Search results for: steel channel beam
3285 Study of the Efficiency of a Synthetic Wax for Corrosion Protection of Steel in Aggressive Environments
Authors: Laidi Babouri
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The remarkable properties of steel, such as hardness and impact resistance, motivate their use in the automotive manufacturing industry. However, due to the very vulnerable environmental conditions of use, the steel that makes up the car body can corrode. This situation is motivating more and more automobile manufacturers to develop research to develop processes minimizing the rate of degradation of the physicomechanical properties of these materials. The present work falls within this perspective; it presents the results of a research study focused on the use of synthetic wax for the protection of steel, type XES (DC04), against corrosion in aggressive environments. The media used in this study are an acid medium with a pH=5.6, a 3% chloride medium, and a dry medium. Evaluation of the protective power of synthetic wax in different environments was carried out using mass loss techniques (immersion), completed by electrochemical techniques (stationary and transient). The results of the immersion of the steel samples, with a surface area of (1.44 cm²), in the various media, for a period of 30 days, using the immersion technique, showed high protective efficiency of synthetic wax in acidic and saline environments, with a lesser degree in a dry environment. Moreover, the study of the protective power, using electrochemical techniques, confirmed the results obtained in static mode (loss of mass), the protective efficiency of synthetic wax, against the corrosion of steel, in different environments, which reaches a maximum rate of 99.87% in a saline environment.Keywords: corrosion, steel, industrial wax, environment, mass loss, electrochemical techniques
Procedia PDF Downloads 503284 Research of Strong-Column-Weak-Beam Criteria of Reinforced Concrete Frames Subjected to Biaxial Seismic Excitation
Authors: Chong Zhang, Mu-Xuan Tao
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In several earthquakes, numerous reinforced concrete (RC) frames subjected to seismic excitation demonstrated a collapse pattern characterized by column hinges, though designed according to the Strong-Column-Weak-Beam (S-C-W-B) criteria. The effect of biaxial seismic excitation on the disparity between design and actual performance is carefully investigated in this article. First, a modified load contour method is proposed to derive a closed-form equation of biaxial bending moment strength, which is verified by numerical and experimental tests. Afterwards, a group of time history analyses of a simple frame modeled by fiber beam-column elements subjected to biaxial seismic excitation are conducted to verify that the current S-C-W-B criteria are not adequate to prevent the occurrence of column hinges. A biaxial over-strength factor is developed based on the proposed equation, and the reinforcement of columns is appropriately amplified with this factor to prevent the occurrence of column hinges under biaxial excitation, which is proved to be effective by another group of time history analyses.Keywords: biaxial bending moment capacity, biaxial seismic excitation, fiber beam model, load contour method, strong-column-weak-beam
Procedia PDF Downloads 773283 Study of the Best Algorithm to Estimate Sunshine Duration from Global Radiation on Horizontal Surface for Tropical Region
Authors: Tovondahiniriko Fanjirindratovo, Olga Ramiarinjanahary, Paulisimone Rasoavonjy
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The sunshine duration, which is the sum of all the moments when the solar beam radiation is up to a minimal value, is an important parameter for climatology, tourism, agriculture and solar energy. Its measure is usually given by a pyrheliometer installed on a two-axis solar tracker. Due to the high cost of this device and the availability of global radiation on a horizontal surface, on the other hand, several studies have been done to make a correlation between global radiation and sunshine duration. Most of these studies are fitted for the northern hemisphere using a pyrheliometric database. The aim of the present work is to list and assess all the existing methods and apply them to Reunion Island, a tropical region in the southern hemisphere. Using a database of ten years, global, diffuse and beam radiation for a horizontal surface are employed in order to evaluate the uncertainty of existing algorithms for a tropical region. The methodology is based on indirect comparison because the solar beam radiation is not measured but calculated by the beam radiation on a horizontal surface and the sun elevation angle.Keywords: Carpentras method, data fitting, global radiation, sunshine duration, Slob and Monna algorithm, step algorithm
Procedia PDF Downloads 1023282 Sensitivity Analysis of Interference of Localised Corrosion on Bending Capacity of a Corroded RC Beam
Authors: Mohammad Mahdi Kioumarsi
