Search results for: bond slip relationship
7185 Research of Interaction between Layers of Compressed Composite Columns
Authors: Daumantas Zidanavicius
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In order to investigate the bond between concrete and steel in the circular steel tube column filled with concrete, the 7 series of specimens were tested with the same geometrical parameters but different concrete properties. Two types of specimens were chosen. For the first type, the expansive additives to the concrete mixture were taken to increase internal forces. And for the second type, mechanical components were used. All 7 series of the short columns were modeled by FEM and tested experimentally. In the work, big attention was taken to the bond-slip models between steel and concrete. Results show that additives to concrete let increase the bond strength up to two times and the mechanical anchorage –up to 6 times compared to control specimens without additives and anchorage.Keywords: concrete filled steel tube, push-out test, bond slip relationship, bond stress distribution
Procedia PDF Downloads 1217184 Bond-Slip Response of Reinforcing Bars Embedded in High Performance Fiber Reinforced Cement Composites
Authors: Lee Siong Wee, Tan Kang Hai, Yang En-Hua
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This paper presents the results of an experimental study undertaken to evaluate the local bond stress-slip response of short embedment of reinforcing bars in normal concrete (NC) and high performance fiber reinforced cement composites (HPFRCC) blocks. Long embedment was investigated as well to gain insights on the distribution of strain, slip, bar stress and bond stress along the bar especially in post-yield range. A total of 12 specimens were tested, by means of pull-out of the reinforcing bars from concrete blocks. It was found that the enhancement of local bond strength can be reached up to 50% and ductility of the bond behavior was improved significantly if HPFRCC is used. Also, under a constant strain at loaded end, HPFRCC has delayed yielding of bars at other location from the loaded end. Hence, the reduction of bond stress was slower for HPFRCC in comparison with NC. Due to the same reason, the total slips at loaded end for HPFRCC was smaller than NC as expected. Test results indicated that HPFRCC has better bond slip behavior which makes it a suitable material to be employed in anchorage zone such as beam-column joints.Keywords: bond stress, high performance fiber reinforced cement composites, slip, strain
Procedia PDF Downloads 4917183 An Experimental Investigation of Bond Properties of Reinforcements Embedded in Geopolymer Concrete
Authors: Jee-Sang Kim, Jong Ho Park
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Geopolymer concretes are a new class of construction materials that have emerged as an alternative to Ordinary Portland cement concrete. Considerable researches have been carried out on material development of geopolymer concrete, however, a few studies have been reported on the structural use of them. This paper presents the bond behaviors of reinforcement embedded in fly ash based geopolymer concrete. The development lengths of reinforcement for various compressive strengths of concrete, 20, 30 and 40 MPa, and reinforcement diameters, 10, 16, and 25 mm are investigated. Total 27 specimens were manufactured and pull-out test according to EN 10080 was applied to measure bond strength and slips between concrete and reinforcements. The average bond strengths decreased from 23.06MPa to 17.26 MPa, as the diameters of reinforcements increased from 10mm to 25mm. The compressive strength levels of geopolymer concrete showed no significant influence on bond strengths in this study. Also, the bond-slip relations between geopolymer concrete and reinforcement are derived using non-linear regression analysis for various experimental conditions.Keywords: bond-slip relation, bond strength, geopolymer concrete, pull-out test
Procedia PDF Downloads 3447182 Modified Tendon Model Considered Structural Nonlinearity in PSC Structures
Authors: Yangsu Kwon, Hyo-Gyoung Kwak
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Nonlinear tendon constitutive model for nonlinear analysis of pre-stressed concrete structures are presented. Since the post-cracking behavior of concrete structures, in which bonded reinforcements such as tendons and/or reinforcing steels are embedded, depends on many influencing factors(the tensile strength of concrete, anchorage length of reinforcements, concrete cover, and steel spacing) that are deeply related to the bond characteristics between concrete and reinforcements, consideration of the tension stiffening effect on the basis of the bond-slip mechanism is necessary to evaluate ultimate resisting capacity of structures. In this paper, an improved tendon model, which considering the slip effect between concrete and tendon, and effect of tension stiffening, is suggested. The validity of the proposed models is established by comparing between the analytical results and experimental results in pre-stressed concrete beams.Keywords: bond-slip, prestressed concrete, tendon, ultimate strength
