Development of Eco-Friendly Biomaterials: Recycled Thermoplastics Reinforced with Short Natural Cane and Palm Fibers

This research looked into how steel fiber type and concentration influence Steel Fiber Reinforced Concrete (SFRC) mechanical properties. According to tests, the percentage of steel fibers in SFRC is directly related to compressive, flexural, splitting tensile, and direct tensile strength. Straight and hooked steel fibers with the same aspect ratio, 13 mm in length and 0.2 mm in width of straight steel fibers, and 35 mm long and 0.55 mm wide hook-end steel fibers were utilized. Three different percentages of fiber were used: 0.5, 1, and 1.5% by volume. Seven variants of concrete with different types and different percentages of steel fiber were created and evaluated. At 0.5, 1.0, and 1.5% fiber content, the compressive strength of a cube reinforced with hook steel fibers increased by 1.41, 11.52, and 20.81%, respectively, while the compressive strength of a cube reinforced with straight steel fibers increased by 7.27 and 20%, and 21.4% for the same percentages of steel hooked fiber. This indicates that the straight steel fibers are more effective than the hook steel fibers when increasing the compressive strength of the (SFRC). This means that (pressure force increases, albeit gradually). The concrete's splitting tensile strength may be significantly increased by introducing straight and hook steel fiber into the mixture. The tensile strength is improved by (52.78, 69.44, 122.22%) and (44.44, 62.8, 94.44%) when compared to the control concrete sample. Straight steel fibers increased flexural strength by (44.23, 61.54, 86.54%) compared to the control sample, and hook steel fibers increased flexural strength by (11.54, 28.85, 55.77%). When straight fibers are introduced to the control concrete sample, the direct tensile strength increases by about (54.17, 87.5, 162.5) %, and when hook fibers are added, the direct tensile strength increases by (45.83, 75, and 150%).

This article focuses on the evaluation of the resistance of mortars to indirect tension and compression, simple and reinforced, with different percentages of steel fiber. The aim is to find resistant and economical solutions to reinforce informal housing, through the use of plaster that improves the general characteristics of a masonry. Masonry constructed in an informal or artisanal manner has a high degree of structural vulnerability. First, the indirect tensile strength and displacements supported by simple and reinforced mortars are compared, where it is observed that reinforced mortars offer greater strength and deformation capacity as a function of the percentage of fiber. Then, the compressive strength is compared, where the reinforced mortars also show adequate results. In terms of economics, the reinforced mortar presents disadvantages due to the cost of the fibers; in the percentages studied in this article (10, 15, 20 and 25%), the use of reinforced mortars for informal housing is not so attractive; it is recommended to develop similar investigations with different percentages of fiber.

Physico-mechanical and morphological behavior of hydrothermally treated plant fibers in cementitious composites

Application of MATLAB software for water absorption test, which entails the rate by which a material diffuses and retain water molecule, on epoxy reinforced with coconut shell fiber (CSF), aluminum oxide (Al2O3), and silicon carbide (SiC) composites have been investigated. Five specimens (E, S1, S2, S3 and S4) were developed using compression molding on different percentage of fibers. The water absorption test was conducted using suitable American Society for Testing and Material (ASTM) which involves different water solutions. It was observed that sample ‘E’ shows maximum water absorption maybe due to absence of reinforced fibers. Specimen S1 indicated less water absorption, maybe due to presence of natural filler. Sample S4 shows trend on least water absorption, maybe due presence of higher percentage of natural synthetic fibers. Validation of the experiments using 2020 Commercial License Model MATLAB software, which were compared with the experimental result using the root mean square error (RMSE) statistical parameter and graph of point of intercept. The predicted data developed through the MATLAB software, established 95% confidence bounds on RMSE, which indicated 0.012 range of standard deviation between the experimental and simulation results, which avoids the under fitting and over fitting problem, also, when compared using a graph of point intercept, followed the same trend of result from the experiment.

Laboratory studies on effect of fiber content on dynamic characteristics of municipal solid waste

The disposal of 2011 Japan earthquake waste has become an important issue in Japan and it is not realistic or economical to send all of these wastes to landfill sites, due to limited space, high costs, and related environmental issues. In sustainable geotechnical applications, mixing of the separated soils from disaster wastes with additives (e.g., cement and fiber) is required to improve their strength and stiffness characteristics. In this study, monotonic triaxial drained compression tests are performed on medium dense specimens of Toyoura sand-cement-fiber mixtures with different percentages of fiber and cement (e.g., 0–3%) additives. The experimental results indicate that behavior of the mixtures is significantly affected by the concentration of fiber and cement additives. Based on a comprehensive set of test results, modifications to the series of equations were developed that can be used to evaluate the shear modulus and mobilized stress curves at small-strain levels. The experimental results and model comparison show that the elastic threshold strain (γe), reference strain (γr), increases with fiber and cement additives. In addition, the range of curvature parameter, from 0.88 to 1.0, provides a good comparison with the results of small-strain measurements. Overall, the comparison of the results and model shows that the small-strain measurements obtained using local strain transducers fall within the range of model upper and lower bound curves. The results of the unreinforced, fiber, and cemented sand shows a close agreement with the model mean curve, but fiber-reinforced cemented sand shows a good comparison with model upper bound.

