RM, the initial cracking strength on the surface of the concrete was 5–6 MPa, the maximum crack width was 3.96 mm, and the crack number was 8. However, the cracking strength was 26.5–27 MPa with RMC5, the maximum crack width was 0.66 mm with RMC15, and the crack number was 3 with RMC15. Moreover, studies using the digital image correlation (DIC) method indicated that the displacement distribution and evolution of the first crack area changed quickly at 10 MPa in either horizontal or vertical direction, and a similar trend was maintained from 10 MPa to 27.1 MPa for the YPS-CC. However, with a small distribution and evolution of horizontal or vertical displacement from 5 MPa to 25 MPa, the evolution would change rapidly when reaching 30 MPa for RM-YPS-CC. This study aims to provide new insights into the wide application of YPS and RM for saving energy and reducing emissions and to develop a new method to study the fracture behavior of concrete.

Interfacial Modification of Hemp Fiber Reinforced Composites Using Fungal and Alkali Treatment

2007 ◽  
Vol 1 (1) ◽  
pp. 109-117 ◽  
Author(s):  
K. L. Pickering ◽  
Y. Li ◽  
R. L. Farrell ◽  
M. Lay
Keyword(s):  
Natural Fiber ◽  
Fiber Composite ◽  
Alkali Treatment ◽  
Natural Fibers ◽  
Fiber Reinforced ◽  
Hemp Fiber ◽  
Hemp Fibers ◽  
Polypropylene Composites ◽  
Interfacial Modification ◽  
Industrial Hemp

Increasing worldwide environmental awareness is encouraging scientific research into developing cheaper, more sustainable materials. Industrial hemp fiber is one of the strongest and stiffest available natural fibers [K. L. Pickering, M. Priest, T. Watts, G. Beckermann, and S. N. Alam, J. Adv. Mater. 37, 15 (2005)] and therefore has great potential in composite materials. Incorporated into a thermoplastic matrix, it gives a structural material that is cheap, lightweight, and recyclable. However, natural fibers are commonly incompatible with common molding thermoplastics such as polypropylene, which limits the performance of the composites produced. The main objective of the current work was to investigate the use of fungi to treat hemp fiber to create better bonding characteristics in natural fiber reinforced polypropylene composites. X-ray diffraction (XRD), ζ-potential, lignin testing, thermal analysis, and scanning electron microscopy (SEM) were used to characterize the effect of treatment on hemp fibers. A combined alkali and fungi treated fiber composite produced the highest tensile strength of 48.3 MPa, an increase of 32% compared to composites with untreated fiber.

Effects of Natural Fiber Reinforcement on Water Absorption of Compressed Stabilized Earth Blocks

2012 ◽  
Vol 2 (11) ◽  
pp. 165-167
Author(s):  
B.O .Ugwuishiwu B.O .Ugwuishiwu ◽  
◽  
B.O. Mama B.O. Mama ◽  
N. M Okoye N. M Okoye
Keyword(s):  
Water Absorption ◽  
Natural Fiber ◽  
Fiber Reinforcement ◽  
Earth Blocks

Information in United States Patents on works related to ‘Natural Fibers’: 2000-2018

2019 ◽  
Vol 12 (1) ◽  
pp. 4-76 ◽  
Author(s):  
Krittirash Yorseng ◽  
Mavinkere R. Sanjay ◽  
Jiratti Tengsuthiwat ◽  
Harikrishnan Pulikkalparambil ◽  
Jyotishkumar Parameswaranpillai ◽  
...  
Keyword(s):  
United States ◽  
Composite Materials ◽  
Natural Fiber ◽  
Comprehensive Evaluation ◽  
Natural Fibers ◽  
Fiber Reinforced Composites ◽  
Reinforced Composites ◽  
Fiber Reinforced ◽  
Macro Scale ◽  
Structural Applications

Background: This era has seen outstanding achievements in materials science through the advances in natural fiber-based composites. The new environmentally friendly and sustainability concerns have imposed the chemists, biologists, researchers, engineers, and scientists to discover the engineering and structural applications of natural fiber reinforced composites. Objective: To present a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials. Methods: The patent data have been taken from the external links of US patents such as IFI CLAIMS Patent Services, USPTO, USPTO Assignment, Espacenet, Global Dossier, and Discuss. Results: The present world scenario demands the usage of natural fibers from agricultural and forest byproducts as a reinforcement material for fiber reinforced composites. Natural fibers can be easily extracted from plants and animals. Recently natural fiber in nanoscale is preferred over micro and macro scale fibers due to its superior thermo-mechanical properties. However, the choice of macro, micro, and nanofibers depends on their applications. Conclusion: This document presents a comprehensive evaluation of information from 2000 to 2018 in United States patents in the field of natural fibers and their composite materials.

scholarly journals Characterization of a new natural fiber extracted from Corypha taliera fruit

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Taslima Ahmed Tamanna ◽  
Shah Alimuzzaman Belal ◽  
Mohammad Abul Hasan Shibly ◽  
Ayub Nabi Khan
Keyword(s):  
Tensile Strength ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Morphological Characteristics ◽  
Synthetic Fiber ◽  
X Ray Diffraction ◽  
Reinforced Composite ◽  
Potential Alternative