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In this paper, using the response surface method (RSM), tornado diagram method and non-linear finite element analysis, the effect of four parameters on residual bending capacity of a corroded RC beam was investigated. The parameters considered are amount of localised cross section reduction, ratio of pit distance on adjacent bars to rebar distance, concrete compressive strength, and rebar tensile strength. The focus is on the influence on the bending ultimate limit state. Based on the obtained results, the effects of the ratio of pit distance to rebar distance (Lp⁄Lr) and the ratio of the localised cross section reduction to the original area of the rebar (Apit⁄A0) were found significant. The interference of localised corrosion on adjacent reinforcement bars reduces the bending capacity of under-reinforced concrete beam. Using the sensitivity analysis could lead to recognize uncertainty parameters, which have the most influences on the performance of the structure.Keywords: localised corrosion, concrete beam, sensitivity analyses, ultimate capacity
Procedia PDF Downloads 2343281 Heat and Mass Transfer of an Oscillating Flow in a Porous Channel with Chemical Reaction
Authors: Zahra Neffah, Henda Kahalerras
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A numerical study is made in a parallel-plate porous channel subjected to an oscillating flow and an exothermic chemical reaction on its walls. The flow field in the porous region is modeled by the Darcy–Brinkman–Forchheimer model and the finite volume method is used to solve the governing equations. The effects of the modified Frank-Kamenetskii (FKm) and Damköhler (Dm) numbers, the amplitude of oscillation (A), and the Strouhal number (St) are examined. The main results show an increase of heat and mass transfer rates with A and St, and their decrease with FKm and Dm.Keywords: chemical reaction, heat and mass transfer, oscillating flow, porous channel
Procedia PDF Downloads 3893280 The Reality of the Application of Environmental Accounting in the Iron and Steel Sector in Libya: A Case Study in the Libyan Iron and Steel Company, Misurata, Libya
Authors: Eltaib Elzarrouk E. E. Abdalmajeed
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This research aims at shedding the light on environmental accounting, which is considered to be one of the most important areas in accounting discipline. It also studies the reality of the application of environmental accounting in the iron and steel sector in Libya. The questionnaire of this study was used for data collection from respondents who are employed in the Libyan Iron and Steel Company, Misurata – Libya (LISC). The Statistical Package for Social Sciences (SPSS) was also used for the analysis. Several important results were revealed include that the (LISC) relatively applies environmental accounting, and it faces some obstacles in conducting its application. Furthermore, the researched company realizes the importance of applying environmental accounting as a need for quality procedures. It was suggested that training courses should be held periodically to spread the awareness of environmental accounting environment. In addition, social responsibility and sustainability should be taken into consideration in the company's strategic plan.Keywords: environment, environmental accounting, environmental accounting disclosure, The Libyan Iron and Steel Company, Misurata- Libya (LISC)
Procedia PDF Downloads 1233279 Structural Properties of RC Beam with Progression of Corrosion Induced Delamination Cracking
Authors: Anupam Saxena, Achin Agrawal, Rishabh Shukla, S. Mandal
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It is quite important that the properties of structural elements do not change significantly before and after cracking, and if they do, it adversely affects the structure. Corrosion in rebars causes cracking in concrete which can lead to the change in properties of beam. In the present study, two RC beams with same flexural strength but with different reinforcement arrangements are considered and modelling of cracks of RC beams has been done at different degrees of corrosion in the case of delamination using boundary conditions of Three Point Bending Test. Finite Element Analysis (FEA) has been done at different degree of corrosion to observe the variation of different parameters like modal frequency, Elasticity and Flexural strength in case of delamination. Also, the comparison between two different RC arrangements is made to conclude which one of them is more suitable.Keywords: delamination, elasticity, FEA, flexural strength, modal frequency, RC beam
Procedia PDF Downloads 3953278 Performance of Fiber Reinforced Self-Compacting Concrete Containing Different Pozzolanic Materials
Authors: Ahmed Fathi Mohamed, Nasir Shafiq, Muhd Fadhil Nuruddin, Ali Elheber Ahmed
