Jute Fibre-reinforced Polymer Research Articles

Stress-strain behaviour of pre-damaged concrete confined with natural fibre reinforced polymer

In recent years, using environmentally friendly construction materials has become a new trend in structural engineering. This research presents the application of natural fibre reinforced polymer (NFRP) composites for repairing damaged structural concrete members. The compressive behaviour of pre-peak damaged concrete confined with two types of NFRP composites was investigated. The tensile properties of jute fibre reinforced polymer (JFRP) and sisal fibre reinforced polymer (SFRP) were examined and compared with those of carbon fibre reinforced polymer (CFRP) using coupon tests. Subsequently, a series of pre-damaged concrete cylinders, confined with JFRP, SFRP, and CFRP, were subjected to uniaxial compression tests. The results showed that JFRP and SFRP are effective in providing confinement to pre-peak damaged concrete. The strength and ductility of pre-peak damaged concrete confined with NFRP increased with the number of NFRP layers. The cost-effectiveness of FRP-confined concrete was also evaluated, with JFRP being the most economically efficient. The eco-strength efficiency (ESE), defined as the increased compressive strength per unit of CO2 emissions, shows that JFRP is the most effective. This highlights JFRP's potential for sustainable construction. Finally, the compressive strength models were proposed. The models demonstrate improved accuracy in predicting the peak compressive strength of pre-peak damaged concrete confined with NFRP compared to existing models.

Jute Fibre Reinforced Polymer Composites in Structural Applications: A Review

Jute Fibre Reinforced Polymer Composites in Structural Applications: A Review

Strength, durability and finite element analysis of hybrid jute/basalt fiber reinforced polymer confined concrete column under axial compression

Implementing retrofitting measures for a civil structure may guarantee its ongoing safety and operation, while also extending its lifespan. The present investigation focused on the examination of compressive axial loads on concrete columns that were confined by natural fiber reinforced polymer (FRP). In particular, concrete cylinders confined with jute and basalt fiber epoxy composites were evaluated for their strength and durability. Various strength tests were conducted on unconfined and, jute, basalt, and hybrid jute-basalt FRP confined concrete cylinders with varying thicknesses of the FRP layers. Effectiveness of these natural FRP systems in providing external confinement to concrete columns in various environmental conditions were investigated, including exposure to acidic, alkaline, seawater, and potable water environments. Test results demonstrated that external confinement with hybrid FRP wraps, i.e. with both jute and basalt fibers, enhanced the load-bearing and energy absorption capacities by 63.64 % and 287 %, respectively. The confinement effectiveness of FRP wrapped specimens were 213 %, 164 %, 166 % and 163 % respectively compared to the unconfined specimens after exposure to acidic, alkaline, seawater and potable water environments. These impressive outcomes may be ascribed to the intrinsic rigidity of hybrid fibers. Furthermore, a finite element analysis (FEA) model of FRP confined concrete columns was performed using ABAQUS software calibrated with the experimental data. A close agreement between the experimental results and the adopted numerical model was observed. The outcome of the study suggests that the confinement with natural FRP can be used as a prominent retrofitting technique for columns in a variety of environments which can thus enhance the durability and sustainability of civil constructions.

Optimal Shear Strengthening of Severely Deficient RC Beam Using JFRP Laminate with Anchor

