Ordinary Fiber Research Articles

Investigating the Characteristics of Engineering Properties of Concrete Made from Hormak River Sediments and Sistan Reed Fibers

The purpose of this research is to investigate the characteristics of engineering properties of concrete made from Hormak river sediments and Sistan reed fibers.in order to investigate the effect of reed fibers on the engineering properties of concrete, the ratio of water to cement in all designs is constant and equal to 195 to 410 and experiments have been performed on 5 samples containing fibers and without fibers, before determining the optimal amount of each From the mentioned fibers to strengthen the concrete, the results of the necessary tests on fresh and hardened concrete were examined. In this study, in addition to mixing reed fibers with concrete, laboratory methods such as Compressive and tensile strength were used to confirm the accuracy of the results and the importance of selecting suitable materials at low cost in a short time before the concrete mixing project. The results show that the addition of reed fibers to concrete has increased the compressive strength in concrete samples Comparing the results of this test in ordinary concrete and fiber reinforced concrete, showed that this increase in strength at the ages of 7 to 28 days has increased only in samples S2 and S3 and is Similar to the typical concrete example isS1, While in S4 and S5 samples, which were samples of three-row fibers, there is a large decrease in compressive strength. Adding reed fibers initially increases the compressive and tensile strengths, but over time reduces these resistances. DOI: https://doi.org/10.52783/pst.789

Single-frequency erbium-doped fiber laser based on self-injection feedback

In this paper, a single-frequency erbium-doped fiber laser based on self-injection feedback is reported, which uses a high-reflectivity broadband fiber Bragg grating, an ordinary commercial high-doped erbium fiber and a low-reflectivity broadband fiber Bragg grating to form the main resonant cavity, and a stable narrow linewidth single-frequency laser output is achieved by connecting a single-mode fiber and a low reflectivity narrowband fiber Bragg grating to form self-injection feedback. Then, a saturated double-pass erbium-doped fiber amplifier and a saturable absorber were added to the self-injection optical path, which well suppressed the relative intensity noise and phase noise and the relaxation oscillation intensity was well suppressed by about 18.08 dB, and the phase noise was 36.7dBc·Hz−1 suppression, the edge-mode rejection ratio is increased by 13 dB, and the final laser linewidth is about 270 Hz, and the output power is 8.5 dBm.

EFFICIENCY OF USING FIBER CONCRETE AS CORE FOR STEEL CONCRETE COLUMNS OF SQUARE CROSS SECTION

The article examines the effectiveness of using fiber concrete as a core for reinforced concrete columns with a square cross-section. For this, at the first stage, the calculation of a steel-concrete column with dimensions of 100×100×3 mm, length of 500 mm was carried out using as a core a cross-section of concrete grade C20/25. At the next stage of the research, based on the conditions of the same bearing capacity of the columns, cross-sections were selected using fiber concrete with steel and basalt fibers at different values of the thickness of the steel shell. Steel fiber "Chilyabinka" was used, which was introduced at the rate of 32,536 kg/m3 of concrete. Basalt fiber was used with a length of 12 mm, and was added in the amount of 0.2% of the mass of cement. The dependence of the area of the concrete core and the area of the steel shell on the thickness of the steel shell is plotted. A comparison of the cost and characteristics of reinforced concrete columns with the use of ordinary concrete and fiber concrete with two types of fibers as a core cross-section was also carried out: steel and basalt. Based on research, the following conclusions can be drawn that the use of fiber concrete as the core of a steel concrete column of rectangular cross-section significantly improves a number of characteristics. Thus, with the same bearing capacity and thickness of the shell, the cost of a column with a core made of steel fiber concrete is reduced by 15%, weight by 26%, cross-sectional size by 13% compared to concrete without fiber. The cost of a column with a core made of basalt fiber concrete is reduced by 12%, weight by 21%, cross-sectional size by 9% compared to concrete without fiber. By changing the thickness of the steel shell, you can also influence the characteristics of the column, in particular, reduce the cross-sectional dimensions and weight. But at the same time, the cost of the column increases. Keywords: fiber concrete, steel concrete, column, bearing capacity

Generation of sub-150 fs, 10 W-class, pedestal-free 2.07 µm ultrashort pulses using a cascade compression system.