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Steel fiber adds to Self-Compacting Concrete (SCC) to enhance it is properties and achieves the requirement. This research work focus on the using of different percentage of steel fiber in SCC mixture contains fly ash and microwave incinerator rice husk ash (MIRHA) as supplementary material. Fibers affect several characteristics of SCC in the fresh and the hardened state. To optimize fiber-reinforced self-compacting concrete (FSCC), The possible fiber content of a given mix composition is an essential input parameter. The aim of the research is to study the properties of fiber reinforced self–compacting (FRSCC) and to develop the expert system/computer program of mix proportion for calculating the steel fiber content and pozzolanic replacement that can be applied to investigate the compressive strength of FSCC mix.Keywords: self-compacting concrete, silica fume, steel fiber, fresh taste
Procedia PDF Downloads 5423277 SCNet: A Vehicle Color Classification Network Based on Spatial Cluster Loss and Channel Attention Mechanism
Authors: Fei Gao, Xinyang Dong, Yisu Ge, Shufang Lu, Libo Weng
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Vehicle color recognition plays an important role in traffic accident investigation. However, due to the influence of illumination, weather, and noise, vehicle color recognition still faces challenges. In this paper, a vehicle color classification network based on spatial cluster loss and channel attention mechanism (SCNet) is proposed for vehicle color recognition. A channel attention module is applied to extract the features of vehicle color representative regions and reduce the weight of nonrepresentative color regions in the channel. The proposed loss function, called spatial clustering loss (SC-loss), consists of two channel-specific components, such as a concentration component and a diversity component. The concentration component forces all feature channels belonging to the same class to be concentrated through the channel cluster. The diversity components impose additional constraints on the channels through the mean distance coefficient, making them mutually exclusive in spatial dimensions. In the comparison experiments, the proposed method can achieve state-of-the-art performance on the public datasets, VCD, and VeRi, which are 96.1% and 96.2%, respectively. In addition, the ablation experiment further proves that SC-loss can effectively improve the accuracy of vehicle color recognition.Keywords: feature extraction, convolutional neural networks, intelligent transportation, vehicle color recognition
Procedia PDF Downloads 1483276 Altered L-Type Calcium Channel Activity in Atrioventricular Nodal Myocytes from Rats with Streptozotocin-Induced Type I Diabetes Mellitus
Authors: Kathryn H. Yull, Lina T. Al Kury, Frank Christopher Howarth
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Cardiovascular diseases are frequently reported in patients with Type-1 Diabetes mellitus (DM). In addition to changes in cardiac muscle inotropy, electrical abnormalities are also commonly observed in these patients. In the present study, using streptozotocin (STZ) rat model of Type-1 DM, we have characterized the changes in L-type calcium channel activity in single atrioventricular nodal (AVN) myocytes. Ionic currents were recorded from AVN myocytes isolated from the hearts of control rats and from those with STZ-induced diabetes. Patch-clamp recordings were used to assess changes in cellular electrical activity in individual myocytes. Type-1 DM significantly altered the cellular characteristics of L-type calcium current (ICaL). A reduction in peak ICaL density was observed, with no corresponding changes in the activation parameters of the current. ICaL also exhibited faster time-dependent inactivation in AVN myocytes from diabetic rats. A negative shift in the voltage dependence of inactivation was also evident. These findings demonstrate that experimentally–induced type-1 DM significantly alters AVN L-type calcium channel cellular electrophysiology. The changes in ion channel activity may underlie the abnormalities in the cardiac electrical function that contribute to the high mortality levels in patients with DM.Keywords: cardiac, ion-channel, diabetes, atrioventricular node, calcium channel
Procedia PDF Downloads 3143275 Experimental Studies on Flexural Behaviour on Beam Using Lathe Waste in SIFCON
Authors: R. Saravanakumar, A. Siva, R. Banupriya, K. Balasubramanian
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Slurry infiltrated fibrous concrete (SIFCON) is one of the recently developed construction material that can be considered as a special type of high performance fibre reinforced concrete (HPFRC) with higher fibre content. Fibre reinforced concrete is essentially a composite material in which fibres out of waste having higher modulus of elasticity. SIFCON is a special type of high fibrous concrete and it is having a high cementious content and sand. The matrix usually consists of cement-sand slurry or fluent mortar. The construction industry is in need of finding cost effective materials for increasing the strength of concrete structures hence an endeavour has been made in the present investigations to study the influence of addition of waste material like Lathe waste from workshop at different dosages to the total weight of concrete. The waste of steel scrap material which is available from the lathe is used as a steel