• Transactions of Materials Processing
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• v.23 no.5
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• pp.289-296
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• 2014

Uniaxial tensile tests were conducted to accurately evaluate the in-plane mechanical properties of fiber metal laminates (FMLs). The FMLs in the current study are comprised of a layer of self-reinforced polypropylene (SRPP) sandwiched between two layers of aluminum alloy 5052-H34. The nonlinear tensile behavior of the FMLs under in-plane loading conditions was investigated using both numerical simulations and a theoretical analysis. The numerical simulation was based on finite element modeling using the ABAQUS/Explicit code and the theoretical constitutive model was based on the volume fraction approach using the rule of mixture and a modification of the classical lamination theory, which incorporates the elastic-plastic behavior of the aluminum alloy and the SRPP. The simulations and the model are used to predict the inplane mechanical properties such as stress-strain response and deformation behavior of the FMLs. In addition, a post-stretching process is used to reduce the thermal residual stresses before uniaxial tensile testing of the FMLs. Through comparison of both the numerical simulations and the theoretical analysis with the experimental results, it is concluded that the numerical simulation model and the theoretical approach can describe with sufficient accuracy the actual tensile stress-strain behavior of the FMLs.

• Journal of Ocean Engineering and Technology
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• v.1 no.2
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• pp.113-122
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• 1987

Ships and offshore strrctures are exposed to the corrosive surroundings, and the extablishment of the design criteria and the elucidation on the influence by this environment are requested to maintain the safety and to demonstrate the function of the structure. In this paper, the fatigue-crack-growth behavior on the compact tension specimens of quenched, tempered HT80 grade steels and RA36 high tensile steels having a single edge fatigue cracked notch respectively, were investigated under the repeated tensile stress with constant stroke in sea water for the welded parts by shielded metal arc welding. Main results obtained are summerized as follows; 1. The fatigue-crack-growth rates da/dN in sea water appeared to be greater behavior than those in air environment at the same stress intensisy factor range $\DeltaK$. 2. The correlation data of da/dN$\DeltaK$ of the two kinds of high tensile steels in sea water showed no great difference, however, the correlation data of da/dN$\DeltaK/\sigma_y$($\sigma_y$ stands for yield strength of the material) showed that the fatigue-crack-growth behavior of RA36 plate is affected by active path corrosion(APC) mechanism, while that of HT80 grade plate is mainly affected by hydrogen embrittlement mechanism.

• Magazine of the Korea Concrete Institute
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• v.7 no.5
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• pp.145-154
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• 1995

Concrete has two different failure mechanisms : compressive crushing and tensile cracking. Concrete models should use the two different failure criteria to analyze the inelastic behavior of concrete including multiaxial crushing and tensile cracking. Concrete models used in this study are based on plasticity with multiple failure criteria of compressive crushing and tensile cracking. For tensile cracking behavior, two different plasticity models are investigated. The* ,e are rotating-crack and fixed-crack plasticity models, classified according to idealization of crack 0rientat:ions. The material models simplify inelastic behavior of concrete for plane stress problenls. The material models are used for the finite element anlaysis. Analytical results are compared with several experiments of reinforced concrete member. The advantages and disadva.ntages of rotating-crack and fixed -crack plasticity models are discussed.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.260-267
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• 2021

The purpose of this study was to experimentally investigate the effects of curing methods on the compressive strength and tensile behavior of alkali-activated slag-based fiber-reinforced composite with a water-to-binder ratio of 15%. Three kinds of mixtures according to the curing conditions were prepared and compressive strength and tension tests were performed. Test results showed that the compressive strength and the first cracking strength of composites decreased when high temperature curing and air curing were adopted, while tensile strain capacity of composites increased. It was also observed that crack spacing and crack width of composites decreased by applying high temperature and air curing.

• Advances in concrete construction
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• v.11 no.3
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• pp.261-270
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• 2021

In this study, a new understanding is presented on the microcracking behavior of high strength concrete (HSC) with steel fiber addition having prior compressive loading history. Microcracking behavior at critical stress (σcr) region, using seven fiber addition volume of 0.5, 0.75, 1.0, 1.25, 1.5, 1.75, and 2.0% was evaluated, at two aspect ratios (60 and 75). The specimens were loaded up to a specified compressive stress levels (0.70fc-0.96fc), and subsequently subjected to split tensile tests. This was followed by microscopic analyses afterwards. Four compressive stress levels as percentage of fc were selected according to the linearity end point based on stress-time (σ-t) diagram under uniaxial compression. It was seen that pre-compression has an effect on the linearity end point as well as fiber addition where it lies within 85-91% of fc. Tensile strength gain was observed in some cases with respect to the 'maiden' tensile strength as oppose to tensile strength loss due to the fiber addition with teething effect. Aggregate cracking was the dominant failure mode instead of bond cracks due to improved matrix quality. The presence of the steel fiber improved the extensive failure pattern of cracks where it changes from 'macrocracks' to a branched network of microcracks especially at higher fiber dosages. The applied pre-compression resulted in hardening effect, but the cracking process is similar to that in concrete without fiber addition.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.230-233
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• 2006

In this study, the effects of residual stress induced by plastic injection molding process on the tensile behavior of plastic tensile test specimen were investigated. To manufacture plastic tensile test specimens, an injection mold based on the international standard system was designed and made. Cavity pressure and temperature sensors were installed inside of the presented mold to monitor pressure and temperature values during the cycle of injection molding. Injection molding simulation was performed with the same condition of experiment and linear structural tensile analysis was also performed with the initial condition of the residual stress. It was shown that the residual stress induced by injection molding has an effect on the experiment of tensile test and linear structural tensile simulation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.464-466
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• 2009

This study tried to examine the suitability of strip casting process such as PFC (Planar Flow Casting) method for soldering Au-Sn strip. The effect of heat treatment on the tensile behavior and mechanical properties of an Au-Sn strip was investigated through tensile test, micro hardness test, X-ray diffraction (XRD), SEM, and TEM observations. It was apparent that 20-mm width Au-Sn strip could be well produced by using planar flow casting process. Tensile results showed that tensile strength increased from 338.3MPa to 310MPa and plastic strain improved from 0% to 1.5% with heat treatment ($170^{\circ}C$/70 hrs.). The microstructure of Au-Sn strip mainly consisted of two phases; $Au_5Sn(\zeta)$ and AuSn($\sigma$). It was also found that inhomogeneous amorphous local structure continuously changed to the homogeneous two phases microstructure with heat treatment. The fractographical observation after tensile test indicated the cleavage fracture mode of as-casted Au-Sn strip. On the other hand, the heat treated Au-Sn strip showed that fracture propagated along interface between brittle AuSn and ductile $Au_5Sn$ phases. The deformation behavior of strip casted Au-Sn alloy with microstructural evolution and the improve method for ductility of this alloy was also suggested.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.4
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• pp.91-99
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• 2020

Post-installed anchors were widely used due to its workable benefits. Regarding the resistance performance of anchors, the critical edge distance is presented to minimize the impact of concrete splitting. In the case of actual anchors, however, it is difficult to obtain the ideal edge distance. The purpose of this study is to identify resistance performance and behavior characteristics that contain complex elements such as concrete crack occurring under tensile load. Tensile tests were conducted based on the standard method. Failure shape and the resistance characteristics that do not have the critical edge distance were derived by tensile load. Parametric analysis according to the boundary condition was performed to simulate the actual tensile behavior, through a nonlinear finite element model based on the specimen. Consequently therefore, verifying analysis results the resistance mechanism can be applied through boundary conditions.

• Journal of the Korea Concrete Institute
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• v.13 no.4
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• pp.321-328
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• 2001

This paper presents the tensile behavior of stud connections installed between reinforced concrete and steel members. Eight specimens are tested to verify the factors influencing the tensile behavior of the connection. Major variables considered in the test are the reinforcement ratios of concrete member and connection details. Test results indicate that the reinforcing bars near stud bolts contribute to the increase of the tensile strength of the member as well as to the reduction of brittle failure. It is shown that C-type or U-type connection has relatively high ductility. From the evaluation on the tensile strength of test results including those of peformed by previous researchers, it was shown CCD (Concrete Capacity Design) method overestimated the strength. In this paper, the reduction factor of 0.75 ø instead of ø is suggested for design purpose of the stud connection.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.3
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• pp.211-217
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• 2012

In this paper, experimental tests and theoretical studies were carried out to evaluate the tensile behavior of the sprayed FRP composite with chopped glass fiber. For this, a series of tensile strength tests with various strain rates were conducted on the specimens of the matrix and sprayed FRP composite. Sprayed FRP composite contained chopped glass fibers with fiber length of 15mm and a specific volume fraction of fibers of 25 %. An inverse simulation was conducted to simulate the strain rate sensitivity based on the present experimental data of the epoxy resin. The simulated viscosity value is adapted to the micromechanics-based viscoelastic damage model(Yang et al., 2012), and the overall tensile behavior of sprayed FRP composites is predicted. It was seen from the comparative study between present experimental data and predication results that the proposed methodology can be used to predict the viscoelastic behavior of the sprayed FRP composite.