Number Of Fabric Layers Research Articles

The effects of metal type, number of layers, and hybrid yarn placement on the absorption and reflection properties in electromagnetic shielding of woven fabrics

In this study, stainless steel, copper, and silver wires were intermingled with two polyamide 6.6 filaments through the commingling technique to produce three-component hybrid yarns. The produced hybrid yarns were used as weft in the structure of plain woven fabric samples. The electromagnetic shielding effectiveness parameters of samples were measured in the frequency range of 0.8–5.2 GHz by the free space technique. The effects of metal hybrid yarn placement, number of fabric layers, metal types, and wave polarization on the electromagnetic shielding effectiveness and absorption and reflection properties of the woven fabrics were analyzed statistically at low and high frequencies separately. As a result, the samples have no shielding property in the warp direction. Metal types show no statistically significant effect on electromagnetic shielding effectiveness. However, fabrics containing stainless steel have a higher absorption power ratio than copper and silver samples. Double-layer samples have higher electromagnetic shielding effectiveness values than single-layer fabrics in both frequency ranges. However, the number of layers does not have a significant effect on the absorbed and reflected power in the range of 0.8–2.6 GHz. There was a significant difference above 2.6 GHz frequency for absorbed power ratio. An increase in the density of hybrid yarns in the fabric structure leads to an increase in the electromagnetic shielding effectiveness values. Two-metal placement has a higher absorbed power than the full and one-metal placements, respectively. The samples which have double layers and including metal wire were in their all wefts reached the maximum electromagnetic shielding effectiveness values for stainless steel (78.70 dB), copper (72.69 dB), and silver composite (57.50 dB) fabrics.

Interface pressure generated by knitted fabrics of different direction, composition and number of layers in sport compression garments

The present study aimed to determine the effect of fabric direction, fabric composition and number of fabric layers on pressure generated by sport compression garments. Experimental fabric used in commercially available compression sport garments was chosen. Experimental fabric sleeves imitating a part of a pressure garment were assembled and placed on cylinders of different diameters, so that they provided different fabric direction, fabric composition of sleeve and number of layers in assemblies along the circumference of the cylinders. A Salzmann MST MK IV pressure-measuring device and Salzmann MST 2007 software were used to measure the interface pressure generated by the sleeves. It was established that different direction, fabric composition of sleeve and number of fabric layers in fabric assemblies influences the interface pressure.

Low cost drinking water treatment using nonwoven engineered and woven cloth fabrics.

The study investigated two engineered fabrics and five cloth fabrics for low cost drinking water treatment. An optimized fabric filtration method has been developed and tested. Numerical models for predicting particulate removal efficiency have been developed for each fabric as support tools for selecting optimal process configuration. Both engineered fabrics showed better performance and achieved the most effective particulate removal for the highest number of layers used. Sequential filtration was done on eight layers for representative fabrics of each type and recorded higher contaminant removal than one filtration run. Geotextile 1 was better than geotextile 2 in particulate removal and recorded Escherichia coli removals of up to 1.4 log removal value (LRV) for eight-layer normal filtration and 3.0 LRV for four-pot sequential filtration. Brushed cotton was best among the cloth fabrics in particulate removal but performed below expectation in bacterial removal. It recorded E. coli removals of only 0.04 LRV and 0.2 LRV for eight-layer normal filtration and four-pot sequential filtration, respectively. Effluent turbidity decreased exponentially with number of fabric layers, in line with porous media filtration theory. The optimized filtration method produced very clear drinking water of relatively safe quality using geotextile 1. Appropriate disinfection is still recommended to ensure continued water safety.

Development and characterization of three-dimensional woven fabric for ultra violet protection

PurposeThe purpose of this paper is to investigate the effect of materials, three dimensional (3D) structure and number of fabric layers on ultraviolet protection factor (UPF), air permeability and thickness of fabrics.Design/methodology/approachTotal 24 fabrics samples were developed using two 3D structures and two weft materials. In warp direction cotton (CT) yarn and in weft direction polypropylene (PP) and polyester (PET) were used. Air permeability, thickness and UPF testings were performed and relationship among fabric layers, air permeability, thickness and UPF was developed.FindingsUPF and thickness of fabrics increases with number of fabric layers, whereas air permeability decreases with the increase in number of fabric layers. Furthermore, change of multilayer structure from angle interlock to orthogonal interlock having same base weave does not give significant effect on UPF. However, change of material from polyester (PET) to polypropylene (PP) has a dominant effect on UPF. Minimum of three layers of cotton/polyester fabric, without any aid of ultraviolet radiation (UV) resistant coating, are required to achieve good. Cotton/polyester fabrics are more appropriate for outdoor application due to their long-term resistance with sunlight exposure.Originality/valueLong-term exposure to UV is detrimental. So, there is need of proper selection of material and fabric to achieve ultraviolet protection. 3D fabrics have yarns in X, Y as well as in Z directions which provide better ultraviolet protection as compared to two dimensional (2D) fabrics. In literature, mostly work was done on ultraviolet protection of 2D fabrics and surface coating of fabrics. There is limited work found on UPF of 3D woven fabrics.