fibre for innovative construction industry. To get sustainable and environmental benefits, lathe scrap as recycled fibres with concrete are likely to be used. An experimental program was carried out to investigate the flexural behavior of Slurry infiltrated fibrous concrete (SIFCON) in which the fibres having an aspect ratio of 100 is used. The investigations were done using M25 mix and tests were carried out as per recommended procedures by appropriate codes. SIFCON specimens with 8%, 10% and 12% volume of fraction fibres are used in this study. Test results were presented in comparison of SIFCON with and without conventional steel reinforcement. The load carrying capacity of SIFCON specimen is higher than conventional concrete and it also reduced crack width. In the SIFCON specimen less number of cracks as compared with conventional concrete.Keywords: SIFCON, lathe waste, RCC, fibre volume, flexural behaviour
Procedia PDF Downloads 2963274 Static Strain Aging in Ferritic and Austenitic Stainless Steels
Authors: Songul Kurucay, Mustafa Acarer, Harun Sepet
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Static strain aging occurs when metallic materials are subjected to deformation and then heat treated at low temperatures such as 150-200oC. Static strain aging occurs in BCC metals and results and increasing in yield and tensile strength and decreasing ductility due to carbon and/or nitrogen atoms locking dislocations. The locked dislocations increase yield and tensile strength. In this study, static strain aging behaviors of ferritic and austenitic stainless steel were investigated. Ferritic stainless steel was prestained at %5, %10 and %15 and then aged at 150oC and 200oC for 30 minutes. Austenitic stainless steel was also prestained at %20 and %30 and then heat treated at 200, 400 and 600oC for 30 minutes. After the heat treatment, the tensile test was performed to determine the effect of prestain and heat treatment on the steels. Hardness measurements and detailed microstructure characterization were also done. While AISI 430 ferritic stainless steel sample which was prestained at 15% and aged at 200oC, showed the highest increasing in the yield strength, AISI 304 austenitic stainless steel which was prestained at 30% and aged at 600oC, has the highest yield strength. Microstructure photographs also support the mechanical test results.Keywords: austenitic stainless steel, ferritic stainless steel, static strain aging, tensile strength
Procedia PDF Downloads 4133273 Linear Stability of Convection in an Inclined Channel with Nanofluid Saturated Porous Medium
Authors: D. Srinivasacharya, Nidhi Humnekar
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The goal of this research is to numerically investigate the convection of nanofluid flow in an inclined porous channel. Brownian motion and thermophoresis effects are accounted for by nanofluid. In addition, the flow in the porous region governs Brinkman’s equation. The perturbed state of the generalized eigenvalue problem is obtained using normal mode analysis, and Chebyshev spectral collocation was used to solve this problem. For various values of the governing parameters, the critical wavenumber and critical Rayleigh number are calculated, and preferred modes are identified.Keywords: Brinkman model, inclined channel, nanofluid, linear stability, porous media
Procedia PDF Downloads 923272 Analysis of Various Factors Affecting Hardness and Content of Phases Resulting from 1030 Carbon Steel Heat Treatment Using AC3 Software
Authors: Saeid Shahraki, Mohammad Mahdi Kaekha
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1030 steel, a kind of carbon steel used in homogenization, cold-forming, quenching, and tempering conditions, is generally utilized in small parts resisting medium stress, such as connection foundations, hydraulic cylinders, tiny gears, pins, clamps, automotive normal forging parts, camshafts, levers, pundits, and nuts. In this study, AC3 software was used to measure the effect of carbon and manganese percentage, dimensions and geometry of pieces, the type of the cooling fluid, temperature, and time on hardness and the content of 1030 steel phases. Next, the results are compared with the analytical values obtained from the Lumped Capacity Method.Keywords: 1030Steel, AC3software, heat treatment, lumped capacity method
Procedia PDF Downloads 2603271 Numerical Study of Steel Structures Responses to External Explosions
Authors: Mohammad Abdallah
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Due to the constant increase in terrorist attacks, the research and engineering communities have given significant attention to building performance under explosions. This paper presents a methodology for studying and simulating the dynamic responses of steel structures during external detonations, particularly for accurately investigating the impact of incrementing charge weight on the members total behavior, resistance and failure. Prediction damage method was introduced to evaluate the damage level of the steel members based on five scenarios of explosions. Johnson–Cook strength and failure model have been used as well as ABAQUS finite element code to simulate the explicit dynamic analysis, and antecedent field tests were used to verify the acceptance and accuracy of the proposed material strength and failure model. Based on the structural response, evaluation criteria such as deflection, vertical displacement, drift index, and damage level; the obtained results show the vulnerability of steel columns and un-braced steel frames which are designed and optimized to carry dead and live load to resist and endure blast loading.Keywords: steel structure, blast load, terrorist attacks, charge weight, damage level
