• Journal of Korean Society of Steel Construction
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• v.24 no.5
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• pp.605-612
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• 2012

A tension member that has a high-strength bolt fastened to a standard bolt hole increases structural resistance but causes problems from workability or economic perspectives. In this research, a total of 28 samples that have standard and over bolt holes as the tension member's high-strength bolted connection were made and a tension test was conducted. The change of strength of the connection has been confirmed by comparing the tension load of standard and over bolt hole samples obtained from the test results with the design strength due to net section and end distance. Samples made with over bolt holes had a lighter tension load than that of samples made with standard bolt holes, exceeded the design strength of present design standards, and although decrease in strength was inevitable due to the over bolt hole, their safety was satisfactory.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2B
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• pp.149-152
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• 2012

This study is carried out to analyze the design method and safety rate degree for IEC 61400-3, DNV-OS-J101, GL Wind, EUROCODE, AASHTO and domestic design standard used for offshore wind turbine foundation design. The findings will provide a design parameter for domestic offshore wind turbine foundation design. The design of the steel Support Structure of an offshore wind turbine can be based on either the Allowable Stress Design(ASD) approach or the Load and Resistance Factor Design(LRFD) approach. The design principles with the use of LRFD method are described with various limit states. A limit state is a condition beyond which a structure or part of a structure exceeds a specified design requirement. Design by the LRFD method is a design method by which the target component safety level is obtained by applying load and resistance factors to characteristic reference values of loads (load effects)and structural resistance. When the strength design of the steel Support Structure is based on the ASD approach, the design acceptance criteria are to be expressed in terms of appropriate basic allowable stresses in accordance with the requirements specified. After comparison an economics domestic offshore wind turbine foundation standard will be developed.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.41-47
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• 2010

For the enhancement of structural safety of thermally damaged reinforced concrete structure, rapid evaluation of damage in the structure is very important. This study addresses a simplified method which is equivalent to the standard fire curve (ISO 834) for the residual bond strength evaluation. In the proposed method, a exposure duration as well as the maximum temperature can be considered. For the comparisons with conventional methods, concrete properties obtained from the report of Daegu subway fire accident were referred and the results support the applicability of the proposed method in this study.

• Journal of Energy Engineering
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• v.29 no.3
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• pp.91-96
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• 2020

For the anchor bolts and brackets that fix the stone wall, which is an external finishing material, it is necessary to maintain the performance required for the mechanical structure from the initial design stage and secure high durability. For this, the design and safety evaluation in consideration of the load conditions are necessary, so the structural analysis applying the finite element analysis technique was performed as a method to verify durability. As a result of structural analysis for various shapes for optimal design, a reinforcing structure was added to alleviate the maximum stress generated at the rear part of the bracket in contact with the bolt. In addition, a reinforcing plate was additionally attached to the bracket to relieve the stress concentration of the L-shaped bracket to make the stress distribution uniform, so that the safety factor satisfies the standard conditions. In addition, the fatigue life analysis by cyclic load was performed, and the fatigue safety factor was analyzed. As a result, the durability was obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1045-1053
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• 2013

Boat or yacht hull has been built mainly by FRP composite materials. FRP boat hull manufacturing begins to be restricted after the year 2000 under international regulation on ocean environment safety. The alternative of FRP has been proposed by many boat builders and high strength aluminium is considered as its standard material. But high strength aluminium is very expensive as boat hull material. In this study, boat hull is considered to be built by high density polyethylene and its structural strength is estimated by longitudinal strength test method on small craft. Tensile strength of polyethylene boat hull material is higher than that of FRP boat hull material. But safety factor of polyethylene boat hull is more than that of FRP boat hull. These study results indicate structural integrity and quality control of polyethylene boat is better than those of FRP boat.