Procedia PDF Downloads 4867181 Finite Element Analysis of Steel-Concrete Composite Structures Considering Bond-Slip Effect
Authors: WonHo Lee, Hyo-Gyoung Kwak
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A numerical model considering slip behavior of steel-concrete composite structure is introduced. This model is based on a linear bond stress-slip relation along the interface. Single node was considered at the interface of steel and concrete member in finite element analysis, and it improves analytical problems of model that takes double nodes at the interface by adopting spring elements to simulate the partial interaction. The slip behavior is simulated by modifying material properties of steel element contacting concrete according to the derived formulation. Decreased elastic modulus simulates the slip occurrence at the interface and decreased yield strength simulates drop in load capacity of the structure. The model is verified by comparing numerical analysis applying this model with experimental studies. Acknowledgment—This research was supported by a grant(13SCIPA01) from Smart Civil Infrastructure Research Program funded by Ministry of Land, Infrastructure and Transport(MOLIT) of Korea government and Korea Agency for Infrastructure Technology Advancement(KAIA) and financially supported by Korea Ministry of Land, Infrastructure and Transport(MOLIT) as U-City Master and Doctor Course Grant Program.Keywords: bond-slip, composite structure, partial interaction, steel-concrete structure
Procedia PDF Downloads 1737180 Experimental Investigation on the Effect of Bond Thickness on the Interface Behaviour of Fibre Reinforced Polymer Sheet Bonded to Timber
Authors: Abbas Vahedian, Rijun Shrestha, Keith Crews
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The bond mechanism between timber and fibre reinforced polymer (FRP) is relatively complex and is influenced by a number of variables including bond thickness, bond width, bond length, material properties, and geometries. This study investigates the influence of bond thickness on the behaviour of interface, failure mode, and bond strength of externally bonded FRP-to-timber interface. In the present study, 106 single shear joint specimens have been investigated. Experiment results showed that higher layers of FRP increase the ultimate load carrying capacity of interface; conversely, such increase led to decrease the slip of interface. Moreover, samples with more layers of FRPs may fail in a brittle manner without noticeable warning that collapse is imminent.Keywords: fibre reinforced polymer, FRP, single shear test, bond thickness, bond strength
Procedia PDF Downloads 2207179 Moment-Curvature Relation for Nonlinear Analysis of Slender Structural Walls
Authors: E. Dehghan, R. Dehghan
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Generally, the slender structural walls have flexural behavior. Since behavior of bending members can be explained by moment–curvature relation, therefore, an analytical model is proposed based on moment–curvature relation for slender structural walls. The moment–curvature relationships of RC sections are constructed through section analysis. Governing equations describing the bond-slip behavior in walls are derived and applied to moment–curvature relations. For the purpose of removing the imprecision in analytical results, the plastic hinge length is included in the finite element modeling. Finally, correlation studies between analytical and experimental results are conducted with the objective to establish the validity of the proposed algorithms. The results show that bond-slip effect is more significant in walls subjected to larger axial compression load. Moreover, preferable results are obtained when ultimate strain of concrete is assumed conservatively.Keywords: nonlinear analysis, slender structural walls, moment-curvature relation, bond-slip, plastic hinge length
Procedia PDF Downloads 3117178 Effect of Hooked-End Steel Fibres Geometry on Pull-Out Behaviour of Ultra-High Performance Concrete
Authors: Sadoon Abdallah, Mizi Fan, Xiangming Zhou
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In this study, a comprehensive approach has been adopted to examine in detail the effect of various hook geometries on bond-slip characteristics. Extensive single fibre pull-out tests on ultra-high performance matrix with three different W/B ratios and embedded lengths have been carried out. Test results showed that the mechanical deformation of fibre hook is the main mechanism governing the pull-out behaviour. Furthermore, the quantitative analyses have been completed to compare the hook design contribution of 3D, 4D and 5D fibres to assess overall pull-out behaviour. It was also revealed that there is a strong relationship between the magnitude of hook contribution and W/B ratio (i.e. matrix strength). Reducing the W/B ratio from 0.20 to 0.11 greatly optimizes the interfacial transition zone (ITZ) and enables better mobilization, straightening of the hook and results in bond-slip-hardening behaviour.Keywords: bobond mechanisms, fibre-matrix interface, hook geometry, pullout behaviour and water to binder ratio