We report high-power pedestal-free ultrashort pulses in a cascade compression system. In the self-compression stage, the 2 µm ultrashort pulses with 123 fs duration and up to 21.7 W output power were obtained in a 0.3 m 50 µm core diameter fiber. It is the highest self-compressing power ever obtained in a silica fiber with an all-fiber 2 µm laser amplifier as the pump source. To obtain purer pedestal-eliminated pulses, we further increase the fiber length to 1 m to trigger the soliton self-frequency shifting (SSFS) effect. By employing an enhanced SSFS technique based on third-order dispersion (TOD) and filtering out the unshifted signal light, we finally achieved sub-150 fs, 10 W-class, 1.2-MW peak-power, pedestal-free 2.07 µm ultrashort pulses. This is also the highest, to the best of our knowledge, power and energy of Raman soliton obtained by SSFS in an ordinary silica fiber.

Progressive Collapse Behavior of a Precast Reinforced Concrete Frame System with Layered Beams

A possible way to improve the structural safety and robustness of precast building structures is to develop effective precast frame systems with layered beams, which combine prefabricated parts with cast-in situ ordinary concrete, high-performance concrete, fiber concrete, or FRP. The paper provides a new type of precast reinforced concrete frame system with layered beams for rapidly erected multi-story buildings resistant to accidental actions. Using a combination of the variational method and two-level design schemes, a simplified analytical model has been developed for structural analysis of the precast reinforced concrete frame system, both for serviceable and ultimate limit states as well as for accidental actions. The proposed model allows for determining shear deformations and the formation and opening of longitudinal cracks in the intermediate contact zone between precast and monolithic parts of reinforced concrete structural elements of the frame, as well as the formation and opening of normal cracks because of the action of axial tensile force or bending moment in these elements. The design model was validated by comparing the calculated and experimental data obtained from testing scaled models of the precast reinforced concrete frame system with layered beams. The paper investigates and thoroughly analyzes the factors affecting the stiffness and bearing capacity of the intermediate contact zone, discusses the criteria for the formation of shear cracks along the contact zone of precast and monolithic concrete, and examines the change in the stiffness and dissipative properties of layered elements at different stages of their static–dynamic loading. The robustness of the experimental models of the structural system was not ensured under the specified load, section dimensions, and reinforcement scheme. Following an accidental action, longitudinal cracks were observed in the contact joint between the monolithic and prefabricated parts in the layered beams. This occurred almost simultaneously with the opening of normal cracks in adjacent sections. A comprehensive analysis of the results indicated a satisfactory degree of agreement between the proposed semi-analytical model and the test data.

Mechanical properties of basalt fiber/ epoxy resin composites

This paper presents a study regarding the obtaining, characterizing and mechanically testing a new laminar composite material, consisting of epoxy resin reinforced with basalt plain fabric. The composites were obtained by manual lay-up, cross-link stage being developed by pressure molding in a hydraulic press. Rectangular plates were obtained and cut into samples with specific shapes, for the mechanical tests (tensile, three-point bending and compression). After testing, the fracture zone was analyzed using optical microscopy to observe the behavior of the composite following the mechanical stresses applied (fracture mechanism, voids presence and fiber delamination identification). Due to the low costs and non-hazardous nature, basalt fibers can be a serious competitor in the production of laminar composites that could successfully replace ordinary glass fiber composites. The mechanical properties in tensile, three-point bending, and compression of epoxy-resin-impregnated basalt fiber composites are comparable and even exceed those of widely used epoxy-resin-impregnated fiberglass composites.