High-strength jute fibre-reinforced polymer (JFRP) laminates have recently been introduced to strengthen RC beams against shear. In contrast to synthetic-based composites, JFRP laminates would be more ductile, compatible with steel shear rebar and effective in reducing debonding due to their lower modulus of elasticity. The prime objective of this research was providing an optimal solution to strengthen a severely deficient RC beam against shear using an externally bonded JFRP laminate with anchor. Fabrication of the JFRP laminate was carried out with the maximum fibre content of 37.5% to obtain high tensile strength. Five full-scale RC beam specimens were cast. Shear strengthening was done by an externally bonded JFRP laminate with double connector, multiple connector and embedded-bar anchor systems. The dimensions of JFRP laminate were obtained based on proposed guidelines. Based on the experimental test, the average tensile strength of the fabricated JFRP laminate was found to be 162 MPa. Results also showed that the JFRP laminate with multiconnector anchor increased the maximum shear capacity of deficient RC beams by 89% and the beams had failed by the fracture of laminate. Beams strengthened with embedded-bar anchor had shown flexural ductile failure. Both beams failed after yielding of flexural bar. The proposed guidelines could be used for shear strengthening of severely deficient beams to enhance the maximum shear capacity using full strength of JFRP laminate with anchor. KEYWORDS: RC beam, Shear strengthening, JFRP laminate, Anchor, Optimal design

A comprehensive study on the effect of hybridization and stacking sequence in fabricating cotton-blended jute and pineapple leaf fibre biocomposites

Developing biocomposites by hybridization, which is the combination of two or more materials, can be a potential solution for improving material recyclability and sustainability. This study focuses on creating a hybrid biocomposite reinforced with cotton-blended pineapple leaf fibre (PALF) fabric (174 GSM) and jute fibre fabric (265 GSM) which are thrown away by textile factories. The mechanical, moisture absorption, and vibration characteristics of four stacking sequences of hybrid composites and two unhybridized composites were analyzed. Results indicated that hybridization improved tensile and flexural characteristics compared to pineapple leaf fibre reinforced polymer (PFRP) composites. The jute fibre reinforced polymer (JFRP) composite exhibited the maximum tensile strength of 35.16 MPa, while the hybrid composites achieved a maximum of 32.16 MPa. Among the hybrid composites, jute layers on the outer plies (4P5J-2) demonstrated the maximum tensile modulus of 1.315 GPa. Additionally, the hybrid composite with three layers of jute plies between alternating layers of jute-pineapple plies showed the highest elongation at 15.94%. Among the hybrids, alternate stacking of jute/PALF plies (4P5J-1) gave a maximum flexural strength of 44.36 MPa, which is similar to JFRP (44.91 MPa) and a 78.57% increase in flexural modulus compared to PFRP composite, despite having the lowest tensile strength. Although the JFRP composite exhibited the highest impact strength, the hybrids still outperformed the PFRP composites. With hybridization, moisture absorption decreased, with a maximum of 29.50% compared to the JFRP composite. Furthermore, due to the spiral-like orientation of the yarns, stacking PALF plies on the outside can cause critical damping. Therefore, it is shown in this paper that both hybridization and stacking sequence can significantly influence composite performance. These findings also implies the utilization of textile industry's natural fibres to develop hybrid composites for automotive applications, like brake and accelerator pedals, for a greener future and effective waste material utilization.

Effect of Wrapping on Post-Tensioned Beams Strengthened with Natural Sisal and Jute FRP Using Finite Element Analysis

Existing buildings are retrofitted to formulate them to be more resistant to seismic activity, earth motion, and other natural disasters. Many available reinforced concrete buildings across the globe are in desperate need of rehabilitation, repair, or replacement owing to degradation caused by a variety of reasons such as corrosion, lack of detailing, and failure of beam-column bonding, among others. In the construction sector, fibre reinforced polymer (FRP) composites have been recognized as a potential option for repairing and increasing the strength of existing structures. In this study, comparisons are done in terms of load bearing capability of the beams for configurations between FE model predictions and field data (experimental). To assess the FRP retrofit, structural responses for strengthened and control post tensioned concrete (PTC) beams are compared, with strengthening using various wrapping methods. The load bearing capacities of the beams retrofitted with sisal and jute fibre employing strip and full wrapping procedures around all four sides is increased by 35.55 percent and 42.85 percent for sisal FRP and 7.14 percent and 12.01 percent for jute FRP, respectively, as compared to the control specimen. The FRP retrofit model is expected to result in a considerable increase in structural performance.

