• Journal of the Korean Society of Hazard Mitigation
• /
• v.2 no.3 s.6
• /
• pp.119-125
• /
• 2002

The objective of this study is to evaluate elastic modulus of bridge-axis direction for optimum structure system in the cable-stayed bridge design. In numerical example of this study, a slight change in axis direction elastic modulus causes major modifications of the bridge characteristics when it is $1\times10^4$ tonf/m/bearing or less. Therefore, the elastic modulus was set at this lower limit of $1\times10^4$ tonf/m/bearing where the strength of the entire bridge system is still determined by girder strength and the entire system is insensitive to variations in elastic modulus. Besides, cable-stayed bridge with freely supported girders have slightly longer vibration periods in the horizontal direction for earthquake forces.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.2
• /
• pp.154-161
• /
• 2003

The effects of specimen geometry, and loading conditions on the J-integral fur CCT (center cracked tension) specimens are investigated by using FEM. It is found that the J-integral tends to decrease according to the parallel tensile loading to crack line. Furthermore, it is verified that the compressive parallel loading to crack line is likely to increase the J-integral. A stress ratio of length to width of the center CCT specimen is confirmed to affect the J-integral significantly.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 1997.04a
• /
• pp.114-120
• /
• 1997

원자력공사에 관련된 장치와 부속 기기를 설계 및 제작 또는 설치하려면 ASME에서 인증하는 자격이 필요하고, 자격을 취득하거나 갱신하기 위하여 시설, 품질보증 프로그램, 설계 및 제작능력등을 ASME 위원회의 실사를 받아야 한다. 이를 위한 일련의 과정 중에서 설계능력을 증명할 수 있는 설계해석 보고서를 제출하여야 하며 이를 위하여 현대중공업이 설계한 Chiler Surge Vessel의 설계조건 및 하중 및 하중조합에 대하여 Design Report를 작성하였으며, ASME Code의 요구조건을 모두 만족하는 것으로 평가되었다.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.30 no.4
• /
• pp.358-364
• /
• 2024

Type A carrier structures that support blocks or equipment gradually deform over time with load changes, reducing the area in contact with the block and changing the load pattern from distributed to concentrated during construction work in the shipyard. This phenomenon has the potential to misrepresent actual service loads. In particular, A carriers are often used by small manufacturers, who often do not have specialized engineering capabilities, necessitating the development of a method for easy calculation of carrier safe working load. This study proposes a quick evaluation method for the long-term safe working load of Type A carriers, to predict the plastic deformation and safety issues resulting from changes in load distribution. Based on the results of finite element analysis (beam and shell modeling) of the centralized load, beam-theory was modified to propose a method for determining the distributed load conditions of the A-carrier. In beam modeling, the theoretical value was multiplied by a correction factor of 0.73 for concentrated loads and 0.69 for distributed loads to obtain a safe working load. For shell modeling, a correction factor of 0.75 can be used for concentrated loads and 0.69 for distributed loads. This study can serve as a basis for improving the safety of shipbuilding, enabling quick and effective decisions for determining safe working loads in actual working environments.

• Journal of the Korean Institute of Gas
• /
• v.13 no.1
• /
• pp.1-8
• /
• 2009

Recently, the vibration of underground structure due to high speed railway loads has been increased substantially as compared with middle and slow speed. The buried gas pipelines under continuous impact forces and repeated loading are more influenced by the vibrational loads than another pipelines. However, the static analysis was not enough to allow for the effect of vibrations because it uses impact factors for the design or analysis process. In this study, characteristics of Pipelines was quantitatively estimated through each conditions of soil covers and train speed, and the new vibration prediction is presented about the vibrational velocity.

• Fire Science and Engineering
• /
• v.21 no.1 s.65
• /
• pp.51-59
• /
• 2007

The purpose of this study is analyzing the fire behavior according to the fire load for G underground shopping mall located in Daegu city. when predict fire behavior, fire load and ventilation coefficient are important factor who dominate fire temperature or fire continuance time. Therefore, size of unit room, opening size and inflammable investigated on the field. Fire load calculated using unit calorific value by each material of inflammable that investigate. And reduction model experimented fire load about 6 models with variable. Fire behavior analyzed by heat flows of inside space that temperature rise and temperature change by time of fire source.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.33 no.2
• /
• pp.39-45
• /
• 2005

The aim of this research is to predict the thickness and loading noise of the round-tip shaped Hartzell propeller currently used in the general aviation aircraft. Before implementing the noise analysis, the pressure distribution on the propeller was obtained by using the free wake panel method and unsteady Bernoulli's equation. The noise signal at observer position can be obtained by using the FW-H equation. The noise prediction results for the propeller indicates that the thickness noise has s symmetric directivity pattern with respect to the tip path plane, while the noise due to loading shows higher noise directivity toward downstream than the upstream direction from the rotor plane. The loading noise is dominant rather than the thickness noise in normal operating condition.

• The Journal of the Convergence on Culture Technology
• /
• v.5 no.2
• /
• pp.355-360
• /
• 2019

In this study, the structural stability of the railway level crossing system using rubber panel for high speed lines was investigated by applying the specification for wind load conditions (Train gust) of high speed train (300km/h and 360km/h). A finite element analysis using three-dimensional modeling was carried out by applying the field conditions that was installed with the complicated configuration of the rubber plate panel system. As a result of this study, the structural stability of the rubber plate panel system for high speed train gust was analytically verified.

• Composites Research
• /
• v.22 no.1
• /
• pp.1-8
• /
• 2009

In this paper low-velocity impact response and damage of composite laminates is analytically investigated. A modified displacement field of plate considering initially loaded in-plane strain is proposed. From the displacement field a finite element equation on structural behavior of composite laminate is newly induced and a computational program is coded. Numerical results using the FEM code is compared with the numerical ones from reference. Additional numerical analysis is performed on another impact condition and effect of initial in-plane load is reviewed. Potential delamination damage area in the first inter-ply surface from bottom of laminate is approximated and effect of initial in-plane load and impact condition is also reviewed.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.5
• /
• pp.13-22
• /
• 2018

In this study, a governing differential equation for the bending problem of orthotropic rectangular plate is drived. It's exact solution for various boundary conditions is presented. This solution follows traditional method like Navier's solution or Levy's solution that transforms the governing differential equation into an algebraic equation by using trigonometric series. To obtain a solution by Levy's method, it is required that two opposite edges of the plate be simply supported. And the boundary conditions, for which the Navier's method is applicable, are simply supported edge at all edges. In this study, it overcomes the limitations of the previous Navier's and Levy's methods.This solution is applicable for any combination of boundary conditions with simply supported edge and clamped edge in x, y direction. The plate could be subjected to uniform, partially uniform, and line loads. The advantage of the solution is that it is the exact solution as well as it overcomes the limitations of the previous Navier's and Levy's methods. Calculations are presented for orthotropic plates with nonsymmetric boundary conditions. Comparisons between the result of this paper and the result of Navier, Levy and Szilard solutions are made for the isotropic plates. The deflections were in excellent agreement.