Non-destructive strategy to extract sustainable helix and high-strength Musa core fibers for rapid water conduction and evaporation

The reuse and development of natural waste resources is a hotspots and challenges in the research of new fiber materials and the resolution of environmental concern globally. Herein, this study aimed to develop a simple and direct manual extraction process to extract Musa core fibers (MCFs) for rapid water conduction and evaporation. Through simple processes such as ring cutting and stretching, this green and non-destructive inside-out extraction strategy enabled Musa fibers to be naturally and harmlessly degummed from natural Musa stems, with good maintenance of the fiber structure and highly helical morphology. The extracted fibers are composed of regularly and closely arranged cellulose nanofibrils in the shape of ribbon spirally arranged multi-filaments, and the single filament is about 2.65 μm. The high-purity fibers exhibit ultra-high tensile strength under a non-destructive extraction process, and the ultimate tensile strength in dry state is as high as 742.95 MPa. The tensile strength is affected by the number of fiber bundles, which shows that tensile strength and tensile modulus is higher than those of vascular bundle fibers in dry or wet condition. In addition, the MCFs membrane indicates good water conductivity, with a water absorption height of 50 mm for the sample in only 60 s. Moreover, the water evaporation rate of MCFs reaches 1.37 kg m−2 h−1 in 30 min, which shows that MCFs have excellent water conductivity and evaporation rate compared with ordinary cotton fibers. These results indicate that MCFs have great potential in replacing the use of chemical methods to extract fibers from vascular bundles, providing an effective way to achieve sustainability in quick-drying applications, as well as in the sustainable development of natural waste resources.

Analisis Gangguan Transmisi Fiber Cut dan Pengembangan Solusi untuk Meningkatkan Availability Sistem Komunikasi Fiber Optik Section Banua Hanyar – Bati Bati

Technology continues to develop very quickly, especially long-distance communication and transmission technology. This is due to the increasing human need for the internet, as seen by its availability. The main objective of this research is to analyze the impact and solution to Fiber Cut transmission on availability in the Banua Hanyar - Bati Bati Section. This research uses a correlative descriptive quantitative method to obtain a solution, namely replacing ordinary fiber optic cables and many existing cable with a new anti-rodent fiber optic cable 3 km long located 0.8 km to 3.8 km from Banua Hanyar. This solution is said to be very influential because it succeeded in increasing the availability of the Banua Hanyar - Bati Bati Section system to 100%.

Numerical Analysis of Hybrid Fibre-Reinforced Concrete Beam-Column Joint

Beam-column joint is the most vulnerable location of a moment-resisting reinforced concrete frame structure. The joint region experiences the maximum shear stress both in vertically and horizontally which is generated due to the shear transfer mechanism from the adjoining beams and columns. The shear capacity and bond stress capacity are the two major factors affecting the strength of a joint core in RC structure. An important discovery recently is the ductile behaviour of the whole structure under repeated loading. The behaviour of the concrete beyond elastic limit which is in the concrete hardening zone can drastically influence the ductility of the concrete. The non-linear stress-strain behaviour after the onset of the initial crack and up to ultimate compressive strength plays an important role in improving ductility. Beyond the ultimate compressive strength, concrete will undergo softening which is neglected in this study as once concrete reaches ultimate stress it is unsafe for service. This material ductility can be fulfilled with the application of high-strength fibres with ductile behaviour. However, the hybridization of two or more fibres can incorporate two different characteristics of the fibre used. The use of ordinary-grade of concrete moreover reduces the shear-resisting capacity of the joint. A hybrid mix of hooked-end steel fibre with basalt fibre and crimpled steel fibre with polypropylene fibre are used with a volume fraction of 1% to 1.4% of the concrete. In this study, ordinary M25 grade concrete and fibre mixed M25 grade concrete is employed under static and cyclic loading. The laboratory tests are also conducted to evaluate the compressive strength, split-tensile strength, and flexural strength of the hybrid mix fibre-reinforced concrete at the age of 28th days. Five full-scale models of the beam-column joint are designed as per the Bureau of Indian Standards. Numerical models of concrete and steel reinforcement are developed. Numerical analysis is carried out using finite element software ANSYS-v21. The behaviours of the beam-column joint are observed under static as well as cyclic loading. Crack patterns, first crack load, initial displacement, ultimate load, and ultimate displacement are observed under static conditions. And under cyclic loading, hysteresis load vs displacement, energy dissipation, and stiffness degradation are observed. The hybridization of hooked steel with basalt fibre gives better results in mechanical strengths and the hybrid effect of crimpled steel with polypropylene fibre gives better results in mechanical strengths. And also under numerical study, the above specimens show an improvement in energy dissipation capacity. Keywords beam-column joint, hybrid fibre reinforced concrete, numerical concrete model, ANSYS, static, reverse cyclic, energy dissipation, stiffness, crack

Optimization of the Shape of Hooked-End Steel Fiber Based on Pulling Out and Reinforcing Cementitious Composites.