Compressive Behavior of Predamaged Concrete Cylinders Repaired with Jute and Basalt FRP Composites: A Comparative Study

Natural fibers have become a research hotspot in composite materials recently. This study investigated the axial compressive behavior of predamaged concrete repaired by jute fiber–reinforced polymer (JFRP) composites. Basalt FRP (BFRP) was also utilized to repair the predamaged concrete for comparison. Thirty FRP-jacketed concrete cylinders with a diameter of 150 mm and a height of 300 mm were designed and fabricated. Plain concrete cylinders were axially preloaded to three predamage levels, then repaired by JFRP and BFRP composites, and reloaded to evaluate the compressive behavior after repair. The results showed that the predamage of concrete had a noticeable adverse effect on the compressive behavior of JFRP- and BFRP-repaired concrete. Compared with the JFRP-jacketed intact concrete, the compressive strength and initial elastic modulus of the JFRP-repaired predamaged concrete decreased by 6%–18% and 16%–54%, respectively. However, the compressive strength and ultimate strain of the predamaged concrete were still improved by 5%–41% and 82%–291% after JFRP repair, respectively, when compared with those of the plain concrete. On the contrary, the ultimate axial strain and lateral strain capacities of JFRP- and BFRP-repaired concrete were insignificantly affected by the concrete predamage. Under similar confinement ratios, the compressive strengths of JFRP- and BFRP-jacketed intact concrete were close to each other, whereas the axial strain–lateral strain relationship and the variations of the Poisson’s ratios were highly dependent on the FRP types and the number of FRP layers. Based on the test results and data collected from the open literature, an ultimate strength model, an ultimate axial strain model, and a stress–strain relationship model were newly developed for JFRP-repaired predamaged concrete.

Review on the Development of Jute Polyethylene Nanocomposites as a Function of Fiber Chemical Treatments

: The research on jute fiber reinforced polymer composites is an emergent concern with the development of new materials due to their significant properties like economical, partially biodegradable, and environment friendly. It is wondered that the hydrophilic nature of jute fiber negatively affects the interfacial interaction with hydrophobic polymeric materials in the composite, which then affects the resultant mechanical, microstructural and physico-chemical absorption properties. In order to overcome this fact, researchers have carried out some techniques for fiber surface chemical treatments. On the other hand, due to the low processing costs and design flexibility, thermoplastics deal many benefits over thermoset polymers, and polyethylene shows excellent processing behaviors such as low density, low cost, considerable flex life, outstanding surface hardness, scratch resistance and good electrical insulator. Besides the traditional thermoplastic and thermosetting polymers, montmorillonite nanoclay is also receiving attention to manufacturing fiber polymer nanocomposites for industrial and household applications as well. This review is considered to highlight the progress of jute fiber reinforced polymer nanocomposites. The study also focuses on the several features of jute polymer composites and nanocomposites as a function of fiber chemical treatments.

Jute Fiber-Reinforced Polymer Tube-Confined Sisal Fiber-Reinforced Recycled Aggregate Concrete Waste.

In this study, the compressive performance of sisal fiber-reinforced recycled aggregate concrete (SFRAC) composite, confined with jute fiber-reinforced polymer (JFRP) tube (the structure was termed as JFRP–SFRAC) was assessed. A total of 36 cylindrical specimens were tested under uniaxial compression. Three major experimental variables were investigated: (1) the compressive strength of concrete core (i.e., 25.0 MPa and 32.5 MPa), (2) jute fiber orientation angle with respect to the hoop direction of a JFRP tube (i.e., β = 0°, 30° and 45°), and (3) the reinforcement of sisal fiber (i.e., 0% and 0.3% by mass of cement). This study revealed that the prefabricated JFRP tube resulted in a significant enhancement of the compressive strength and deformation ability of RAC and SFRAC. The enhancements in strength and ultimate strain of the composite columns were more pronounced for concrete with a higher strength. The strength and ultimate strain of JFRP-confined specimens decreased with an increase in fiber orientation angle β from 0° to 45°. The sisal fiber reinforcement effectively improved the integrity of the RAC and reduced the propagation of cracks in RAC. The stress–strain behaviors of JFRP–RAC and JFRP–SFRAC were predicted by the Lam and Teng’s model with the revised ultimate condition equations.

