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This study aims to investigate the optimum proportion of coconut fibre and cement suitable for rammed earth wall construction. Coconut fibres and cement can be easily incorporated into the soil mixture which adds strength and durability to the wall. This paper highlights the salient observations from a systematic investigation on the effect of coconut fibre on the performance of stabilized rammed earth blocks.

Stabilization of soil was done by adding Ordinary Portland Cement (2.5, 5.0, 7.5 and 10.0 per cent by weight of soil), whereas coconut fibre in length about 15 mm was added (0.2, 0.4, 0.6, 0.8 and 1.0 per cent by weight of soil) as reinforcement. Thirty types of mixes were created by adding different proportions of cement and fibre to locally available soil and compacting the mix at constant compaction energy in three layers with Proctor rammer.

Samples were tested for compressive strength and tensile strength, and failure patterns were analysed. The use of cement and fibre increases ultimate strengths significantly up to an optimum limit of 0.8 per cent fibre content, provides a secondary benefit of keeping material bound together after failure and increases residual strength. Benefits of fibre reinforcement includes both improved ductility in comparison with raw blocks and inhibition of crack propagation after its initial formation.

After analysing the results, it is recommended to use 0.8 per cent fibre and 5-10 per cent cement by weight of soil to achieve considerable strength. This research may add a value in the areas of green and sustainable housing, waste utilization, etc.

The purpose of this paper is to present the review of natural fibre composites as well as a specific type of fibre, i.e., sugar palm fibre and its composites.

The approach of this review paper is to present previous work on natural fibres and their composites. Then a review of several important aspects such as history, origin, botanic description, distribution, application and characterisation of sugar palm tree, and its fibre is presented. Finally a review of properties and characterisation of sugar palm composites is presented.

Findings of this review include the potential application of natural fibres and their composites for engineering application, the use of sugar palm and its fibres, as well as the suitability of sugar palm composites in engineering application after conducting review of their performance and characterisation.

The value of this review is to highlight the potential of natural fibres, natural fibre composites, sugar palm, sugar palm fibres and sugar palm composites as materials for engineering applications.

The purpose of this study is to analyse the characteristics of cellulose fibres derived from the pseudo-stems of Curcuma longa and to evaluate the properties of non-woven fabric produced using these fibres.

The fibres were extracted via a decortication method. The acquired intrinsic qualities of the fibres were used to assess the feasibility of using them in textile applications. The thermal bonding approach was used for the development of the non-woven fabric, using a hot press machine with low-melt polyester fibre as a binder.

The mean length of Curcuma longa fibres was determined to be 52.73 cm, with a fineness value of 4.00 tex. The fibres exhibited an uneven cross-sectional morphology, characterized by a diverse range of oval-shaped lumens. The fibre exhibited a tenacity of 1.45 g/denier and an elongation value of 4.30%. The fibres possessed a moisture regain value of 11.30%. The experimental non-woven fabrics had consistent weight and thickness, while exhibiting different properties in terms of tensile strength and air permeability, with Fabric C having the highest tensile strength and the lowest air permeability value.

The features of Curcuma longa fibre, obtained with the decortication process, exhibited suitability for textile applications. Three experimental non-woven fabrics comprising different compositions of Curcuma longa fibre and low-melt polyester fibre were produced. The tensile strength and air permeability properties of these fabrics were influenced by the composition of the fibres.

The purpose of this study was to characterize the fiber from Curcuma longa (turmeric) stems. The fiber’s properties were used to assess its potential for textile yarn production.

The natural fiber used in this investigation was extracted from agricultural waste through a cold water-retting process.

The Curcuma longa fiber had a crystallinity of 50%. Cellulose, hemicellulose and lignin were detected in the fibers’ Fourier transform infrared spectra. A Curcuma longa fiber bundle contains several constituent fibers. The fibers exhibited an irregular cross-section, with a variable oval shape for the lumen. The fibers of Curcuma longa averaged 30.22 cm in length. The fineness of the fibers was 6.58 Tex. In this study, Curcuma longa fibers had an 11.30% moisture regain. The tensile strength of the fibers was 19.18 g/Tex. Curcuma longa fibers showed a break elongation of 9.79%. The fiber coefficient of friction was 0.3.

Curcuma longa has characteristics that make it appropriate for industrial uses like spinning. Thus, it is possible to use Curcuma longa fiber as a raw material for textiles.

This paper aims to investigate the physical, chemical and physicochemical characteristics of rice husk on alkaline treatment.

Rice husk (RM) was alkaline treated to produce soluble (SR) and insoluble residues (IR). Each fraction was characterized and soluble fraction was used to produce nanofibres using electrospinning method.