• Computational Structural Engineering
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• v.10 no.2
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• pp.189-201
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• 1997

A number of standard type of steel-box pedestrian bridges are constructed in th metropolitan high way or heavy traffic urban area. Although it has the advantage of speedy construction because of its simple structural form and prefabricated erection method, it has been reported that many of these bridges are deteriorated or damaged and thus are in the state such that it would give unsafe and uncomfortable feeling to pedestrians. In the paper, for the realistic assessment of safety and load carrying capacity of deteriorated and/or damaged steel box pedestrian bridges, an interactive non-linear limit state model is formulated based on the von Mises' combined stress yield criterion. It has been demonstrated that the proposed model is effective for the reliability-based safety assessment and load carrying capacity evaluation of steel-box pedestrian bridges. In addition, this study suggests an effective and practical field load test method for pedestrian bridges.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.2
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• pp.143-150
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• 2001

원자력발전소의 1차 계통에서 오염된 장비들을 취급이 용이하고 안전하게 운반하기 위한 운반용기는 내부의 방사성 물질에 대한 방사능 평가에 의하여 방사성물질 A형 운반용기로 분류된다. 방사성물질 A형 운반용기는 IAEA Safety Standard Series No. ST-1 및 국내 원자력법 등 관련규정의 기술기준을 만족하여야 하는데, 운반용기는 중량에 따라 0.3∼1.2m의 높이에서 소성이 일어나지 않는 단단한 바닥면으로 가장 심각한 손상을 주는 방향으로 낙하시키는 정상운반조건(normal transport conditions)에 대하여 구조적 건전성을 유지하여야 한다. 여기서는 ABAQUS/Explicit 코드를 이용하여 컨테이너형태의 A형 운반용기에 대하여 최대손상이 야기되는 0.9m 경사낙하조건에 대한 3차원 충격해석을 수행하고 구조적 건전성을 평가하였는데, 운반용기는 경사낙하시 코너피팅(corner fitting)의 분쇄(crush)에 의하여 대부분의 충격을 흡수하였으며 운반용기의 격납경계는 구조적 건전성을 유지하였다.

• Journal of Power System Engineering
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• v.12 no.6
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• pp.24-28
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• 2008

It expects demand of ships which equipped with JIB crane growth to continue. However, demand of JIB crane is increased, domestic shipment company imitated the design of Europe and Japan. And we need to develop the functional system of the JIB crane and modernize it. We need to find the optimum luffing angle for saving energy when JIB crane works. This study analyzed buckling load of JIB and reaction force of support point and stress of JIB according to the luffing angle through finite element analysis when JIB crane loads 40 ton weight. And this study considered the safety factor 1.8 of material. Every design condition was KS A1627 standard. This study used ANSYS 10.0.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.2
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• pp.11-18
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• 2016

The collapsing accidents of greenhouse frames have been increased yearly due to strong wind and heavy snow, but as it was, there were few studies about the structural safety of greenhouses. Therefore, this study was carried out to develop the stress tolerant structural frame systems in built-up greenhouses. The vertical loading experiment of developed scale models were implemented and the developed types of models were simulated by 3-D analysis program in this study. These types of models, which are existing type and honeycomb type, in arch and standard style frames were classified. As a result of this study, it was verified that the honeycomb type model of arch style frame is better than the existing type model of it in stress resistance against snow load and wind load.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.364-369
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• 2002

The purpose of this paper is to introduce the concept design and the structural strength of the double-deck rolling stock vehicle. Aluminum is very useful material for the carbody structure due to its characteristic of light weight. Large alumillum extrusion profiles(panels) have toe of merits such as easy production of complicated shapes, reduction of welding and cutting lines, and cutting down the labor cost. AED type is being applied to the standard EMUs and the EMUs Kwangju subway in Korea. Light material recommended the double-deck rolling stock vehicle because the center of gravity of the train is higher and its weight is heavier than those of the normal vehicle. So we applied the technology of the large aluminum extrusion profiles(panels) to the double-deck vehicle. We performed the structural strength analysis and examined its safety.