The Influence of the Curing Conditions on the Behavior of Jute Fibers Reinforced Concrete Cylinders

This paper presents an innovative method of reinforcement of concrete based on the use of the Jute fibers composites. These renewable raw bioresource fibers are available at a low cost. Moreover, they can be compared to Glass Fiber-Reinforced Polymer (GFRP) by enhancing the resistance of Jute Fiber-Reinforced Polymer (JFRP), while improving the compatibility between the fiber and the resin. For that purpose, this paper presents an experimental study that evaluates the influence of the curing conditions (time and temperature) on the behavior of JFRP laminates and concrete members strengthened by JFRP. The curing conditions at 30 °C for 2h 30min and at 50 °C for 1 h were the only two parameters studied and determined on the basis of Sikadur 330 properties and preliminary tests. Through the experimental tests, the maximum load capacity and observed failure modes are investigated. The results indicated that the curing at 30 °C for 2h 30min is the optimum curing condition. In addition, a low difference in the maximum load capacity was noted in the case of 50 °C. As to the failure modes, all the specimens cured with additional heat before being left under room conditions, have shown the ductile mode failure, especially in the case of specimens cured at 30 °C during 2h 30min. The analytical model conducted in this paper predicts the elastic modulus depending on temperature. The obtained results and proposed model can be used as input parameters in the analysis and design of externally strengthened members with Jute FRP composites.

Simulation of centrally loaded GrFRP and analysis of fixed (both ends) supported stress concentrated JFRP beam

Natural fiber polymer composites are generally used in the furniture, home appliances, construction works. Present work is based on the simulation of the Graphite Fiber Reinforced Polymer (GrFRP) composite laminates through numerical model. In simulation we get maximum 7% error with the available experimental results. Analyzed a beam which is made from natural fiber reinforced polymer composites. It consists of eight stacks of natural fiber lamina, a central hole, both the ends supported as fixed and loaded by a uniformly distributed load (UDL). A numerical tool have been developed to analyze the Jute Fiber Reinforced Polymer (JFRP) composites. In this analysis, four different sequencing pattern of lamina has been used. The numerical failure index and failure strength for the different tacking sequences of lamina is determined. The maximum failure strength for the (60 °/-60 °/60 °/-60 °)s laminate is 22.51MPa. We found that in the simulation the results of the model are very close to experimental results. Its method of analysis is more convenient and economical over the experimental work. Therefore, the method was found very suitable for modelling and analysis in future.

Flexural behavior of corroded reinforced concrete beam strengthened with jute fiber reinforced polymer

Fiber-reinforced polymer (FRP) is a revolutionary breakthrough in the history of structural engineering innovation due to its unique characteristics to strengthen and repair the deficient reinforced concrete structures. This paper aimed at evaluating the flexural characteristics of jute fiber reinforced polymer (JFRP) bonded reinforced concrete beams. The influence of the test variables comprised of strengthening scheme and corrosion rate for reinforced concrete (RC) beams. The experimental study comprised of casting six RC beams and testing them in flexure loading. To determine the flexural response of RC beams, three beams were fabricated with JFRP laminate having a level of corrosion of 0%, 7.5%, and 15%, whereas three beams were designated as control beams having same corrosion levels with no JFRP. Test results indicated that all JFRP strengthened beams exhibited increased ultimate load, yield load, first cracking load, and lower ductility index compared to control beams. The results also revealed that JFRP strengthening technique improved the flexural strength of the corroded beams efficiently, albeit the ultimate load of the beams diminished with higher corrosion level. Analytical calculations were carried out for quantifying the flexural characteristics and mass loss of beams which provided a good agreement with the test results.