Procedia PDF Downloads 3433270 Electrical Properties of Polarization-Induced Aluminum Nitride/Gallium Nitride Heterostructures Homoepitaxially Grown on Aluminum Nitride Sapphire Template by Molecular Beam Epitaxy
Authors: Guanlin Wu, Jiajia Yao, Fang Liu, Junshuai Xue, Jincheng Zhang, Yue Hao
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Owing to the excellent thermal conductivity and ultra-wide bandgap, Aluminum nitride (AlN)/Gallium nitride (GaN) is a highly promising material to achieve high breakdown voltage and output power devices among III-nitrides. In this study, we explore the growth and characterization of polarization-induced AlN/GaN heterostructures using plasma-assisted molecular beam epitaxy (PA-MBE) on AlN-on-sapphire templates. To improve the crystal quality and demonstrate the effectiveness of the PA-MBE approach, a thick AlN buffer of 180 nm was first grown on the AlN-on sapphire template. This buffer acts as a back-barrier to enhance the breakdown characteristic and isolate leakage paths that exist in the interface between the AlN epilayer and the AlN template. A root-mean-square roughness of 0.2 nm over a scanned area of 2×2 µm2 was measured by atomic force microscopy (AFM), and the full-width at half-maximum of (002) and (102) planes on the X-ray rocking curve was 101 and 206 arcsec, respectively, using by high-resolution X-ray diffraction (HR-XRD). The electron mobility of 443 cm2/Vs with a carrier concentration of 2.50×1013 cm-2 at room temperature was achieved in the AlN/GaN heterostructures by using a polarization-induced GaN channel. The low depletion capacitance of 15 pF is resolved by the capacitance-voltage. These results indicate that the polarization-induced AlN/GaN heterostructures have great potential for next-generation high-temperature, high-frequency, and high-power electronics.Keywords: AlN, GaN, MBE, heterostructures
Procedia PDF Downloads 613269 Design of a Compact Herriott Cell for Heat Flux Measurement Applications
Authors: R. G. Ramírez-Chavarría, C. Sánchez-Pérez, V. Argueta-Díaz
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In this paper we present the design of an optical device based on a Herriott multi-pass cell fabricated on a small sized acrylic slab for heat flux measurements using the deflection of a laser beam propagating inside the cell. The beam deflection is produced by the heat flux conducted to the acrylic slab due to a gradient in the refractive index. The use of a long path cell as the sensitive element in this measurement device, gives the possibility of high sensitivity within a small size device. We present the optical design as well as some experimental results in order to validate the device’s operation principle.Keywords: heat flux, Herriott cell, optical beam deflection, thermal conductivity
Procedia PDF Downloads 6223268 Reinforcing Fibre Reinforced Polymer (FRP) Bridge Decks with Steel Plates
Authors: M. Alpaslan Koroglu
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Fibre reinforced polymer (FRP) bridge decks have become an innovative alternative, and they have offered many advantages, and this has been increasing attention for applications in not only reinforcement of existing bridges decks but also construction of new bridges decks. The advantages of these FRP decks are; lightweight, high-strength FRP materials, corrosion resistance. However, this high strength deck is not ductile. In this study, the behaviour of hybrid FRP-steel decks are investigated. All FRP decks was analysed with the commercial package ABAQUS. In the FE model, the webs and flanges were discretised by 4 nodes shell elements. A full composite action between the steel and the FRP composite was assumed in the FE analysis because the bond-slip behaviour was unknown at that time. The performance of the proposed hybrid FRP deck panel with steel plates was evaluated by means of FE analysis.Keywords: FRP, deck, bridge, finite element
Procedia PDF Downloads 4483267 Studies on the Teaching Pedagogy and Effectiveness for the Multi-Channel Storytelling for Social Media, Cinema, Game, and Streaming Platform: Case Studies of Squid Game
Authors: Chan Ka Lok Sobel
