• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.477-482
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• 2001

This paper is to study the effect of longitudinal reinforcement ratios and axial deformation on the frame analysis in reinforced concrete(RC) columns and to investigate the effect of confined concrete core, the length-width ratio and longitudinal steel ratios on frame analysis in Concrete-Filled steel Tubular(CFT) columns. An equation if derived to evaluate the modulus of elasticity for core concrete. The 34 reference data have been collected for the purpose and are processed by the mean of a multiple regression analysis technique. The equation and longitudinal reinforcement ratios was applied to RC columns for structural analysis. Then, the difference of beam moment was identified. In general, the results of analysis was indicated reasonable differences in beam moment, in case of longitudinal reinforcement ratios applied to RC columns when compared with the plain concrete columns. In CFT columns the equation was also applied in order to the effect of confined concrete core on structural analysis. Beam moment was increased as volumetric ratio of lateral steel was decreased. The effect of longitudinal steel ratios was investigated in CFT columns and was confirmed beam moment variety. The result was appeared reasonable difference in beam moment as longitudinal steel was increased.

• Journal of the Korean Institute of Navigation
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• v.8 no.2
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• pp.43-50
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• 1984

When the static load is applied to the ship's hull the deflection due to the bending moment from longitudinal direction has not been considered in the usual calculation of maximum bending moment. In fact, however, the deflection of ship's hull must be affected by the above-stated bending moment, and in this case the value of the maximum bending moment would be lessened in comparision with the result of usual calculation. In this paper, the author at first calculated the difference between the two values in case of rectangular barge, and suggested a practical criterion of longitudinal strength.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.443-450
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• 2014

In this study, we have discussed about the effect of hydrofoil arrangement and longitudinal moment characteristic on longitudinal motion stability of fully-submerged hydrofoil by the experiment of tandem hydrofoil model. First of all, tandem hydrofoil model that has canard wing arrangement has been made and characteristics of lift force and drag force by performing the lift force and drag force measuring experiment has also been estimated. Besides, tandem hydrofoil model's wing arrangement which has the initial stability and self stability of longitudinal motion has also been determined. In longitudinal stability experiment of tandem hydrofoil model, the motion characteristic of pitch and heave and the longitudinal stability of foil borne condition by variation of self stability of longitudinal moment and longitudinal distance are estimated. The result from the experiment and it's important conclusion can be described as below; Increase the self stability for longitudinal moment, the higher self stability for pitch motions in a constant pitch angles. By increasing the self stability for longitudinal moment, the range of fluctuation of pitch motion and heave motion for pitch angle also will change relatively small and longitudinal stability is excellent. Lastly, when the lift force of hydrofoil is remain constants, we can conclude that securing the enough self stability for longitudinal moment is essential for stable foil borne condition of tandem hydrofoil.

• Structural Engineering and Mechanics
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• v.52 no.4
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• pp.843-855
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• 2014

Concrete infill and reinforcement are one of the most well-known strengthening methods of structural elements. This study investigated flexural performance of concrete infill composite PHC pile (ICP pile) reinforced by infill concrete and longitudinal rebars in hollow PHC pile. A total four series of pile specimens were tested by four points bending method under simply supported conditions and investigated bending moment experimentally and analytically. From the test results, it was found that although reinforcement of infilled concrete on the pure bending moment of PHC pile was negligible, reinforcement of PHC pile using infilled concrete and longitudinal rebars increase the maximum bending moment with range from 1.95 to 2.31 times than that of conventional PHC pile. The error of bending moment between experimental results and predicted results by nonlinear sectional analysis on the basis of the conventional layered sectional approach was in the range of -2.54 % to 2.80 %. The axial compression and moment interaction analysis for ICP piles shows more significant strengthening effects of infilled concrete and longitudinal rebars.