Alkaline treatment was effective in isolating insoluble dietary fibre rich IR from the other interfering substances such as soluble dietary fibre, protein and lipids that originally present in RM and leached into SR. The problem of silica induced toxicity and indigestibility of rice husk was overcome by alkaline treatment. Alkaline treatment altered the inherent mineral content (calcium, copper, iron, potassium, magnesium, manganese, sodium, phosphorus, zinc) of rice husk, and increased physicochemical properties such as emulsification ability and stability, water holding ability, mineral binding capacity (calcium, copper, iron, zinc), and antioxidant activity. SR had been successfully electrospun into nanofibres with the addition of polyvinyl alcohol.

The paper investigated the characteristic of rice husk (RM and IR) for the development of functional foods, pharmaceutical products and new bioactives delivery system at the expense of reducing environmental liability.

In recent years, the use of earth as a material applied to construction has been adapted as an attractive alternative to modern concepts. The earth construction technique takes advantage of regional natural resources, among which are earth bricks. The purpose of this paper is to analyze the effect of the addition of coconut fibers and aloe vera on the mechanical properties of compressed earth blocks (CEB).

CEBs were manufactured from silty and clay soil (Altamira, Tamaulipas, Mexico) with biodegradable stabilizers of aloe vera and short coconut mesocarp fibers, which were compared with the conventional mixture with lime as stabilizer. The samples were subjected to compression tests (Mexican Standard NMX-C-404-ONNCC3-205), flexion (NMX-C083-ONNCCE.), abrasion (NTC-5324 3.4.3), water absorption (NMX-C-37-ONNCE-205), surface morphology and thermal properties (ASTM D5334-14).

It was found that the addition of coconut fibers has a 12% difference in flexural strength. The addition of 0.5% of coconut fibers decreases swelling by 2% with water and reduces the thermal conductivity of the material by 12%. Likewise, this mixture increases the abrasion resistance of CEB by 30%. When there is a pressure greater than 1,700 psi in the CEB, the addition of coconut fibers does increase the compressive strength of the material, showing a 34% improvement over the CEB without adding coconut fibers.

The authors show a new sustainable CEB production with aloe vera and coconut fiber that is possible for self-production with better mechanical properties than others, commonly produced in Mexico.

The aim of this research is to study the role and formation of hydration products particularly crystalline portlandite Ca(OH)2 in MWCNT-reinforced concrete at 28 days. Concrete is the largest manufactured building material in world in which cement, sand aggregates and water cement ratio plays governing role. Water–Cement ratio decides it strength, usage, serviceability and durability. As strength of concrete depends on formation of crystalline hydrates; therefore, water–cement ratio can alter formation of hydrates also. Unfortunately, concrete is the most brittle material and to overcome brittleness of conventional concrete is tailored with some fibers. Till now, multiwalled carbon nano tubes are the most tensile and strongest materials discovered. Addition of multiwalled carbon nano tubes changes basic properties of conventional concrete. Therefore, it is important to evaluate formation of crystalline hydrates in multiwalled carbon nano tube–reinforced concrete by micro structure analysis.

Till now, multiwalled carbon nano tube–reinforced concrete has not been analyzed at micro structure level. To accomplish the objective, four concrete mixes with 0.45, 0.48, 0.50 and 0.55 water–cement ratio having 0.5 and 1% multiwalled carbon nano tubes incorporated by weight of cement, respectively. For hardening property analysis, compressive strength was obtained by crushing cubes; flexural strength was obtained by three-point loading; and split tensile strength was obtained by splitting cylindrical specimens. For analyzing role and formation of crystalline portlandite Ca(OH)2 hydrates, X-ray diffraction test was conducted on 75-µ dust of each mix. Scanning electron microscopy analysis was performed on fractured samples of crushed cubes of multiwalled carbon nano tube–reinforced concrete samples to check aggloremation.

It was observed multiwalled carbon nano tubes successfully enhanced compressive strength, flexural strength and split tensile strength by 8.89, 5.33 and 28.90%, respectively, in comparison to reference concrete at 0.45 water–cement ratio and 0.5% multiwalled carbon nano tubes by weight of cement. When its content was increased from 0.5 to 1% by weight of cement compressive strength, flexural strength and split tensile strength diminished by 2.04, 0.32 and 1.18%, respectively, at 0.45 water–cement ratio. With the increment of water–cement ratio, overall strength decreased in all mixes, but in multiwalled carbon nano tube–reinforced concrete mixes, strength was more than reference mixes. In reference, concrete at 0.45 water–cement ratio crystalline portlandite Ca(OH)2 crystals are of nano metre size, but in carbon nano tube–reinforced concrete mix having 0.45 water–cement ratio and 0.5% multiwalled carbon nano tubes by weight of cement, its size is much smaller than reference mix, thereby enhancing mechanical strength. In reference, concrete at 0.55 water–cement ratio size of crystalline portladite Ca(OH)2 crystals is large, but with incorporation of multiwalled carbon nano tubes, their size reduced, thereby enhancing mechanical strength of carbon nano tube–reinforced concrete having 0.55 water–cement ratio and 0.5 and 1% multiwalled carbon nano tubes by weight of cement, respectively. Also at 1% multiwalled carbon nano tubes by weight of cement, agglomeration and reduction in formation of crystalline portlandite Ca(OH)2 crystals were observed. Multiwalled carbon nano tubes effectively refine pores and restrict propagation of micro cracks and act as nucleation sites for Calcium-Silicate-Hydrate phase. Geometry of crystalline axis of fracture for portlandite Ca(OH)2 crystals is altered with incorporation of multiwalled carbon nano tubes. Crystalline portlandite Ca(OH)2 crystals and bridging effect of multiwalled carbon nano tubes is governing factor for enhancing strength of multiwalled carbon nano tube reinforced concrete.