Procedia PDF Downloads 3747177 Failure Mechanism of Slip-Critical Connections on Curved Surface
Authors: Bae Doobyong, Yoo Jaejun, Park Ilgyu, Choi Seowon, Oh Chang Kook
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Variation of slip coefficient in slip-critical connections of curved plates. This paper presents the results of analytical investigations of slip coefficients in slip-critical bolted connections of curved plates. It may depend on the contact stress distribution at interface and the flexibility of spliced plate. Non-linear FEM analyses have been made to simulate the behavior of bolted connections of curved plates with various radiuses of curvature and thicknesses.Keywords: slip coefficient, curved plates, slip-critical bolted connection, radius of curvature
Procedia PDF Downloads 5057176 Studying the Bond Strength of Geo-Polymer Concrete
Authors: Rama Seshu Doguparti
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This paper presents the experimental investigation on the bond behavior of geo polymer concrete. The bond behavior of geo polymer concrete cubes of grade M35 reinforced with 16 mm TMT rod is analyzed. The results indicate that the bond performance of reinforced geo polymer concrete is good and thus proves its application for construction.Keywords: geo-polymer, concrete, bond strength, behaviour
Procedia PDF Downloads 5007175 Flow of a Second Order Fluid through Constricted Tube with Slip Velocity at Wall Using Integral Method
Authors: Nosheen Zareen Khan, Abdul Majeed Siddiqui, Muhammad Afzal Rana
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The steady flow of a second order fluid through constricted tube with slip velocity at wall is modeled and analyzed theoretically. The governing equations are simplified by implying no slip in radial direction. Based on Karman Pohlhausen procedure polynomial solution for axial velocity profile is presented. An expressions for pressure gradient, shear stress, separation and reattachment points and radial velocity are also calculated. The effect of slip and no slip velocity on velocity, shear stress, pressure gradient are discussed and depicted graphically. It is noted that when Reynolds number increases velocity of the fluid decreases in both slip and no slip conditions. It is also found that the wall shear stress, separation and reattachment points are strongly effected by Reynolds number.Keywords: approximate solution, constricted tube, non-Newtonian fluids, Reynolds number
Procedia PDF Downloads 3907174 Slip Limit Prediction of High-Strength Bolt Joints Based on Local Approach
Authors: Chang He, Hiroshi Tamura, Hiroshi Katsuchi, Jiaqi Wang
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In this study, the aim is to infer the slip limit (static friction limit) of contact interfaces in bolt friction joints by analyzing other bolt friction joints with the same contact surface but in a different shape. By using the Weibull distribution to deal with microelements on the contact surface statistically, the slip limit of a certain type of bolt joint was predicted from other types of bolt joint with the same contact surface. As a result, this research succeeded in predicting the slip limit of bolt joins with different numbers of contact surfaces and with different numbers of bolt rows.Keywords: bolt joints, slip coefficient, finite element method, Weibull distribution
Procedia PDF Downloads 1617173 Improving Inelastic Capacity of Cold-Formed Steel Beams Using Slotted Blotted Connection
Authors: Marzie Shahini, Alireza Bagheri Sabbagh, Rasoul Mirghaderi, Paul C. Davidson
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The focus of this paper is to incorporating the slotted bolted connection into the cold-formed steel (CFS) beams with aim of increasing inelastic bending capacity through bolt slip. An extensive finite element analysis was conducted on the through plate CFS bolted connections which are equipped with the slotted hole. The studied parameters in this paper included the following: CFS beam section geometry, the value of slip force, CFS beam thickness. The numerical results indicate that CFS slotted bolted connection exhibit higher inelastic capacity in terms of ductility compare to connection with standards holes. Moreover, the effect of slip force was analysed by comparing the moment-rotation curves of different models with different slip force value. As a result, as the slip force became lower, there was a tendency for the plastic strain to extend from the CFS member to the connection region.Keywords: slip-critical bolted connection, inelastic capacity, slotted holes, cold-formed steel, bolt slippage, slip force
Procedia PDF Downloads 4277172 Experimental Investigation of Interfacial Bond Strength of Concrete Layers
Authors: Rajkamal Kumar, Sudhir Mishra