AbstractThis study deals with the determination of new natural fibers extracted from the Corypha taliera fruit (CTF) and its characteristics were reported for the potential alternative of harmful synthetic fiber. The physical, chemical, mechanical, thermal, and morphological characteristics were investigated for CTF fibers. X-ray diffraction and chemical composition characterization ensured a higher amount of cellulose (55.1 wt%) content and crystallinity (62.5%) in the CTF fiber. The FTIR analysis ensured the different functional groups of cellulose, hemicellulose, and lignin present in the fiber. The Scherrer’s equation was used to determine crystallite size 1.45 nm. The mean diameter, specific density, and linear density of the CTF fiber were found (average) 131 μm, 0.86 g/cc, and 43 Tex, respectively. The maximum tensile strength was obtained 53.55 MPa for GL 20 mm and Young’s modulus 572.21 MPa for GL 30 mm. The required energy at break was recorded during the tensile strength experiment from the tensile strength tester and the average values for GL 20 mm and GL 30 mm are 0.05381 J and 0.08968 J, respectively. The thermal analysis ensured the thermal sustainability of CTF fiber up to 230 °C. Entirely the aforementioned outcomes ensured that the new CTF fiber is the expected reinforcement to the fiber-reinforced composite materials.

scholarly journals The Structure and Mechanical Properties of Hemp Fibers-Reinforced Poly(ε-Caprolactone) Composites Modified by Electron Beam Irradiation

2021 ◽  
Vol 11 (12) ◽  
pp. 5317
Author(s):  
Rafał Malinowski ◽  
Aneta Raszkowska-Kaczor ◽  
Krzysztof Moraczewski ◽  
Wojciech Głuszewski ◽  
Volodymyr Krasinskyi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Electron Beam ◽  
Impact Strength ◽  
Flexural Modulus ◽  
Natural Fibers ◽  
High Energy ◽  
Electron Radiation ◽  
Elongation At Break ◽  
Hemp Fibers

The need for the development of new biodegradable materials and modification of the properties the current ones possess has essentially increased in recent years. The aim of this study was the comparison of changes occurring in poly(ε-caprolactone) (PCL) due to its modification by high-energy electron beam derived from a linear electron accelerator, as well as the addition of natural fibers in the form of cut hemp fibers. Changes to the fibers structure in the obtained composites and the geometrical surface structure of sample fractures with the use of scanning electron microscopy were investigated. Moreover, the mechanical properties were examined, including tensile strength, elongation at break, flexural modulus and impact strength of the modified PCL. It was found that PCL, modified with hemp fibers and/or electron radiation, exhibited enhanced flexural modulus but the elongation at break and impact strength decreased. Depending on the electron radiation dose and the hemp fibers content, tensile strength decreased or increased. It was also found that hemp fibers caused greater changes to the mechanical properties of PCL than electron radiation. The prepared composites exhibited uniform distribution of the dispersed phase in the polymer matrix and adequate adhesion at the interface between the two components.

scholarly journals Valorization of Invasive Plants from Macaronesia as Filler Materials in the Production of Natural Fiber Composites by Rotational Molding

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2220
Author(s):  
Zaida Ortega ◽  
Francisco Romero ◽  
Rubén Paz ◽  
Luis Suárez ◽  
Antonio Nizardo Benítez ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Invasive Plant ◽  
Natural Fiber ◽  
Ricinus Communis ◽  
Local Level ◽  
Natural Fibers ◽  
Fiber Composites ◽  
Filler Materials ◽  
Natural Fiber Composites ◽  
Rotational Molding

This paper compares the mechanical properties of different natural fiber composites produced by rotational molding as a way of waste valorization from campaigns to control invasive plant species in Macaronesia. Rotomolded parts produced with polymeric matrices (polyethylene) and filled with up to 20% by weight of cellulosic fibers obtained from Arundo donax L., Pennisetum setaceum, and Ricinus communis plants were characterized in terms of tensile, flexural, and impact strength. It was found that the sieving of natural fibers allowed for their introduction in higher loadings, from 10 (for un-sieved material) to 20%; fiber size greatly affected the mechanical properties of the final parts, although some combinations were proven not to reduce the mechanical properties of the neat resin. This study is a first approach to the valorization of residues obtained from periodic campaigns of the control of invasive species performed by public authorities, usually at the local level. It is important to highlight that the main objective of this research did not focus on economically profitable activity; instead, it was focused on the reduction of wastes to be disposed from ecosystem maintenance actions and the investment of potential income into preservation policies.

Study on Thermal, Thermo-Mechanical, and Flexural Properties of Jute Fiber Surface Modification and Its Reinforced Composite

2021 ◽  
Vol 8 (5) ◽  
pp. 11-17
Author(s):  
Syed Rashedul Islam ◽  
Abeer Alassod ◽  
Mohammed Kayes Patoary ◽  
Tayyab Naveed ◽  
Md Arshad Ali ◽  
...  
Keyword(s):  
Natural Fiber ◽  
Natural Fibers ◽  
Fiber Surface ◽  
Jute Fiber ◽  
Flexural Properties ◽  
Reinforced Composites ◽  
Acid Pretreatment ◽  
Chemical Treatments ◽  
Jute Fibers ◽  
Composite Properties

In recent years, reinforced composites from biodegradable and natural fibers have a worldwide scope for advanced applications. However, the core limitation of natural fiber reinforced composites are poor consistency among supporting fibers and the matrix. Therefore, optimal structural performance of fibers and matrix is desirable. In this study, chemical treatments (i.e., alkali pretreatment, acid pretreatment, and scouring) were applied to jute fibers for improvement of composite properties. Thermal, thermo-mechanical, and flexural properties, and surface morphology, of untreated and treated jute fibers were studied on the treated fibers. Jute fiber/epoxy composite properties were analyzed by thermogravimetric analysis (TGA), flexural strength and modulus, and dynamic mechanical analysis (DMA). The chemical treatments had a significant impact on the properties of jute fiber composites.

Sign in / Sign up

Export Citation Format

Share Document