Efficient steel fiber-reinforced cementitious composites (SFRCC) should improve not only the ultimate tensile strength but also the residual tensile strength (post-cracking tensile strength) of the SFRCC matrix. The degradation of the post-cracking tensile strength of SFRCC depends on the pullout properties of the steel fibers from the cementitious matrix. When the straight steel fiber was pulled out from the matrix, the pullout resistance was affected by the actions of bonding and friction. After debonding, the load was transferred only by friction, and the pullout resistance decreased rapidly, resulting in a weak reinforcing effect. In addition, changing the fiber shape can effectively slow down the decreasing rate of the pullout resistance of the steel fibers, thus improving their reinforcing effects. In this study, the shape of the steel fibers was optimized to slow down the decrease in the pullout resistance of the steel fibers from the cementitious matrix, thus achieving better tensile properties of SFRCC. First, a calculation model for the steel fiber pullout resistance was established. On this basis, a method to optimize the shape of the steel fibers was proposed. Finally, the pulling out behavior of steel fibers with different end hook shapes was tested, and the influence of the steel fiber shape on the decreasing rate of the residual pullout resistance was analyzed. The results showed that the optimized hooked-end steel fibers had better pullout resistance than ordinary hooked end steel fibers of the same diameter, tensile strength, and matrix.

Regression Anaylsis for the Experimental Study on the Pullout Strength of Steel Fiber Self- Compacting Concrete

This article describes experimental research of the interfacial adhesion of triple blended steel fibre self-compacting concrete (TBSFSCC) and it varies depending on the percentage of steel fibre. In self-compacting concrete, mineral admixtures such as condensed silica fume and flyash are utilised as supplementary cementitious materials (SCMs).the percentage of replacement of cement by condensed silica fume at 10 where as flyash at 20 respectively, to meet the SCC criteria stipulated by ACI. The embedment length of a steel bar with a diameter of 12mm was chosen to be 100mm in all of the standard specimens. Fe-415 steel rod is used in this research. The pull-out test in the universal testing machine is used to evaluate the bond strength of this triple blended Self-Compacting Concrete (TBSCC). Ordinary steel fibres are then added to the concrete volume at various percentages, such as 0.2, 0.4, 0.6, and 0.8. The bond strength, slip, and the method of failure of each rebar were all noted in the test results. The comparison of these results clearly shows that the percentage of steel fibre contributes to the TBSCC bond strength, and conclusions are generated.

Recent development of innovative steel fibers for ultra-high-performance concrete (UHPC): A critical review

This paper presents a comprehensive review of recent advancements in innovative high-strength steel fibers for ultra-high-performance concrete (UHPC). Firstly, commercially available ordinary steel fibers for UHPC products are introduced, and the analysis of fiber aspect ratio on the mechanical properties of UHPC follows. Subsequently, the historical development of deformed steel fibers, including hooked, corrugated, twisted, half-hooked, and curvilinear steel fibers for UHPC, is reviewed, accompanied by a discussion of their impact on various properties of UHPC. In response to limitations associated with specific deformed steel fibers in UHPC due to stress concentration, recent development of surface-refined straight steel fibers is presented. The paper further highlights the development of surface-roughened steel fibers through physical and chemical methods aimed at increasing surface roughness and interfacial friction in UHPC, along with an explanation of the benefits of these surface-roughened steel fibers in enhancing both fiber-matrix interfacial bond and tensile performance. Additionally, the adoption of active and inert nanomaterial-based surface coatings on steel fibers for UHPC is explored to intensively reinforce the interfacial transition zone between the fiber and matrix. Hybrid surface refining methods and various chemical treatment techniques for modifying the surface properties of steel fibers in UHPC are reviewed and discussed. Finally, based on the available current database, optimal fiber types as reinforcements for UHPC, in terms of tensile and flexural performances, are suggested.