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The connections between various elements of concrete structures play a vital role in determining the durability of structures. These connections produce discontinuities and to ensure the monolithic behavior of structures, these connections should be carefully designed. The connections between concrete layers may occur in various situations such as structure repairing and rehabilitation or construction of huge structures with cast-in-situ or pre-cast elements, etc. Bond strength at the interface of these concrete layers should be able to prevent the progressive slip from taking place and it should also ensure satisfactory performance of the structure. Different approaches to enhance the bond strength at interface have been a major area of research. Nowadays, micro-concrete is getting popular as a repair material. Under this ambit, this paper aims to present the experimental results of connections between concrete layers of different age with artificial indentation at interface with two types of repair material: Concrete with same parent concrete composition and ready-mix mortar (micro-concrete), artificial indentations (grooves and holes) were made on the old layer of concrete to increase the bond strength. Curing plays an important role in determining the bond strength. Optimum duration for curing have also been discussed for each type of repair material. Different types of failure patterns have also been mentioned.Keywords: adhesion, cohesion, compressive stress, micro-concrete, shear stress, slant shear test
Procedia PDF Downloads 3267171 Second-Order Slip Flow and Heat Transfer in a Long Isothermal Microchannel
Authors: Huei Chu Weng, Chien-Hung Liu
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This paper presents a study on the effect of second-order slip and jump on forced convection through a long isothermally heated or cooled planar microchannel. The fully developed solutions of thermal flow fields are analytically obtained on the basis of the second-order Maxwell-Burnett slip and Smoluchowski jump boundary conditions. Results reveal that the second-order term in the Karniadakis slip boundary condition is found to contribute a negative velocity slip and then to lead to a higher pressure drop as well as a higher fluid temperature for the heated-wall case or to a lower fluid temperature for the cooled-wall case. These findings are contrary to predictions made by the Deissler model. In addition, the role of second-order slip becomes more significant when the Knudsen number increases.Keywords: microfluidics, forced convection, gas rarefaction, second-order boundary conditions
Procedia PDF Downloads 4457170 Analysis of Slip Flow Heat Transfer between Asymmetrically Heated Parallel Plates
Authors: Hari Mohan Kushwaha, Santosh Kumar Sahu
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In the present study, analysis of heat transfer is carried out in the slip flow region for the fluid flowing between two parallel plates by employing the asymmetric heat fluxes at surface of the plates. The flow is assumed to be hydrodynamically and thermally fully developed for the analysis. The second order velocity slip and viscous dissipation effects are considered for the analysis. Closed form expressions are obtained for the Nusselt number as a function of Knudsen number and modified Brinkman number. The limiting condition of the present prediction for Kn = 0, Kn2 = 0, and Brq1 = 0 is considered and found to agree well with other analytical results.Keywords: Knudsen number, modified Brinkman number, slip flow, velocity slip
Procedia PDF Downloads 3787169 Second-Order Slip Flow and Heat Transfer in a Long Isoflux Microchannel
Authors: Huei Chu Weng
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This paper presents a study on the effect of second-order slip on forced convection through a long isoflux heated or cooled planar microchannel. The fully developed solutions of flow and thermal fields are analytically obtained on the basis of the second-order Maxwell-Burnett slip and local heat flux boundary conditions. Results reveal that when the average flow velocity increases or the wall heat flux amount decreases, the role of thermal creep becomes more insignificant, while the effect of second-order slip becomes larger. The second-order term in the Deissler slip boundary condition is found to contribute a positive velocity slip and then to lead to a lower pressure drop as well as a lower temperature rise for the heated-wall case or to a higher temperature rise for the cooled-wall case. These findings are contrary to predictions made by the Karniadakis slip model.Keywords: microfluidics, forced convection, thermal creep, second-order boundary conditions
Procedia PDF Downloads 3077168 Model-Independent Price Bounds for the Swiss Re Mortality Bond 2003
Authors: Raj Kumari Bahl, Sotirios Sabanis