Influence of pre-tension on ballistic impact performance of multi-layer Kevlar 49 woven fabrics for gas turbine engine containment systems

In this paper, ballistic impact tests on wrapped multi-layer Kevlar 49 woven fabric systems were carried out with a flat blade projectile to investigate the impact response during a fan blade out event. The influences of the number of Kevlar layers and pre-tension were discussed particularly. Test results were used to analyze failure modes and energy absorption characteristics of multi-ply Kevlar fabrics. Results show that there are two kinds of impact damage for fabrics: global deformation mainly involving stretching of yarns in the impact region and fabric wrinkle from both sides to the impact zone, and local damage characterized by yarn fracture, yarn pull-out, and yarn unraveling. The energy absorption capability of Kevlar 49 woven fabrics improves with the number of fabric layers. The energy absorbed by multi-layer fabrics increases slightly at the beginning and then decreases substantially with pre-tension. The work in this paper can provide guidance for designing light-weight multi-layer fabrics containment systems.

Flexural Behavior of RC Slabs Strengthened in Flexure with Basalt Fabric‐Reinforced Cementitious Matrix

This paper presents both experimental and analytical research results for predicting the flexural capacity of reinforced concrete (RC) slabs strengthened in flexure with basalt fabric‐reinforced cementitious matrix (FRCM). A total of 13 specimens were fabricated to evaluate the flexural behavior of RC slabs strengthened with basalt FRCM composite and were tested under four‐point loading. The fiber type, tensile reinforcement ratio, and the number of fabric layers were chosen as experimental variables. The maximum load of FRCM‐strengthened specimens increased from 11.2% to 98.2% relative to the reference specimens. The energy ratio and ductility of the FRCM‐strengthened specimens decreased with the higher amount of fabric and tensile reinforcement. The effective stress level of FRCM fabric can be accurately predicted by a bond strength of ACI 549 and Jung’s model.

Shear strengthening of concrete members with TRM jackets: Effect of shear span-to-depth ratio, material and amount of external reinforcement

Abstract An experimental work on reinforced concrete (RC) rectangular beams strengthened in shear with textile reinforced mortar (TRM) jackets is presented in this paper, with focus on the following investigated parameters: (a) the amount of external TRM reinforcement ratio, ρf, by means of using different number of textile layers and different types of textile fibre materials (carbon, glass, basalt); (b) the textile geometry, and (c) the shear span-to-depth ratio, a/d. In total, 22 tests were conducted on simply supported rectangular RC beams under (three-point bending) monotonic loading. The experimental results revealed that: (1) TRM is very effective when the failure is attributed to debonding of the TRM jacket from the concrete substrate; (2) the trend of effective strains for carbon, glass and basalt TRM jackets is descending for increasing values of the TRM reinforcement ratio, ρf, when failure is associated to debonding of the jacket; (3) the effect of textile geometry is significant only for low values of ρf, resulting in variances in the capacity enhancement and the failure modes, and (4) the shear span-to-depth ratio has practically no effect to the failure mode nor to the TRM jacket contribution to the total shear resistance of the RC beams.

Study of aperture size and its aspect ratio of conductive hybrid yarn woven fabric on electromagnetic shielding effectiveness

The influence of aperture aspect ratio and its size on shielding effectiveness of grid fabric made up of carbon and stainless steel (SS) has been investigated in this article. The carbon and stainless steel based hybrid yarn was prepared by direct twisting machine and a woven grid fabric was prepared from the hybrid yarn by using CCI sample loom with varying warp and weft densities. The fabric samples were analyzed for shielding effectiveness (SE) in low frequency range (50 MHz to 1.5 GHz) using coaxial transmission line holder and a vector network analyzer. It has been observed that conductive hybrid yarns placed in one direction of the fabric showed polarization effect with the resonance peak at 0.65 GHz. The grid fabric having conductive yarns in both the directions showed larger attenuation than the unidirectional (UD) grid fabric. In addition, fabric made-up of carbon filaments showed higher attenuation level than that of SS filaments due to its larger conductivity. When the both carbon and stainless steel are introduced as hybrid yarn in the fabric, a maximum SE was observed. In addition, effect of orientation of fabric layers on SE has been investigated. The increase in number of fabric layers increased the SE to a certain frequency. The carbon UD fabrics with 0°/45° (or) 0°/45°/90° showed larger SE than the fabrics with other orientation angles. The similar behavior was observed for SS UD fabrics. The developed fabrics can be used as polarization attenuator, shielding mesh, etc.