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The rapid evolution of digital media platforms has given rise to new forms of narrative engagement, particularly through multi-channel storytelling. This research focuses on exploring the teaching pedagogy and effectiveness of multi-channel storytelling for social media, cinema, games, and streaming platforms. The study employs case studies of the popular series "Squid Game" to investigate the diverse pedagogical approaches and strategies used in teaching multi-channel storytelling. Through qualitative research methods, including interviews, surveys, and content analysis, the research assesses the effectiveness of these approaches in terms of student engagement, knowledge acquisition, critical thinking skills, and the development of digital literacy. The findings contribute to understanding best practices for incorporating multi-channel storytelling into educational contexts and enhancing learning outcomes in the digital media landscape.Keywords: digital literacy, game-based learning, artificial intelligence, animation production, educational technology
Procedia PDF Downloads 653266 A Comparative Study for the Axial Load Capacity of Circular High Strength CFST Columns
Authors: Eylem Guzel, Faruk Osmanoglu, Muhammet Kurucu
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The concrete filled steel tube (CFST) columns are commonly used in construction applications such as high-rise buildings and bridges owing to its lots of remarkable benefits. The use of concrete-filled steel tube columns provides large areas by reduction in cross-sectional area of columns. The main aim of this study is to examine the axial load capacities of circular high strength concrete-filled steel tube columns according to Eurocode 4 (EC4) and Chinese Code (DL/T). The results showed that the predictions of EC4 and Chinese Code DL/T are unsafe for all specimens.Keywords: concrete-filled steel tube column, axial load capacity, Chinese code, Australian standard
Procedia PDF Downloads 3723265 A Composite Beam Element Based on Global-Local Superposition Theory for Prediction of Delamination in Composite Laminates
Authors: Charles Mota Possatti Júnior, André Schwanz de Lima, Maurício Vicente Donadon, Alfredo Rocha de Faria
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An interlaminar damage model is combined with a beam element formulation based on global-local superposition to assess delamination in composite laminates. The variations in the mechanical properties in the laminate, generated by the presence of delamination, are calculated as a function of the displacements in the interface layers. The global-local superposition of displacement fields ensures the zig-zag behaviour of stresses and displacement, and the number of degrees of freedom (DOFs) is independent of the number of layers. The displacements and stresses are calculated as a function of DOFs commonly used in traditional beam elements. Finally, the finite element(FE) formulation is extended to handle cases of different thicknesses, and then the FE model predictions are compared with results obtained from analytical solutions and commercial finite element codes.Keywords: delamination, global-local superposition theory, single beam element, zig-zag, interlaminar damage model
Procedia PDF Downloads 913264 Cavity-Type Periodically-Poled LiNbO3 Device for Highly-Efficient Third-Harmonic Generation
Authors: Isao Tomita
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We develop a periodically-poled LiNbO3 (PPLN) device for highly-efficient third-harmonic generation (THG), where the THG efficiency is enhanced with a cavity. THG can usually be produced via χ(3)-nonlinear materials by optical pumping with very high pump-power. Instead, we here propose THG by moderate-power pumping through a specially-designed PPLN device containing only χ(2)-nonlinearity, where sum-frequency generation in the χ(2) process is employed for the mixing of a pump beam and a second-harmonic-generation (SHG) beam produced from the pump beam. The cavity is designed to increase the SHG power with dichroic mirrors attached to both ends of the device that perfectly reflect the SHG beam back to the device and yet let the pump and THG beams pass through the mirrors. This brings about a THG-power enhancement because of THG power proportional to the enhanced SHG power. We examine the THG-efficiency dependence on the mirror reflectance and show that very high THG-efficiency is obtained at moderate pump-power when compared with that of a cavity-free PPLN device.Keywords: cavity, periodically-poled LiNbO₃, sum-frequency generation, third-harmonic generation
Procedia PDF Downloads 2393263 Experimental Study of Heat Transfer and Pressure Drop in Serpentine Channel Water Cooler Heat Sink
Authors: Hao Xiaohong, Wu Zongxiang, Chen Xuefeng
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With the high power density and high integration of electronic devices, their heat flux has been increasing rapidly. Therefore, an effective cooling technology is essential for the reliability and efficient operation of electronic devices. Liquid cooling is studied increasingly widely for its higher heat transfer efficiency. Serpentine channels are superior in the augmentation of single-phase convective heat transfer because of their better channel velocity distribution. In this paper, eight different frame sizes water-cooled serpentine channel heat sinks are designed to study the heat transfer and pressure drop characteristics. With water as the working fluid, experiment setup is established and the results showed the effect of different channel width, fin thickness and number of channels on thermal resistance and pressure drop.Keywords: heat transfer, experiment, serpentine heat sink, pressure drop