• Journal of Welding and Joining
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• v.23 no.3
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• pp.47-53
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• 2005

Longitudinal deformation is produced by fillet welding during the fabrication of built-up beams and decreases productivity and quality because it needs an extra correcting process. The deformation is caused by welding moment, which is the value multiplied the welding shrinking farce by the distance from the neutral axis. This welding moment can be offset by generating a moment in the same magnitude and in an opposite direction by induction heating. The location and quantity of the induction heating are decided via experiments and simple equations. This study, first, clarifies the creation mechanism of the longitudinal deformation with FEM analysis. Then, we presents the preventive method of this deformation by induction heating basing on the mechanism and verifies its validity through analysis and experiments.

• International Journal of Korean Welding Society
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• v.3 no.2
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• pp.7-14
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• 2003

During the manufacture of a ship, longitudinal deformation is produced by fillet welding on the Built­Up beam used to improve the longitudinal strength of a ship. This deformation needs a correcting process separate from a manufacture process and decreases productivity and quality. This deformation is caused by welding moment, which is the value multiplied the shrinking force due to welding by the distance from the neutral axis on a cross section of Built­Up beam. This deformation can be offset by generating a moment which is the same magnitude with and is located in an opposite direction to the welding moment on web plate by induction heating. Accordingly, this study clarifies the creation mechanism of the longitudinal deformation on Built­Up beam with FEM analysis and presents the preventative method of this deformation by induction heating basing the mechanism and verifies its validity through analysis and experiments. The induction heating used here is performed by deciding its location and quantity with experiments and simple equations and by applying them to a real structure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.3
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• pp.17-24
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• 1992

It would be much effective that single column type pier is used in concrete slab bridges rather than ${\Pi}$ or gravity type pire is used. To determine the longitudinal benging moment in concrete slab bridges supported by single column type piers, the concept of effective width is applied. By elastic plate theory cooperated with finite element method, the distribution of the longitudinal moment of the slab supported by single column type piers is studied. The main variables are span, width. thickness of the slab, and column section size. The analytical results obtained are summarized and analysed to evaluate the maximum longitudinal negative moment, then a simplified method for calculating the longitudinal moment is proposed.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1992.10a
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• pp.73-78
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• 1992

It would be much effective that single column type pier is used in concrete slab bridges rather than gravity type pier is used. To determine the longitudinal bonging moment in concrete slab bridges supported by single column type piers, the concept of effective width is applied. By elastic plate theory cooperated with finite element method, the distribution of the longitudinal moment of the slab supported by single column type piers is studied. The main variables are span, width, and thickness of the slab and column section size. Then the analytical results obtained are summarized and analysed to evaluate the maximum longitudinal negative moment by simple beam analysis.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.816-825
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• 2002

During the manufacture of a ship, longitudinal deformation is produced by fillet welding on the BuiltUp beam used to improve the longitudinal strength of a ship. This deformation needs a correcting process separate from a manufacture process and decreases productivity and quality. This deformation is caused by welding moment, which is the value multiplied the shrinking force due to welding by the distance from the neutral axis on a cross section of Built-Up beam. This deformation can be offset by generating a moment which is the same magnitude with and is located in an opposite direction to the welding moment on web plate by induction heating. Accordingly, this study clarifies the creation mechanism of the longitudinal deformation on Built-Up beam with FEM analysis and presents the preventative method of this deformation by induction heating basing the mechanism and verifies its validity through analysis and experiments. The induction heating used here is performed by deciding its location and quantity with experiments and simple equations and by applying them to areal structure.

• International Journal of Automotive Technology
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• v.7 no.7
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• pp.803-812
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• 2006

In order to reduce the negative effects of dynamic coupling among vehicle subsystems and improve the handling performance of vehicle under severe driving conditions, a vehicle chassis control integration approach based on a main-loop and servo-loop structure is proposed. In the main-loop, in order to achieve satisfactory longitudinal, lateral and yaw response, a sliding mode controller is used to calculate the desired longitudinal, lateral forces and yaw moment of the vehicle; and in the servo-loop, a nonlinear optimizing method is adopted to compute the optimal control inputs, i.e. wheel control torques and active steering angles, and thus distributes the forces and moment to four tire/road contact patches. Simulation results indicate that significant improvement in vehicle handling and stability can be expected from the proposed chassis control integration.