Mechanical characterization and optimization of delamination factor in drilling bidirectional jute fibre-reinforced polymer biocomposites

In this comprehensive investigation, we evaluate the mechanical properties and the effect of drilling parameters (spindle speed, 355, 710 and 1400 rev/min; feed rate, 50, 108 and 190 mm/min; and the tool diameter, 5, 7 and 10 mm) as a function of the cutting process on the delamination factor when drilling jute fabrics reinforced epoxy matrix biocomposites. The study is carried out using different drill geometries and material (HSS_TiN, HSS and brad and spur drill bits). The design of experiment is developed by the application analysis of variance (ANOVA). The response surface methodology (RSM) and artificial neural networks (ANN) are applied to validate the results obtained during the experiment and to predict the behaviour of the structure under any cutting condition. Result analysis showed the superiority of the ANN model over the RSM model, while the feed rate had a significant contribution on spindle speed and diameter. The optimum conditions obtained for the Fd factor were a feed rate of 51 mm/min, a spindle speed of 1160 rev/min and a drilling diameter of 5 mm.

Effects of Heat Treatment on Mechanical Properties of Jute Fiber–Reinforced Polymer Composites for Concrete Confinement

Some natural fibers such as jute which have high tensile strength can be applied in natural fiber-reinforced polymer (FRP). Natural cellulose fibers are hydrophilic, resulting in lower reinforcement performance. Heat treatment can reduce water content in natural fibers and possibly improve the properties of natural FRP in terms of enhancing fiber and polymer composite action. This paper presents an improvement of jute fiber–reinforced polymer (JFRP) composites by heat treatment. The heat treatment conditions (i.e., temperature and duration) were considered. Coupons of heated JFRPs were tested to investigate their tensile properties. The application of JFRP on confinement was investigated by compression tests on concrete cylinders with JFRP wrapping. The experimental results indicated that a suitable heat treatment condition of 80°C for 24 h can significantly increase the tensile strength of JFRP coupons and the compressive strength of JFRP-confined concrete. The testing results of concrete confinement can be used to validate the existing predicting equations for confined compressive strength. In addition, a new equation was proposed for the effect of heat treatment of JFRP.

Effect of Rate of Loading on Jute Fibre-Reinforced Polymer Composite

The environmental consciousness and consumer pressure have forced manufacturing industries to use natural fibres as a substitute for conventional non-renewable reinforcing materials. In the present investigation, the effect of rate of loading on jute fibre-reinforced polymer composite was studied. The mechanical properties (in three-point bend test) like interlaminar shear strength, yield strength and energy at break were examined as a function of strain rate. It was observed that the untreated fibre-reinforced composites were not very sensitive to the rate of loading; however, loading rate sensitivity was observed in alkali-treated fibre-reinforced composites. It has been proposed that fibre pull-out dominates over mechanism of composite failure in alkali-treated condition, and the interlaminar shear strength/yield strength was increased due to the increase in stiffness of the composite with rate of loading (in initial stage); however, at higher strain rate, matrix became susceptible to brittleness as there was lesser time available for crack-blunting to take place. All the microstructures were generated using a scanning electron microscope, and mechanical testing was done using tensile testing machine Instron 1195.

Mechanical and drilling performance of short jute fibre-reinforced polymer biocomposites: statistical approach

In this work, we focus on evaluating the mechanical performance and effects of the drilling parameters as a function of cutting process such as spindle speed (355, 710 and 1400 rev/min), feed rate (50, 108 and 190 mm/min) and the tool diameter (5, 7 and 10 mm) on eventually delamination factors in drilling short jute fibre-reinforced polyester biocomposites (JFRBCs). The work was carried out using Brad & Spur (HSS) drill. The experiment design was established by application of the analysis of variance (ANOVA). The goodness-of-fit for Fd delamination factor was detected between the predicted and experimental results with a high coefficient of R2 of 0.9156 for jute fibre at 5 mm of length reinforced with polyester matrix (J05). The obtained optimum conditions for Fd factor were a feed rate of 50 mm/min, a spindle speed of 1069.41 to 1150.97 rev/min, and a drill diameter of 5 mm.