Procedia PDF Downloads 4303262 Vibration of Nonhomogeneous Timoshenko Nanobeam Resting on Winkler-Pasternak Foundation
Authors: Somnath Karmakar, S. Chakraverty
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This work investigates the vibration of nonhomogeneous Timoshenko nanobeam resting on the Winkler-Pasternak foundation. Eringen’s nonlocal theory has been used to investigate small-scale effects. The Differential Quadrature method is used to obtain the frequency parameters with various classical boundary conditions. The nonhomogeneous beam model has been considered, where Young’s modulus and density of the beam material vary linearly and quadratically. Convergence of frequency parameters is also discussed. The influence of mechanical properties and scaling parameters on vibration frequencies are investigated for different boundary conditions.Keywords: Timoshenko beam, Eringen's nonlocal theory, differential quadrature method, nonhomogeneous nanobeam
Procedia PDF Downloads 953261 Numerical Simulation of Encased Composite Column Bases Subjected to Cyclic Loading
Authors: Eman Ismail, Adnan Masri
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Energy dissipation in ductile moment frames occurs mainly through plastic hinge rotations in its members (beams and columns). Generally, plastic hinge locations are pre-determined and limited to the beam ends, where columns are designed to remain elastic in order to avoid premature instability (aka story mechanisms) with the exception of column bases, where a base is 'fixed' in order to provide higher stiffness and stability and to form a plastic hinge. Plastic hinging at steel column bases in ductile moment frames using conventional base connection details is accompanied by several complications (thicker and heavily stiffened connections, larger embedment depths, thicker foundation to accommodate anchor rod embedment, etc.). An encased composite base connection is proposed where a segment of the column beginning at the base up to a certain point along its height is encased in reinforced concrete with headed shear studs welded to the column flanges used to connect the column to the concrete encasement. When the connection is flexurally loaded, stresses are transferred to a reinforced concrete encasement through the headed shear studs, and thereby transferred to the foundation by reinforced concrete mechanics, and axial column forces are transferred through the base-plate assembly. Horizontal base reactions are expected to be transferred by the direct bearing of the outer and inner faces of the flanges; however, investigation of this mechanism is not within the scope of this research. The inelastic and cyclic behavior of the connection will be investigated where it will be subjected to reversed cyclic loading, and rotational ductility will be observed in cases of yielding mechanisms where yielding occurs as flexural yielding in the beam-column, shear yielding in headed studs, and flexural yielding of the reinforced concrete encasement. The findings of this research show that the connection is capable of achieving satisfactory levels of ductility in certain conditions given proper detailing and proportioning of elements.Keywords: seismic design, plastic mechanisms steel structure, moment frame, composite construction
Procedia PDF Downloads 1073260 Evaluation on Effective Size and Hysteresis Characteristics of CHS Damper
Authors: Daniel Y. Abebe, Jaehyouk Choi
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This study aims to evaluate the effective size and hysteresis characteristics of Circular Hollow Steel (CHS) damper. CHS damper is among steel dampers which are used widely for seismic energy dissipation because they are easy to install, maintain and are low cost. CHS damper dissipates seismic energy through metallic deformation due to the geometrical elasticity of circular shape and fatigue resistance around connection part. After calculating the effective size, which is found to be height to diameter ratio of √ ("3”), nonlinear FE analyses were conducted to evaluate the hysteresis characteristics. To verify the analysis simulation quasi static loading was carried out and the result was compared and satisfactory result was obtained.Keywords: SS400 steel, circular hollow steel damper, effective size, quasi static loading, FE analysis
Procedia PDF Downloads 4033259 Tapered Double Cantilever Beam: Evaluation of the Test Set-up for Self-Healing Polymers
Authors: Eleni Tsangouri, Xander Hillewaere, David Garoz Gómez, Dimitrios Aggelis, Filip Du Prez, Danny Van Hemelrijck