Multiwalled carbon nano tube–reinforced concrete can be used to make strain sensing concrete.

Change in geometry and size of axis of fracture of crystalline portladite Ca(OH)2 crystals with incorporation of multiwalled carbon nano tubes.

Nowadays, hydroponic cultivation represents a widely used agricultural methodology. The purpose of this paper is to study comparatively on hydroponic substrates. This study is highlighting the best substrate to be involved in hydroponic systems, considering its costs and its sustainability.

Seven substrates were evaluated: rock wool, perlite, vermiculite, peat, coconut fibres, bark and sand. Life cycle assessment (life cycle inventory, life cycle impact assessment (LCIA) and life cycle costing (LCC)) was applied to evaluate the environmental and economic impact. Through the results of the impacts, the carbon footprint of each substrate was calculated.

Perlite is the most impacting substrate, as highlighted by LCIA, followed by rock wool and vermiculite. The most sustainable ones, instead, are sand and bark. Sand has the lower carbon footprint (0.0121 kg CO₂ eq.); instead, bark carbon footprint results in one of the highest (1.1197 kg CO₂ eq.), while in the total impact analysis this substrate seems to be highly sustainable. Also for perlite the two results are in disagreement: it has a high total impact but very low carbon footprint (0.0209 kg CO₂ eq.) compared to the other substrates. From the LCC analysis it appears that peat is the most expensive substrate (€6.67/1,000 cm³), while sand is the cheaper one (€0.26/1,000 cm³).

The LCA and carbon footprint methodologies were applied to a growing agriculture practice. This study has highlighted the economic and environmental sustainability of seven substrates examined. This analysis has shown that sand can be the best substrate to be involved in hydroponic systems by considering its costs and its sustainability.

This paper aims to investigate the current state of biocomposites used in fused deposition modelling (FDM) with a focus on their mechanical characteristics.

The study presents a variety of biocomposite materials that have been used in filaments for 3D printing by different researchers. The process of making filaments is then described, followed by a discussion of the process parameters associated with the FDM.

To achieve better mechanical properties of 3D-printed parts, it is essential to optimize the process parameters of FDM while considering the characteristics of the biocomposite material. Polylactic acid is considered the most promising matrix material due to its biodegradability and lower cost. Moreover, the use of natural fibres like hemp, flax and sugarcane bagasse as reinforcement to the polymer in FDM filaments improves the mechanical performance of printed parts.

The paper discusses the influence of critical process parameters of FDM like raster angle, layer thickness, infill density, infill pattern and extruder temperature on the mechanical properties of 3D-printed biocomposite.

This study has assessed the thermal performance of locally fabricated bio-based building envelopes made of coconut and corn husk composite bricks to reduce building wall heat transmission load and energy consumption towards green building adaptation.

Samples of coconut fiber (coir) and corn husk fiber bricks were fabricated and tested for their thermophysical properties using the Transient Plane Source (TPS) 2500s instrument. A simulation was conducted using Dynamic Energy Response of Building - Lunds Tekniska Hogskola (DEROB-LTH) to determine indoor temperature variation over 24 h. The time lag and decrement factor, two important parameters in evaluating building envelopes, were also determined.

The time lag of the bio-based composite building envelope was found to be in the range of 4.2–4.6 h for 100 mm thickness block and 10.64–11.5 h for 200 mm thickness block. The decrement factor was also determined to be in the range of 0.87–0.88. The bio-based composite building envelopes were able to maintain the indoor temperature of the model from 25.4 to 27.4 °C, providing a closely stable indoor thermal comfort despite varying outdoor temperatures. The temperature variation in 24 h, was very stable for about 8 h before a degree increment, providing a comfortable indoor temperature for occupants and the need not to rely on air conditions and other mechanical forms of cooling. Potential energy savings also peaked at 529.14 kWh per year.

The findings of this study present opportunities to building developers and engineers in terms of selecting vernacular materials for building envelopes towards green building adaptation, energy savings, reduced construction costs and job creation.

This study presents for the first time, time lag and decrement factor for bio-based composite building envelopes for green building adaptation in hot climates, as found in Ghana.