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In this paper, we are concerned with the valuation of the first Catastrophic Mortality Bond that was launched in the market namely the Swiss Re Mortality Bond 2003. This bond encapsulates the behavior of a well-defined mortality index to generate payoffs for the bondholders. Pricing this bond is a challenging task. We adapt the payoff of the terminal principal of the bond in terms of the payoff of an Asian put option and present an approach to derive model-independent bounds exploiting comonotonic theory. We invoke Jensen’s inequality for the computation of lower bounds and employ Lagrange optimization technique to achieve the upper bound. The success of these bounds is based on the availability of compatible European mortality options in the market. We carry out Monte Carlo simulations to estimate the bond price and illustrate the strength of these bounds across a variety of models. The fact that our bounds are model-independent is a crucial breakthrough in the pricing of catastrophic mortality bonds.Keywords: mortality bond, Swiss Re Bond, mortality index, comonotonicity
Procedia PDF Downloads 2447167 Numerical Simulation of the Bond Behavior Between Concrete and Steel Reinforcing Bars in Specialty Concrete
Authors: Camille A. Issa, Omar Masri
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In the study, the commercial finite element software Abaqus was used to develop a three-dimensional nonlinear finite element model capable of simulating the pull-out test of reinforcing bars from underwater concrete. The results of thirty-two pull-out tests that have different parameters were implemented in the software to study the effect of the concrete cover, the bar size, the use of stirrups, and the compressive strength of concrete. The interaction properties used in the model provided accurate results in comparison with the experimental bond-slip results, thus the model has successfully simulated the pull-out test. The results of the finite element model are used to better understand and visualize the distribution of stresses in each component of the model, and to study the effect of the various parameters used in this study including the role of the stirrups in preventing the stress from reaching to the sides of the specimens.Keywords: pull-out test, bond strength, underwater concrete, nonlinear finite element analysis, abaqus
Procedia PDF Downloads 4347166 Impact of the Xanthan Gum on Rheological Properties of Ceramic Slip
Authors: Souad Hassene Daouadji, Larbi Hammadi, Abdelkrim Hazzab
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The slips intended for the manufacture of ceramics must have rheological properties well-defined in order to bring together the qualities required for the casting step (good fluidity for feeding the molds easily settles while generating a regular settling of the dough and for the dehydration phase of the dough in the mold a setting time relatively short is required to have a sufficient refinement which allows demolding both easy and fast). Many additives haveadded in slip of ceramic in order to improve their rheological properties. In this study, we investigated the impact of xanthan gumon rheological properties of ceramic Slip. The modified Cross model is used to fit the stationary flow curves of ceramic slip at different concentration of xanthan added. The thixotropic behavior studied of mixture ceramic slip-xanthan gumat constant temperature is analyzed by using a structural kinetic model (SKM) in order to account for time dependent effect.Keywords: ceramic slip, xanthan gum, modified cross model, thixotropy, viscosity
Procedia PDF Downloads 1807165 Analysis of Wire Coating for Heat Transfer Flow of a Viscoelastic PTT Fluid with Slip Boundary Conditions
Authors: Rehan Ali Shah, A. M. Siddiqui, T. Haroon
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Slip boundary value problem in wire coating analysis with heat transfer is examined. The fluid is assumed to be viscoelastic PTT (Phan-Thien and Tanner). The rheological constitutive equation of PTT fluid model simulates various polymer melts. Therefore, the current consequences are valuable in a number of realistic situations. Effects of slip parameter γ as well as εDec^2 (viscoelastic index) on the axial velocity, shear stress, normal stress, average velocity, volume flux, thickness of coated wire, shear stress, force on the total wire and temperature distribution profiles have been investigated. A new direction is explored to analyze the flow with the slip parameter. The slippage at the boundaries plays an important role in thickness of coated wire. It is noted that as the slip parameter increases the flow rate and thickness of coated wire increases while, temperature distribution decreases. The results reduce to no slip when the slip parameter is vanished. Furthermore, we can obtain the results for Maxwell and viscous model by setting ε and λ equal to zero respectively.Keywords: wire coating, straight annular die, PTT fluid, heat transfer, slip boundary conditions
Procedia PDF Downloads 3567164 Slip Suppression Sliding Mode Control with Various Chattering Functions
Authors: Shun Horikoshi, Tohru Kawabe
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This study presents performance analysis results of SMC (Sliding mode control) with changing the chattering functions applied to slip suppression problem of electric vehicles (EVs). In SMC, chattering phenomenon always occurs through high frequency switching of the control inputs. It is undesirable phenomenon and degrade the control performance, since it causes the oscillations of the control inputs. Several studies have been conducted on this problem by introducing some general saturation function. However, study about whether saturation function was really best and the performance analysis when using the other functions, weren’t being done so much. Therefore, in this paper, several candidate functions for SMC are selected and control performance of candidate functions is analyzed. In the analysis, evaluation function based on the trade-off between slip suppression performance and chattering reduction performance is proposed. The analyses are conducted in several numerical simulations of slip suppression problem of EVs. Then, we can see that there is no difference of employed candidate functions in chattering reduction performance. On the other hand, in slip suppression performance, the saturation function is excellent overall. So, we conclude the saturation function is most suitable for slip suppression sliding mode control.Keywords: sliding mode control, chattering function, electric vehicle, slip suppression, performance analysis
Procedia PDF Downloads 3187163 Structural Properties, Natural Bond Orbital, Theory Functional Calculations (DFT), and Energies for Fluorous Compounds: C13H12F7ClN2O
Authors: Shahriar Ghammamy, Masomeh Shahsavary
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In this paper, the optimized geometries and frequencies of the stationary point and the minimum energy paths of C13H12F7ClN2O are calculated by using the DFT (B3LYP) methods with LANL2DZ basis sets. B3LYP/ LANL2DZ calculation results indicated that some selected bond length and bond angles values for the C13H12F7ClN2O.Keywords: C13H12F7ClN2O, vatural bond orbital, fluorous compounds, functional calculations
Procedia PDF Downloads 3297162 MP-SMC-I Method for Slip Suppression of Electric Vehicles under Braking
Authors: Tohru Kawabe
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In this paper, a new SMC (Sliding Mode Control) method with MP (Model Predictive Control) integral action for the slip suppression of EV (Electric Vehicle) under braking is proposed. The proposed method introduce the integral term with standard SMC gain , where the integral gain is optimized for each control period by the MPC algorithms. The aim of this method is to improve the safety and the stability of EVs under braking by controlling the wheel slip ratio. There also include numerical simulation results to demonstrate the effectiveness of the method.Keywords: sliding mode control, model predictive control, integral action, electric vehicle, slip suppression
Procedia PDF Downloads 5517161 A Study on the Improvement of the Bond Performance of Polypropylene Macro Fiber according to Longitudinal Shape Change
Authors: Sung-yong Choi, Woo-tai Jung, Young-hwan Park
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This study intends to improve the bond performance of the polypropylene fiber used as reinforcing fiber for concrete by changing its shape into double crimped type through the enhancement its fabrication process. The bond performance of such double crimped fiber is evaluated by applying the JCI SF-8 (dog-bone shape) testing method. The test results reveal that the double crimped fiber develops bond performance improved by more than 19% compared to the conventional crimped type fiber.Keywords: Bond, Polypropylene, fiber reinforcement, macro fiber, shape change
Procedia PDF Downloads 4537160 Unsteady MHD Thin Film Flow of a Third-Grade Fluid with Heat Transfer and Slip Boundary Condition Down an Inclined Plane
Authors: Y. M. Aiyesimi, G. T. Okedayo, O. W. Lawal
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An investigation is made for unsteady MHD thin film flow of a third grade fluid down an inclined plane with slip boundary condition. The non-linear partial differential equation governing the flow and heat transfer are evaluated numerically using computer software called Maple to obtain velocity and temperature profile. The effect of slip and other various physical parameter on both velocity and temperature profile obtained are studied through several graphs.Keywords: non-Newtonian fluid, MHD flow, third-grade fluid, Maple, slip boundary condition, heat transfer
Procedia PDF Downloads 4497159 Investigating the Difference in Stability of Various Isomeric Hydrogen Bonded Dimers
Authors: Mohamed Ayoub