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Tapered Double Cantilever Beam (TDCB) is the most commonly used test set-up to evaluate the self-healing feature of thermoset polymers autonomously activated in the presence of crack. TDCB is a modification of the established fracture mechanics set-up of Double Cantilever Beam and is designed to provide constant strain energy release rate with crack length under stable load evolution (mode-I). In this study, the damage of virgin and autonomously healed TDCB polymer samples is evaluated considering the load-crack opening diagram, the strain maps provided by Digital Image Correlation technique and the fractography maps given by optical microscopy. It is shown that the pre-crack introduced prior to testing (razor blade tapping), the loading rate and the length of the side groove are the features that dominate the crack propagation and lead to inconstant fracture energy release rate.Keywords: polymers, autonomous healing, fracture, tapered double cantilever beam
Procedia PDF Downloads 3303258 Numerical Study on Ultimate Capacity of Bi-Modulus Beam-Column
Authors: Zhiming Ye, Dejiang Wang, Huiling Zhao
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Development of the technology demands a higher-level research on the mechanical behavior of materials. Structural members made of bi-modulus materials have different elastic modulus when they are under tension and compression. The stress and strain states of the point effect on the elastic modulus and Poisson ratio of every point in the bi-modulus material body. Accompanied by the uncertainty and nonlinearity of the elastic constitutive relation is the complicated nonlinear problem of the bi-modulus members. In this paper, the small displacement and large displacement finite element method for the bi-modulus members have been proposed. Displacement nonlinearity is considered in the elastic constitutive equation. Mechanical behavior of slender bi-modulus beam-column under different boundary conditions and loading patterns has been simulated by the proposed method. The influence factors on the ultimate bearing capacity of slender beam and columns have been studied. The results show that as the ratio of tensile modulus to compressive modulus increases, the error of the simulation employing the same elastic modulus theory exceeds the engineering permissible error.Keywords: bi-modulus, ultimate capacity, beam-column, nonlinearity
Procedia PDF Downloads 3873257 Morphological Characteristics and Development of the Estuary Area of Lam River, Vietnam
Authors: Hai Nguyen Tien
Abstract:
On the basis of the structure of alluvial sediments explained by echo sounding data and remote sensing images, the following results can be given: The estuary of Lam river (from Ben Thuy bridge to Cua Hoi) is divided into 3 channel (location is calculated according to the river bank on the Nghe An province) : i) channel I (from Ben Thuy bridge to Hung Hoa) is the branching river; ii) channel II (from Hung Hoa to Nghi Thai is a channel develops in a meandering direction with a concave side toward Ha Tinh province; iii) channel III, from Nghi Thai to Cua Hoi is a channel develops in a meandering direction with a concave side toward Nghe An province. This estuary area is formed in the period from after the sea level dropped below 0m (current water level) to the present: i) Chanel II developed moving towards Ha Tinh provnce; ii) Chanel III developed moving towards Nghe An province; iii) In chanel I, a second river branch is formed because the flow of river cuts through the Hong Lam- Hong Nhat mudflat, at the same time creating an island. Morphological characteristics of the estuary area of Lam River are the main result of erosion and deposition activities corresponding to two water levels: low water level below 0 m and water level 0 m (current water level). Characteristics of the sediment layers on the riverbed in the estuary can be used to determine the sea levels in Late Holocene–Present.Keywords: Lam River, development, Cua Hoi, river morphology
Procedia PDF Downloads 1043256 Bandwidth Efficient Cluster Based Collision Avoidance Multicasting Protocol in VANETs
Authors: Navneet Kaur, Amarpreet Singh
Abstract:
In Vehicular Adhoc Networks, Data Dissemination is a challenging task. There are number of techniques, types and protocols available for disseminating the data but in order to preserve limited bandwidth and to disseminate maximum data over networks makes it more challenging. There are broadcasting, multicasting and geocasting based protocols. Multicasting based protocols are found to be best for conserving the bandwidth. One such protocol named BEAM exists that improves the performance of Vehicular Adhoc Networks by reducing the number of in-network message transactions and thereby efficiently utilizing the bandwidth during an emergency situation. But this protocol may result in multicar chain collision as there was no V2V communication. So, this paper proposes a new protocol named Enhanced Bandwidth Efficient Cluster Based Multicasting Protocol (EBECM) that will overcome the limitations of existing BEAM protocol. And Simulation results will show the improved performance of EBECM in terms of Routing overhead, throughput and PDR when compared with BEAM protocol.Keywords: BEAM, data dissemination, emergency situation, vehicular adhoc network
Procedia PDF Downloads 324