Effect on Piercing Resistance of Treating Ballistic Fabrics with Resin in Ethanol

The piercing resistance of ballistic fabrics was studied as a function of both the resin concentration in EtOH solutions and the number of fabric layers.

Experimental study on basalt textile reinforced concrete under uniaxial tensile loading

This study focuses on 24 experimental cases to investigate the influences of textile layers, prestress levels and short steel fibers on the tensile behavior of basalt textile reinforced concrete (TRC). The tensile behavior of basalt TRC is considerably influenced by the number of textile layers. The TRC specimens with one or two textile layers demonstrate no reinforcement efficiency, whereas those arranged with three to five textile layers exhibit pronounced strain-hardening behavior and consequently, prominent enhancement of tensile behavior and optimized cracking patterns. For the prestressed TRC specimens, evident increases in first-crack stress are observed with increasing prestress levels, whereas only a slight influence on ultimate tensile strength can be achieved. Moreover, maintaining the value of the prestress within an appropriate level is an important issue for TRC. Furthermore, the TRC specimens with an appropriate prestress level exhibit increasingly favorable tensile response with the rising volume fraction of short steel fibers.

Filtration properties of carbon woven fabric filters supplied with high voltage for removal of PM 1.0 particles

Abstract Electrostatic precipitation is combined with a carbon fabric filter to develop a novel filtration system with high collection efficiency for submicron particles while maintaining a pressure drop as low as 6–56 Pa. The effects of high voltages on the filtration properties of carbon woven fabric filters are investigated by varying the fabric areal density, face velocity, number of fabric layers, and environmental relative humidity (RH). The filtration performance tests show that the corona initiation voltage applied to carbon woven fabric should be higher than 20 kV in ambient condition, and filtration efficiency increases with the increasing of fabric areal density and supplied voltage. As the face velocity increases from 2 m/min to 4 m/min, the filtration efficiency at 30 and 40 kV decreases 13%. As the face velocity increases from 4 to 8 m/min, the filtration efficiency decreases much less. The filtration efficiency is not significantly influenced by the number of fabric layers but can be increased dramatically with the increasing of RH. The maximum filtration efficiency reaches 99.8% for PM 1.0 at high RH. Meanwhile, the corona inception voltage decreases to 10 kV as the RH increased from 40% to 95%.

Identification of Seam Performance of Natural Wool Textile Fabrics

Wool is a natural animal fibers spun from the fleece of sheep. To sew a wool fabric garment, play the seam performance the first role in judgment the quality of the garment, since the wool fabrics had special Characteristics. The purpose of this study is to identify the seam quality throughout determining the seam strength, seam elongation, seam efficiency and seam stiffness. For the design of experiments, three wool textile fabrics (light, medium and heavy) are chosen and sewn with different sewing factors. Three seam types (SSa-1, LSq and SSw), they differ in the number of fabric layers in the seam area. Three stitch length (1.5 mm, 3 mm and 4.5 mm) and three level of stitch rows (1 row, 2 rows and 3 rows). Results indicated that for all investigated materials and sewing factors recorded the lapped seam type SSw the highest values of the seam strength, seam elongation, seam performance and seam stiffness, followed by the lapped seam type LSq and the superimposed seam SSa-1). The stitch density, in the form of the stitch length, had a significant positive effect on the four studied seam properties (strength, elongation, efficiency and stiffness). In addition showed the number of stitch rows also a hug effect in changing the seam performance of the wool textiles fabrics.

