Faculty Publications

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    Structure and properties of short Areca fiber reinforced Maize PF composites
    (2009) Mohan Kumar, G.C.
    Mechanical properties of the fibers extracted from the areca are determined and compared with the other known natural fiber coir. Further these Areca fibers were chemically treated and the effect of this treatment on fiber strength is studied. Areca fiber composite laminates were prepared with randomly distributed fibers in Maize stalk fine fiber and Phenol Formaldehyde. Composite laminates were prepared with different proportions of phenol formaldehyde and fibers. Tensile test, moisture absorption test, and biodegradable tests on these laminates were carried out. Properties of these areca-reinforced phenol formaldehyde composite laminates were analyzed and reported. © 2009 American Institute of Physics.
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    Areca Fiber Reinforced Alkali-Activated Black Cotton Soil Using Class F Fly Ash and Limestone Powder for Pavements
    (Springer Science and Business Media Deutschland GmbH, 2022) Chethan, B.A.; Ravi Shankar, A.U.
    Alkali activation has gained importance in place of cement treatment in construction due to reduced CO2 emissions. The precursors that are rich in silica, alumina, and calcium can be used for soil stabilization with a suitable alkali solution. In this investigation, 0–45% class F fly ash with a constant 5% limestone powder was used to stabilize black cotton soil. These mixes were reinforced with 0.5% areca fibers and stabilized using the alkali solution. Alkali solution was prepared using 8 molar NaOH solution and Na2SiO3 solution with Na2SiO3/NaOH of 1.5. The use of limestone powder has favoured the quick UCS gain on 3 days of room temperature curing. Fiber reinforcement has shown a significant influence on flexural strength and fatigue life improvement. Areca fibers reinforcement has resulted in enormous resistance to plunger penetration during the unsoaked CBR test. However, on further 4 days of soaking, samples lost the bonding and exhibited low CBR. The SEM images showed the compact microstructure of the set mix. The formation of cementitious products is evident from the XRD micrograms due to the dissolution of silica, alumina, calcium, and other compounds by the alkali solution. When subjected to wetting–drying and freezing–thawing durability tests, the set mixes were failed due to leaching of mineral constituents and further breaking of soil structure. Even though stabilized specimens exhibited significant strength improvement in dry conditions, they are unsuitable in wet conditions. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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    Laboratory evaluation of use of areca fibres in SMA mixes
    (Taylor and Francis Ltd., 2023) Chinnabhandar, R.K.; Kumar, H.K.; Yatish, R.G.; Ravi Shankar, A.U.
    One of the problems associated with Stone Matrix Asphalt (SMA) mixes is the drain down of binder mortar during production, transportation and placement of the mixes. A commonly adopted method to control the drain down is to add a stabilising additive such as natural, synthetic or mineral fibres to the mixture, which is also known to improve the mechanical and volumetric properties of SMA. The present study evaluates the feasibility of using areca fibres extracted from areca husk in SMA as a stabilising additive. Three SMA mixtures were prepared with Viscosity Grade VG 30 bitumen using areca fibre (SMA-AF), coconut fibre (SMA-CF) and cellulose fibre in pelletised form (SMA-PF) and their performance was compared with a control SMA mixture prepared using Polymer Modified Bitumen (SMA-PMB). The prepared SMA specimens were evaluated for volumetric and Marshall properties, workability characteristics, Indirect Tensile Strength (ITS), fatigue, rutting and moisture susceptibility. The drain down test results indicated that the fibres controlled the drain down, and the optimum fibre content was 0.3% for the mixes with fibres. All the mixtures satisfied the requirements of SMA per IRC:SP 79-2008. The statistical analysis conducted revealed that the fibre type had a significant effect on the properties of SMA mixes. The SMA-PMB and SMA-CF mixes required the least and the highest energy for compaction. Among the mixes with natural fibres, SMA-AF performed better than SMA-CF. © 2022 Informa UK Limited, trading as Taylor & Francis Group.
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    Acoustic characterization of natural areca catechu fiber-reinforced flexible polyurethane foam composites
    (John Wiley and Sons Inc, 2024) Mb, S.; Kumar, G.C.M.; Pitchaimani, J.
    The development of acoustic absorbers from natural resources is a novel approach in acoustics. In the current study, the effect of unprocessed raw areca fiber (AF) particle reinforcement on the sound absorption (SA) behavior of polyurethane (PU) foam composites is investigated. Influences of fiber weight percentage and graded distribution of fiber with varying fiber weight percentage on the SA coefficient (SAC) of the composite foams are examined through the impedance tube approach. Morphological studies are carried out with the help of FESEM images to investigate the acoustic energy dissipation mechanism of PU foam and its composites. It is found that the SA capability of the composite foam is enhanced by increased fiber weight percentage, graded distribution of fiber wt%, varying sample thickness, and air cavity length. In general, PU-AF composite specimens show a peak SA value of 0.95 around 450 Hz, which is not the case for other natural fiber results available in the literature. Theoretical results predicted using the JCA (Johnson-Champoux Allard) model agree with the experimental results. © 2023 Wiley Periodicals LLC.
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    Sound absorption performance of natural areca plant husk fibers: Experimental and theoretical study
    (SAGE Publications Ltd, 2024) Mb, S.; Gc, M.K.; Pitchaimani, J.
    Fibers extracted from plant wastes can be used for sound absorption (SA) applications in vehicles due to its lightweight and porosity. The SA capability of raw areca fibers bundle (RAFB) as a function of the density and thickness of the test specimen is analyzed. Experimental results obtained using the impedance tube approach reveal that an increase in the specimen bulk density and thickness improves the SA capability of RAFB. Similarly, hollow air volume behind the sample enhances the SA in the lower frequency range. Theoretical results predicted using the Johnson–Champoux–Allard model match well with the experimental predictions. The ability of the RAFB to absorb sound is demonstrated to be equivalent to other commercially available natural and artificial fibers by comparing the results available in the literature. © IMechE 2023.