Compressive and Flexural Strength Improvement of Jute Fibre Reinforced Polymer Composite

Compressive and Flexural Strength Improvement of Jute Fibre Reinforced Polymer Composite

Hybrid filler composition optimization for tensile strength of jute fibre-reinforced polymer composite

In present research work, pultrusion process is used to develop jute fibre-reinforced polyester (GFRP) composite and experiments have been performed on an indigenously developed pultrusion experimental setup. The developed composite consists of natural jute fibre as reinforcement and unsaturated polyester resin as matrix with hybrid filler containing bagasse fibre, carbon black and calcium carbonate (CaCO3). The effect of weight content of bagasse fibre, carbon black and calcium carbonate on tensile strength of pultruded GFRP composite is evaluated and the optimum hybrid filler composition for maximizing the tensile strength is determined. Different compositions of hybrid filler are prepared by mixing three fillers using Taguchi L9 orthogonal array. Fifteen percent of hybrid filler of different composition by weight was mixed in the unsaturated polyester resin matrix. Taguchi L 9 orthogonal array (OA) has been used to plan the experiments and ANOVA is used for analysing tensile strength. A regression model has also been proposed to evaluate the tensile strength of the composite within 7% error by varying the above fillers weight. A confirmation experiment was performed which gives 73.14 MPa tensile strength of pultruded jute fibre polymer composite at the optimum composition of hybrid filler.

Tensile properties of glass/natural jute fibre-reinforced polymer bars for concrete reinforcement

The tensile performance of glass/natural jute fibre-reinforced polymer (FRP) bar, intended for concrete reinforcement was evaluated as a function of volume fraction of natural jute fibre. Natural jute fibre, mixed at a ratio of 7:3 with vinyl ester, was surface-treated with a silane coupling agent and used to replaced glass fibre in the composite in volume fractions of 0%, 30%, 50%, 70%, and 100%. The tensile load-displacement curve showed nearly linear elastic behaviour up to 50% natural jute fibre, but was partially nonlinear at a proportion of 70%. However, the glass/natural jute FRP bars prepared using 100% natural jute fibre showed linear elastic behaviour. Tensile strength decreased as the natural jute fibre volume fraction increased because the tensile strength of natural jute fibre is much lower than that of glass fibre (about 1:8.65). The degree of reduction was not proportional to the natural jute fibre volume fraction due to the low density of natural jute fibre (1/2 that of glass fibre). Thus, as the mix proportion of natural jute fibre increased, the amount (wt%) and number of fibres used also increased.

Behavior of sisal fiber concrete cylinders externally wrapped with jute FRP

The use of environmentally friendly natural fibers as building materials is benefit to achieve a sustainable construction. This article performs a study on the use of natural jute fibers as reinforcement of concrete and natural sisal fibers in fiber reinforced polymer (FRP) composites as concrete confinement, i.e. sisal fiber reinforced concrete (SFRC) composite column wrapped by jute FRP (JFRP) (SFRC-JFRP). Uniaxial compression test was conducted to assess the compression performance of the composite columns as axial structural member. A total of 24 specimens were tested. The effects of JFRP wrapping thickness and sisal fiber inclusion on the compressive performance of the composite columns were investigated. Results indicate that JFRP confinement significantly increases the compressive strength and ductility of both PC and SFRC with an increase in JFRP thickness. Besides, the inclusion of sisal fiber further enhances the strength as well as the efficiency of confinement under uniaxial compression. Also, the models for ultimate strength and ultimate strain of PC-JFRP and SFRC-JFRP are proposed. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers