• Structural Engineering and Mechanics
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• v.16 no.1
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• pp.63-81
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• 2003

This paper describes experimental and theoretical investigations on the behaviour of thin walled composite (TWC) filled columns under eccentric loading conditions. Details of the experimental investigation including description of the test columns, testing arrangements, failure modes, strain characteristics, load-deformation responses and effects of various geometric and material parameters are presented. The current paper also introduces the use and effect of lightweight Volcanic Pumice Concrete (VPC) in TWC columns. Analytical models for the design of columns under eccentric loading conditions have been developed taking into consideration the effect of confined concrete. The performance of design equations is validated through experimental results. The proposed design models are found to produce better results compared with available design procedures and Code based formulations. A computer program is developed to generate the interaction diagrams based on the proposed design equations that can be used for design purposes.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.159-165
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• 2003

To Recently, the buckling is easy to happen a thin plate and High Tensile Steel is used at the structure so that it is wide. Especially, the buckling is becoming important design criteria in the ship structure to use especially the High Tensile Steel. Consequently, it is important that we grasp the conduct after the buckling behaviour accurately at the stability of the body of ship structure. In this study, examined closely about conduct and secondary buckling after initial buckling of thin plate structure which receive compressive load according to various kinds aspect ratio under simply supported condition that make by buckling formula in each payment in advance nile to place which is representative construction of hull. Analysis method is F.E.M by ANSYS and complicated nonlinear behaviour to analyze such as secondary buckling.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.133-134
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• 2006

In contrast to paints, the surface appearance of adhesive materials is of minor importance, because the adhesive is invisible between the two substrates. Therefore, the rheological properties needed to apply an adhesive dispersion by spray coating can be quite different. The influence of three different kinds of thickeners on the spraying behaviour of polyurethane adhesive dispersions was investigated. The associative thickener showed only minor changes, whereas the higher molecular weight soluble thickeners dramatically changed the spraying angle and the amount of overspray. Determination of the elongational viscosity by means of the CaBER rheometer proved to be of limited use for thickened dispersions.

• Steel and Composite Structures
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• v.2 no.5
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• pp.355-378
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• 2002

Use of composite steel construction with precast hollow core slabs is now popular in the UK, but the present knowledge in shear capacity of the headed shear studs for this type of composite construction is very limited. Currently, all the information is based on the results obtained from experimental push-off tests. A finite element model to simulate the behaviour of headed stud shear connection in composite beam with precast hollow core slabs is described. The model is based on finite element method and takes into account the linear and non-linear behaviour of all the materials. The model has been validated against the test results, for which the accuracy of the model used is demonstrated. Parametric studies showing the effect of the change in transverse gap size, transverse reinforcement diameter and in-situ concrete strength on the shear connection capacity are presented.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.585-590
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• 1999

There is still a lack of knowledge and modelling relating to shear behaviour in reinforced concrete beams. The reason is that shear loading leads to complicated physical mecanisms, such as interlock action, dowel action, etc. Therefore, It is difficult that we make the ideal model of shear behaviour, while Truss model theory has been made good use of shear design because of simplicity and reasonableness. In this study, 6 T-type reinforced concrete beams were designed and made based on the two truss models, i.e, the plasticity truss model and the compatibility truss model, to observe shear strength of concrete and stress distribution of stirrups. 6 beams test pieces were tested with the following testing parameters. 1) specified concrete strength ; 270kg/$\textrm{cm}^2$, 400kg/$\textrm{cm}^2$ 2) with and without the steel fiber.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.496-503
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• 2003

Recently, the buckling is easy to happen a thin plate and High Tensile Steel is used at the structure so that it is wide. Especially, the buckling is becoming important design criteria in the ship structure to use especially the High Tensile Steel. Consequently, it is important that we grasp the conduct after the buckling behaviour accurately at the stability of the body of ship structure. In this study, examined closely about conduct and secondary buckling after initial buckling of thin plate structure which receive compressive load according to various kinds aspect ratio under simply supported condition that make by buckling formula in each payment in advance rule to place which is representative construction of hull. Analysis method is F.E.M by ANSYS and complicated nonlinear behaviour to analyze such as secondary buckling.

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.358-365
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• 2000

For the general case of loading conditions and boundary conditions, it is very difficult to obtain closed form solutions for buckling loads and natural frequencies of thin-walled structures because its behaviour is very complex due to the coupling effect of bending and torsional behaviour. In consequence, most of previous finite element formulations are introduce approximate displacement fields to use shape functions as Hermitian polynomials, and so on. The Purpose of this study is to presents a consistent derivation of exact dynamic stiffness matrices of thin-walled straight beams, to be used ill tile free vibration analysis, in which almost types of boundary conditions are exist An exact dynamic element stiffness matrix is established from governing equations for a uniform beam element of nonsymmetric thin-walled cross section. This numerical technique is accomplished via a generalized linear eigenvalue problem by introducing 14 displacement parameters and a system of linear algebraic equations with complex matrices. The natural frequency is evaluated for the thin-walled straight beam structure, and the results are compared with analytic solutions in order to verify the accuracy of this study.

• 한국전산유체공학회:학술대회논문집
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• 1998.05a
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• pp.156-161
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• 1998

This describes a numerical method for predicting the incompressible unsteady laminar three-dimensional flows of fluid behaviour with free-surface. The elliptic differential equations governing the flows have been linearized by means of finite-difference approximations, and the resulting equations have been solved via a fully-implicit iterative method. The free-surface is defined by the motion of a set of marker particles and interface behaviour was investigated by way of a 'Lagrangian' technique. Using the GALA concept of Spalding, the conventional mass continuity equation is modified to form a volumetric or bulk-continuity equation. The use of this bulk-continuity relation allows the hydrodynamic variables to be computed over the entire flow domain including both liquid and gas regions. Thus, the free-surface boundary conditions are imposed implicitly and the problem formulation is greatly simplified. The numerical procedure is validated by comparing the predicted results of a periodic standing waves problems with analytic solutions or experimental results from the literature. The results show that this numerical method produces accurate and physically realistic predictions of three-dimensional free-surface flows.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.3
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• pp.194-201
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• 1997

Recently with the rapid development in the industries such as an iron mill and chemical plants, these are enlarged by the use of the piping. This piping was encountered the stress corrosion cracking(SCC) because of stress by water pressure and residual stress of welding etc. under industrial water. In this paper, the behaviour of stress corrosion cracking on the weld zone of steel pipe piping water(SPPW) were investigated according to pre-heat before welding in natural seawater(specific resistance : 25$\Omega$-cm). The main results obtained are as follows :1) The stress corrosion cracking for SPPW and SB 41 is most ready to propagate in heat affected zone of weldment. 2) The SCC sensitivity of SPPW on weldment is more susceptible than that of SB 41. 3) The stress corrosion cracking growth of heat affected zone is delayed by the preheat and dry of base metal and electrode before welding.

• Water for future
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• v.9 no.1
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• pp.70-80
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• 1976

The efficient breakwater design requires a knowledge of the behaviour of the waves passing the breakwater. Wave Diffraction is an important factor and phenomeon in this behaviour. The diffraction ocean waves entering a gap in a breakwater normal to the incident wave direction in water of uniform depth has been investigated, applying a solution previously given in the author's paper, based on the theory of light diffraction by Sommerfeld. The wave profiles and heights on both the leeward side of the breakwater and the gap side have been studied and summarized in the form of diagrams with diffraction coefficients in range of x/L, y/L 0∼100, b/L=0.5∼12, with some extension of the diagrams made previously. The results of the theoretical approaches have not been experimentally verified. The theory ad computation methods with computer program in Fortran IV developed in this study make an efficient use for estimating the diffraction about a breakwater gap.