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The structures and energetics of various isomeric hydrogen bonded dimers, such as (FH…OC, FH…CO), (FH…CNH, FH…NCH), (FH…N2O, FH…ON2), and (FH…NHCO, FH…OCNH) have been investigated using DFT B3LYP with aug-cc-pVTZ basis set and by natural bond orbital (NBO) analysis. For each isomeric pair we calculated: H-bond energy (ΔEB…H), charge-transfer (QCT), where B is atom bearing lone-pairs in CO, CNH, NCH, N2O, and NHCO, H-bond distances (RB…H), the elongation of HF bond (ΔRHF) and the red-shift of HF stretching frequency (ΔVHF). We conclude that the principle difference in the relative stability between each isomeric pair is attributed to distinctive interaction of carbon and oxygen lone pairs of CO, carbon and nitrogen lone-pairs of CNH and NCH, and nitrogen and oxygen lone pairs of N2O and NHCO into the unfilled antibond on HF (σ*HF).Keywords: charge transfer, computational chemistry, isomeric hydrogen bond, natural bond orbital
Procedia PDF Downloads 2357158 Obligation, the Shifting Nature of Physician-Patient Relationship, and the Basic Healthcare Reform in Mainland China
Authors: Jia Liu
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This article explores the shifting nature of physician-patient relationship in mainland China. Specifically, it takes the physician-patient relationship during the barefoot doctor program in 1968-1978, the marketization of healthcare services in 1978-2002, and the healthcare reform in 2003-2020 as three typical historical periods, illustrating how the nature of the physician-patient relationship has changed over time in mainland China. Drawing on recent jurisprudential literature that emphasizes the roles and functions done by and through obligation rather than right, it explores how the obligations of physicians and patients along with the implementation of informed consent, marketization of the healthcare system, and the basic healthcare reform have affected their relationship. One key feature of this article is that it analyzes the ways in which commodification and decommodification of healthcare have defined and in many different ways have determined the expectations and practices of physicians and patients, which illustrates how the trust between physicians and patients threatens to collapse and the bond between the citizen and the state fails to be firmly established in the mainland Chinese healthcare context. It also pays special attention to the role played by law and legal institutions—for instance, the implementation of informed consent and the liability law—in being complicit in facilitating the decoupling of the practices of physicians and patients from their ethical senses of obligation and undermining the bond (the trust relationship) between them.Keywords: healthcare, marketization, physician-patient relationship, sense of obligation
Procedia PDF Downloads 1347157 Effect of Boundary Condition on Granular Pressure of Gas-Solid Flow in a Rotating Drum
Authors: Rezwana Rahman
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Various simulations have been conducted to understand the particle's macroscopic behavior in the solid-gas multiphase flow in rotating drums in the past. In these studies, the particle-wall no-slip boundary condition was usually adopted. However, the non-slip boundary condition is rarely encountered in real systems. A little effort has been made to investigate the particle behavior at slip boundary conditions. The paper represents a study of the gas-solid flow in a horizontal rotating drum at a slip boundary wall condition. Two different sizes of particles with the same density have been considered. The Eulerian–Eulerian multiphase model with the kinetic theory of granular flow was used in the simulations. The granular pressure at the rolling flow regime with specularity coefficient 1 was examined and compared with that obtained based on the no-slip boundary condition. The results reveal that the profiles of granular pressure distribution on the transverse plane of the drum are similar for both boundary conditions. But, overall, compared with those for the no-slip boundary condition, the values of granular pressure for specularity coefficient 1 are larger for the larger particle and smaller for the smaller particle.Keywords: boundary condition, eulerian–eulerian, multiphase, specularity coefficient, transverse plane
Procedia PDF Downloads 2137156 Productivity Improvement in the Propeller Shaft Manufacturing Process
Authors: Won Jung
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In automotive, propeller shaft is the device for transferring power from engine to axle via transmission, and the slip yoke is one of the main parts in the component. Since the propeller shafts are subject to torsion and shear stress, they need to be strong enough to bear the stress. The purpose of this research is to improve the productivity of slip yoke for automotive propeller shaft. We present how to redesign the component that currently manufactured as a forged single body type. The research was focused on not only reducing processing time but insuring durability of the component simultaneously.Keywords: automotive, propeller shaft, productivity, durability, slip yoke
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