Effect of Fabric Cover and Pore Area Distribution of Carbon/Stainless Steel/Polypropylene Hybrid Yarn-Woven Fabric on Electromagnetic Shielding Effectiveness

The electromagnetic shielding behavior of fabrics woven with carbon/stainless steel/polypropylene (C/SS/PP) hybrid yarns were investigated in the frequency range of 300 kHz to 1.5 GHz. This study mainly emphasizes the electromagnetic shielding behavior of C/SS/PP hybrid yarn fabric and the effect of different fabric parameters such as pick density, fabric architecture and number of fabric layers on shielding effectiveness (SE) of fabrics with C/SS/PP hybrid yarns. The SE of fabric samples were tested by a vector network analyzer using a coaxial transmission line tester. In addition, surface images of different fabric structures were examined to appreciate the effect of yarn floats on the shielding behavior of fabrics. From the SE test, it was observed that an increase in pick density increases the SE of C/SS/PP hybrid yarn fabric due to addition of carbon and SS content in the fabric. Besides, the fabric cover and pore area distribution are also changed for varying pick densities. Essentially, a fabric’s architecture plays an important role in the fabric cover and pore area distribution. The one-end float (1/1 plain) fabric of 6.3 ppcm provides higher shielding of 88.44 dB than a 4-end (4/1 twill) or 7-end float (8-end satin) fabrics of 6.3 ppcm. Moreover, an increase in the number of fabric layers also improves the SE of fabrics. The developed C/SS/PP hybrid yarn fabric can be used for shielding wireless transmissions, radar transmissions and for shielding panels.

Behaviour of tunnel lining strengthened by textile-reinforced concrete

In this paper, the effectiveness of textile-reinforced concrete (TRC), as a means of increasing the bending resistance of tunnel lining, was experimentally and analytically investigated. The short RC column strengthened by TRC on the side farthest from the axial load was designed to investigate the behaviour of tunnel lining strengthened by TRC. The parameters under study included the loading eccentricities, the number of textile layers and the preload ratio of the short RC columns. The experimental programme was composed of two control RC columns with different eccentricities. Five RC columns which were externally upgraded by TRC sheets were also analysed for their enhanced flexural capacity. Experimental responses of the reinforced concrete members strengthened in bending indicated that TRC substantially enhanced the bending resistance. Specifically, the gain increased with a concurrent increase in both the number of layers and eccentricity. The gain greatly worsened, however, with an increase in the preload ratio. An analytical method considering the non-linear behaviour of the materials was also proposed and validated through the test results. The study was extended analytically to include additional cases of TRC-strengthened specimens with some more parameters, including different concrete and steel types.

The Prediction of Needle Penetration Force in Woven Denim Fabrics Using Soft Computing Models

The aim of this paper was to predict the needle penetration force in denim fabrics based on sewing parameters by using the fuzzy logic (FL) model. Moreover, the performance of fuzzy logic model is compared with that of the artificial neural network (ANN) model. The needle penetration force was measured on the Instron tensile tester. In order to plan the fuzzy logic model, the sewing needle size, number of fabric layers and fabric weight were taken into account as input parameters. The output parameter is needle penetration force. In addition, the same parameters and data are used in artificial neural network model. The results indicate that the needle penetration force can be predicted in terms of sewing parameters by using the fuzzy logic model. The difference between performance of fuzzy logic and neural network models is not meaningful ( RFL=0.971 and RANN=0.982). It is concluded that soft computing models such as fuzzy logic and artificial neural network can be utilized to forecast the needle penetration force in denim fabrics. Using the fuzzy logic model for predicting the needle penetration force in denim fabrics can help the garment manufacturer to acquire better knowledge about the sewing process. As a result, the sewing process may be improved, and also the quality of denim apparel increased.

Research into fabrics used in compression therapy and assessment of their impact on treatment regimens.

The objective of this paper is to provide a definition for interface compression that uses essential principles of engineering science. This definition discusses factors that influence the amount of applied pressure, including the size of the limb, the amount of fabric tension (graduated pressure profile), the number of layers, and the material creep characteristics. Laplace's law has been applied to compression therapy. Tension-extension profiles have been derived for different types of compression fabric to demonstrate the effects of resistance and friction. Force-time profiles have been derived for different types of fabric compression systems to demonstrate the effects of creep (creep is defined generally as the irreversible deformation of a material over time in the presence of a constantly applied load). Here, the fabric compression systems were applied to a test-bed that supplied a constant force to the fabric; creep was taken as the loss of compression (pressure) over time. Laplace's law has been interpreted for compression therapy. The amount of fabric tension is determined by the extent to which it is stretched during application, as well as by changes in the size of the limb. The fabric's relative elasticity, which is quantified by the rigidity index and is related to the slope of the tension-extension profile, dictates the amount that the applied force changes with extension. Compression systems that use multiple layers of fabric are generally more resistive to stretching than single-layer systems. Friction acting between the layers, as well as the added force from each layer, serves to increase the overall compression of these systems. As the applied force rises, the amount of pressure supplied by the fabric increases. However, when the same force (or fabric extension) is used, the applied pressure is less when distributed over a larger surface area. In other words, as the circumference of the limb increases, the pressure decreases. This is the driving principle behind graduated compression. In addition to the changes in fabric tension resulting from extension, the creep characteristics of the material affect the amount of compression provided throughout the wear cycle. The factors influencing interface compression are multi-faceted. Based upon the interpretation of the material properties of compression fabrics (tension-extension profile, number of fabric layers, and creep), new therapeutic guidelines have been established, and others clarified. This study was sponsored by Carolon. L. Reid, and S. Kravitz are employees of Carolon and E. Grant is a Member of the Board. M. Hegarty-Craver and C. Kwon have received monetary compensation as researchers for Carolon.