In this experimental study, we are interested in local fiber wavy chips derived from waste machining steel parts. This work has focused on studying the mechanical behavior of reinforced concrete, with this type of fiber, in direct tensile. Direct tensile tests were carried out on samples in free weights section and square (100x100) mm2. This test involves the design and the implementation of special mounting specimens on the tensile machine type Ibertest. Five (05) fibers percentages were retained in (W = 0.5%. W = 0.8%, W = 1%, W = 1.2%, W = 1.5% with W: volume fraction of added fiber) and two (02) concrete witness whose report on gravel sand is equal to: S / G = 0.8 and S / G = 1. The fibers have been characterized to the strength and tear by the tensile test. The interest lies in optimizing the fiber length and the number of undulations to use in a cement matrix, which will improve the mechanical properties especially tensile strength and post-cracking behavior. The comparison of different results obtained in direct tension on different percentages of fiber, as well as two reports showed that the fibers have conferred a significant ductility to the material after cracking of concrete for different percentages of fiber and a strength for improving the S / G = 0.8.

The fundamental knowledge of flow behaviour is essential in producing various plastic parts injection moulding process. Moreover, the adaptation of advanced polymer-nanocomposites such as polypropylene-nanoclay with natural fibres, for instance Gigantochloa Scortechinii may boost up the mechanical properties of the parts. Therefore, this project was proposed with the objective to optimise the processing condition of injected mould polypropylene-nanoclay-Gigantochloa Scortechini fibres based on the flow behaviour, which was melt flow index. At first, Gigantochloa Scortechinii fibres have to be preheated at temperature 120°C and then mixed with polypropylene, maleic anhydride modified polypropylene oligomers (PPgMA) and nanoclay by using Brabender Plastograph machine. Next, forms of pellets were produced from the samples by using Granulator machine for use in the injection moulding process. The design of experiments that was used in the injection moulding process was Taguchi Method Orthogonal Array -L934. Melt Flow Index (MF) was selected as the response. Based on the results, the value of MFI increased when the fiber content increase from 0% to 3%, which was 17.78 g/10min to 22.07 g/10min and decreased from 3% to 6%, which was 22.07 g/10min to 20.05 g/10min and 3%, which gives the highest value of MFI. Based on the signal to ratio analysis, the most influential parameter that affects the value of MFI was the melt temperature. The optimum parameter for 3% were 170°C melt temperature, 35% packing pressure, 30% screw speed and 3 second filling time.

This pilot study aims to develop a self-healing asphalt through microwave heating, to reduce processing time, save energy and allow real commercial applications in a near future. Asphalt based composites were produced with different percentages of steel short fibers, obtained from the cutlery industry, to serve as a heat source for microwave radiation. Structural characteristics, morphology, and thermic behavior of the short steel fibers were characterized through X-ray Diffraction, X-ray Fluorescence, Scanning Electron Microscopy and Thermogravimetric Analysis, that was also used to verify the relation between mass variation and temperature of the asphalt-based composite. Temperature was monitored during micro wave heating to determine the heating rate of the composites with different percentage of fibers. Brookfield viscosity, penetration, ductility, softening point and density tests were carried out to characterize physical properties of the most representative asphalt-based composite. Results show the feasibility to use microwave heating in the production of the composite, indicating potential for future application as self-healing asphalt and pavement repair.

Mechanical strength and water penetration depth of palmyra fibre reinforced concrete

The composites of carbon fiber with EVA, NBR, and their blends have been made by melt mixing technique. Stress–strain plots of different composites show that the necking phenomenon is increasing with the increase in fiber concentration in the polymer matrix. The scanning electron microscopic analysis and swelling study exhibit poor interaction between the short carbon fiber and polymer matrix. The decrease in DC resistivity with the increase in short carbon fiber concentration has been explained on the basis of percolation theory. EMI SE increases slightly with the increase in frequency of electromagnetic radiation but increases sharply with the increase in fiber concentration. EMI SE also depends on blend composition and increases with the increase in EVA concentration in the blend. Return loss is decreasing but absorption loss is increasing with the increase in fiber loading. A linear relationship is observed between the EMI SE and thickness of the composites. The EMI SE is found to increase exponentially with the increase in conductivity of the composite. The permeability value is decreasing with the increase in frequency as well as fiber loading. Thermal properties of the composites have been evaluated by thermogravimetric analysis and dynamic mechanical analysis. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers

Straight Retamo Fiber (telinemonspessulana) was mixed in a polymer matrix formed by low density polyethylene (LDPE) and high impact polystyrene (HIPS) in a 70:30 ratio. The natural fiber was subjected to size reduction between 1700 and 850 µm; surface treatment mercerization was performed; the moisture content was 0.17%. The thermo gravimetric analysis (TGA) showed that the treated fiber has stability at 200.53 °C. The preparation of the compound was performed in an internal mixer with the samples being obtained by compression molding. The effect of crosslinking agent was evaluated: dicumyl peroxide (DCP) in compounds with various percentages of fiber: 0; 10; 25; 50 phr. The addition of DCP (1 phr) in the compounds significantly improved tensile properties compared to similar concentrations of fiber; however, this difference in property values progressively decreased when the amount of fiber approximated 50 phr. The increase in fiber concentration negatively affected the tensile properties, except for the modulus of elasticity and fluence resistance. The main cause is the low interfacial adhesion between the natural fiber and the polymer matrix, clearly evidenced in the SEM images.

The implementation of natural and artificial fibers as a stabilization technique for construction materials has developed new trends in the last decade and has generated functionality. This research evaluates the implementation of fibers derived from polypropylene as element of soil reinforcement. These fibers have the advantage that they do not have biodegradation or oxidation processes, which makes it a cost-effective and environmentally friendly option. The fibers are used to reinforce samples of silty soil derived from a slope deposit. Specifically, the behavior of the soil under unconfined compressive stresses and penetration stresses in the CBR test is evaluated. Polypropylene fibers derived from industrial processes were used, bringing them to the same size and using the same proportion of these in the soil samples, different percentages of fiber with respect to soil weight were evaluated to identify which was optimal in the experiment. Additionally, the process of formation of the samples was controlled to maintain close values of maximum dry density and optimum moisture content. A comparison and analysis that quantifies the contribution of these fibers is proposed. The results obtained are supported by the laboratory tests performed. These results show that the reinforced material has higher unconfined compressive strength, higher ductility, and higher resistance to penetration. It is proposed to evaluate the effect of the fiber arrangement in future research.

This paper focuses on evaluating the mechanical recycling potential of poly(lactic acid) (PLA) biocomposites reinforced with agave fibers (AF). The biocomposites were prepared by extrusion using 5, 15, and 30 wt.% of agave fibers and reprocessed up to eight times. The results show that the fiber dimensions substantially decrease during reprocessing, especially after the first extrusion cycle, followed by a more gradual decrease in each subsequent cycle. The melt flow index (MFI) and the mechanical properties (except impact strength) tend to decrease as the fiber concentration increases. On the other hand, the glass transition temperature ( T g) and the crystallinity ( X c) of the biocomposites increased with increasing fiber concentration. It is important to highlight that closed-loop reprocessing does not significantly affect the overall behavior of the biocomposites under the conditions investigated. Therefore, PLA reinforced with AF is suitable for primary recycling since the final properties are mainly influenced by the fiber concentration and less by the number of reprocessing cycles.

Lung tissue from 221 definite and probable cases of malignant mesothelioma reported to the Australian Mesothelioma Surveillance Program from January 1980 through December 1985 and from an age-sex frequency matched control series of 359 postmortem cases were examined by light microscopic (LM) and analytical transmission electron microscopic (TEM) analysis and energy dispersive x-ray analysis (EDAX). Concentrations of total fibers (coated and uncoated) (LM), crocidolite, amosite, chrysotile, and unidentified amphibole (TEM) (fibers/g dry lung tissue) were measured. Fiber concentrations less than 10 microns in length and greater than or equal to 10 microns in length were separately quantified. By comparing cases (221) and controls (359 LM, 103 TEM), odds ratios for increasing fiber concentrations compared with less than 15,000 fibers/g (LM) and less than 200,000 fibers/g (TEM) (the respective detection limits) were calculated. Univariate analyses showed statistically significant dose-response relationships between odds ratio and fiber concentration for all fiber concentration measures. The relationship between log(odds ratio) and log(fiber concentration) was linear. Multiple logistic regression analysis showed that a model containing crocidolite greater than or equal to 10 microns, amosite less than 10 microns, and chrysotile less than 10 microns as explanatory variables best described the data. The odds ratios for a X10 increase in fiber concentration (fibers/micrograms) were as follows: crocidolite greater than or equal to 10 microns, 29.4 (95% confidence interval [CI], 3.6 to 241); chrysotile less than 10 microns, 15.7 (95% CI, 6.1 to 40); amosite less than 10 microns, 2.3 (95% CI, 1.0 to 5.3). An additive risk model gave similar results. In a subgroup of cases and controls with only chrysotile in the lungs, a significant trend in odds ratio with increasing fiber content was found.