Single-longitudinal-mode narrow linewidth broadband tunable Brillouin random laser including dispersion compensation fibers

We propose and demonstrate a single-longitudinal mode (SLM) narrow linewidth broadband tunable Brillouin random laser, including two segment dispersion compensated fibers (DCFs), in which enough narrowband Brillouin gain provided by a 2-km-length DCF to overcome the cavity loss, and Rayleigh backscattering (RBS) provided by a 1-km-length DCF form a mirrorless open cavity to continuously compress the laser linewidth. Compared to ordinary single mode fibers, DCF has an enhanced stimulated Brillouin scattering gain coefficient and RBS coefficient, which is attributed to its small core diameter structure, making the laser more compact and stable. Stronger random feedback effectively lowers the laser threshold, and enough Brillouin gain for multiple amplifications in random mode makes SLM operations more accessible. The proposed laser is with a threshold of ∼11 mW and an optical signal-to-noise ratio (OSNR) of ∼55.75 dB, the 3-dB linewidth and linewidth compression ratio of the output laser reaches ∼550 Hz and ∼236, respectively. By changing the wavelength of the pump laser, the laser wavelength can be continuously tuned in a broad wavelength range, which is only limited by tunable range of Brillouin pump laser. The laser wavelength fluctuation of 0.02 nm and the OSNR fluctuation of about 3 dB in a 30-minute measure period, indicating that the laser is with a good stability.

Experimental research on mechanical properties and elastic modulus of glass fiber reinforced concrete

By adding ordinary glass fiber and alkali resistant glass fiber into concrete, the development of axial compressive strength, axial tensile strength and elastic modulus of concrete are studied. The results show that with the increase of glass fiber, the axial compressive strength increases first and then decreases; the axial tensile strength increases; the elastic modulus decreases. The results show that glass fiber can improve the strength of concrete, and reduce the elastic modulus.

Coupling of laser diode with cylindrical microlens fabricated on the tip of single-mode photonic crystal fiber: prediction of coupling optics by ABCD matrix

Abstract We report the theoretical prediction of the coupling optics involving a laser diode and photonic crystal fiber which contains on its tip cylindrical microlens. The analysis is based on relevant ABCD matrix formalism. Though photonic crystal fiber has very large single-mode region, we carry on the investigation for two commonly used wavelengths such as 1.3 µm and 1.5 µm. For the particular kind of photonic crystal having specific value of air filling ratio and hole pitch, we have optimized the distance of laser diode from the microlens in order to get maximum value of coupling efficiency for each value of radius of cylindrical microlens. Incidentally, we have got here maximum coupling efficiency to the extent of 86.99 % at the wavelength 1.3 µm when the radius of the cylindrical microlens is 8.5 µm and effective spot size of the fiber is 4.433909 µm. Further, the maximum efficiency becomes 91.78 % at 1.3 µm when the radius of the cylindrical microlens is 4.0 µm and effective spot size of the fiber is 1.859907 µm. It has been shown that wavelength 1.5 µm is not so coupling efficient like 1.3 µm. Moreover, it has been shown that with same set of relevant parameters, PCF is more coupling efficient compared to ordinary graded index fiber. Thus the present work generates scope for varying different photonic crystal fiber parameters and the wavelengths of source as well for enhancing the coupling efficiency. Accordingly, the present analysis will be extremely helpful for design of efficient coupler of this kind.

Effect of whisker toughening on the dynamic properties of hybrid fiber concrete

In the present study, the test analyzed the effect of calcium carbonate whisker powder on the properties of hybrid fiber concrete incorporated with basalt and mesh polypropylene fibers. Mixed and single fiber concrete were set up for comparative study. The strain rate, pore change, and morphology of concrete were tested by split Hopkinson pressure bar (SHPB), NMR, and SEM, respectively, and the action mechanism of the calcium carbonate whisker hybrid fiber concrete was analyzed. The study showed that the addition of whiskers and hybrid fibers to concrete can effectively improve the compressive and flexural strengths compared with ordinary and single fiber concrete. The porosity optimization of the whisker toughening hybrid fiber concrete was remarkably optimized, and the strength and toughness are particularly improved. The strain rate was enhanced by improving the impact resistance under the impact load. Results also revealed that whiskers and two kinds of fibers have different sizes and physical and mechanical properties, which enable their functioning in different dimensions and damage stages to improve the strength and toughness of the concrete.