Evaluation of Woven Denim Fabric Sewability based on Needle Penetration Force

This paper investigates the sewability of the woven denim fabrics based on needle penetration force (NPF). For this purpose, the effects of fabric weight, number of fabric layers, needle size, and the interaction effect of these parameters on NPF in twill denim fabrics were investigated. In addition, the influence of weave pattern on NPF was studied. The statistical analysis results show that NPF is influenced by these parameters. Fabric weight has a greater effect on NPF than other parameters. With increasing fabric weight, number of fabric layers, and needle size, the NPF increases. The trend of this increase is nonlinear as predicted by a cubic regression equation. The fabric sewability is also influenced by the mentioned parameters. The fabric sewability becomes poor with increasing fabric weight, needle size, and number of fabric layers. Generally, lighter fabrics sewn with finer needles have better sewability.

Electromagnetic interference shielding effectiveness of SS/PET hybrid yarn incorporated woven fabrics

A detailed study of electromagnetic shielding effectiveness (EMSE) of woven fabrics made of polyester and stainless steel/polyester blended conductive yarn was presented in this research work. Fabrics with different structures were analyzed and their shielding behavior was reported under different frequencies. Shielding efficiency of fabric was analyzed by vector network analyzer in the frequency range of 300 kHz to 1.5 GHz using coaxial transmission line holder. The effects of different fabric parameters such as weft density, proportion of conductive weft yarn, proportion of stainless steel content, grid openness, weave pattern and number of fabric layers on EMSE of fabrics were studied. The EMSE of fabric was found to be increased with increase in proportion of conductive yarn in the weft way. With increase in overall stainless-steel content in the fabric, the EMSE of fabric was increased. As such weave is considered, it did not have significant effect on EMSE of fabrics. But fabric with lower openness and aperture ratio showed better conducting network, hence better shielding. With increase in number of layers of fabric and ply yarns, EMSE of fabric was increased.

Modeling of needle penetration force in denim fabric

Purpose – This paper aims to predict the needle penetration force (NPF) in denim fabrics using the artificial neural network (ANN) and multiple linear regression (MLR) models based on the effects of various sewing parameters. Design/methodology/approach – In order to design the ANN and MLR models, four parameters including fabric weight, number of fabric layers, weave pattern, and sewing needle size are taken into account as the input parameters and NPF as the output parameter. According to these parameters, 140 samples of data were resulted. Each sample was tested five times. From these 140 data (input-output data pairs), 112 were used for training the ANN and MLR models and 28 samples were used to test the performance of ANN and MLR. Also, the NPF was measured on the Instron tensile tester to simulate sewing process. Findings – The results indicated that the NPF in denim fabrics can be well predicted in terms of sewing parameters by using ANN and MLR models, in which the ANN model exhibits greater performance than MLR (RANN=0.989> RMLR=0.901). Research limitations/implications – The NPF measurement method is limited at low speed. Originality/value – Using the ANN model for forecasting NPF in denim fabrics can help the garment manufactures to produce high-quality denim products and improve the sewing process through reducing seam damage. The NPF could be also measured in the cycle loading conditions similar to sewing machine process by using a special designed tools mounted on the Instron tensile tester.

Special Nylon Fabric as a New Material for Reinforcing Cement Composite

Textile reinforced concrete (TRC) is a new composite material in structural engineering, in which textile fabrics are used as reinforcement. In recent years, much research has been done to investigate the bending behavior of TRC samples. The focus of this research is on the use of low performance yarns as reinforcement and investigating the effect of finesse of yarns and reinforcement ratio on the bending behavior of TRC samples. The comparison of samples strengthened with same number of fabric layers but made up different finesses show that ultimate strength of samples increases in the yarns with lower finesse. Meanwhile the results show that reinforcement ratio is an important factor on bending behavior of TRC samples and strain hardening behavior can be obtained in 1/15% of reinforcement ratio in coarser yarns.