Distributed Detection and Acoustic Emission Waveform Retrieval of Cable Joint Partial Discharge

Distributed detection and acoustic emission (AE) waveform retrieval of partial discharge (PD) in power cable joints are significant but challenging tasks. In this paper, we proposed a cable joint PD detection method based on optical fiber distributed acoustic sensing (DAS). Ordinary single-mode optical fiber (SMF) was wound on the outer semiconductive layer to obtain sufficient sensitivity. Coherent optical time domain reflection (COTDR) principle was utilized to detect the phase variation and locate the PDs. The AE waveforms were retrieved by Fourier integration and difference operation. The experimental results indicated that the sensing system had the ability of multi-point monitoring. The PD AE waveforms caused by conductor spike and insulation air gap defects were accurately retrieved.

Experimental feasibility investigation on wearability of cloth-type electronic devices composed of functional polyvinylidene difluoride (PVDF) fibers

In the fabrication of fabric-type electronic devices, especially mobile wearable devices, various electrical functions such as sensing, actuation, and energy harvesting can be realized using complex fibrous electrical components and the associated techniques such as weaving and wiring. This study introduces a hybrid cloth-type electronic device composed of PVDF and ordinary fiber yarns. Moreover, experimental protocols for evaluating the electrical performances of cloth-type electronic devices are used to check the feasibility of the proposed wearable electronic device. The magnitude of the generated voltage signal depending on the weaving pattern and types of functional fibers under impact loading were experimentally investigated, and the most appropriate weaving pattern was suggested. To check the serviceability of the proposed cloth-type wearable device, its performance was tested under various hygrothermal environmental conditions. After conducting several electro-mechanical tests and a washing test, the proposed hybrid cloth-type electronic device was found to have adequate potential for use in self-powered wearable electronic devices.

Application of 2D Images in Visual and Tactile Dimensions of Fiber Art Design

With people’s higher and higher spiritual requirements, fiber art is more common in people’s lives. From ordinary fiber materials to handicrafts and daily necessities, there are shadows of fiber art. This paper aims to study the application of two-dimensional images in the visual and tactile dimensions of fiber art design. This paper proposes a three-dimensional simulation of two-dimensional images of art based on deep learning technology to achieve the purpose of convenient display and also analyzes the feature extraction in fiber art. In order to comprehensively compare the performance of the algorithms, this paper compares the performance of four categories: reconstruction speed, number of reconstructed point clouds, diversity of reconstructable categories, and reconstruction stability. The experimental results show that the number of point clouds obtained by the algorithm proposed in this paper far exceeds the other two reconstruction processes, and the average time is 34.4 min. This also shows that such algorithmic processes are more robust to clothing diversity.

Graphene and its application: A review

The extraordinary properties of graphene have been acknowledged as an efficient reinforcement for cementitious composites, enabling the construction of more clever, durable, and long-lasting building materials. Graphene-based reinforcing fillers, however, are unable to be directly included into cementitious composites for industrial manufacture due to dispersion problems and high prices. Therefore, it seems that commercialising graphene for cementitious materials may be more feasible if it were combined with ordinary fibres to reinforce cement. Recent research findings on the use of graphene in fiber-reinforced cementitious composites were evaluated critically and synthetically in this review study. First, the processes for producing and describing hybrid graphene-fiber fillers are discussed. Then, a summary of mechanical reinforcing mechanisms is presented, emphasising the significant contributions made by the nucleation effect, filling effect, interfacial bonding effect, and toughening effect. The study continues by describing in detail the enhancements made to the mechanical, electrical conductivity, electromagnetic interference shielding, and multifunctional interfacial properties of graphene-fiber reinforced cementitious composites. Finally, key challenges likely consequences are examined in order to provide useful recommendations and provide guidance for applicable future studies.