• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.1-9
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• 2018

The development of new technology and process in industrial Plant which builds integrated structures, facilities and systems. Has become a key element for strengthening its competitiveness. Although domestic industrial Plant has demonstrated excellence in technology with a persistent increase in order quantity and orders received, the technology gap between countries has narrowed due to global construction trend. Therefore, it is necessary to develop new technology that could help overcome constraints and limitations of the current one to follow the trend in the age of unlimited competition. This study has focused on assembly technology of Pipe-rack joint connection in an effort to strengthen technological competitiveness in industrial Plant. Through an analysis of earlier studies on Pipe-rack and a coMParative analysis of strengths and weaknesses of current assembly technology of it, a new design plan has been made to improve it efficiently. In doing this, standards for design factors of both structural and performance features have been drawn, and value of stress, strain, moment and rotation has been calculated using finite element analysis. As a result, installation technology of modular type Pipe-rack, which has not been developed in Korea and is differentiated from the current one, has been developed. It is considered that the technology reduces work time and saves cost due to simplified joint connection of steel structure, unlike the current one. Moreover, since it is installed without a welding process in the field, industrial accidents would be reduced, which is likely to have economic competitiveness and satisfy.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.85-92
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• 2008

Strength of logs and round posts is compared and analyzed to estimate the strength of the incised Larix round posts treated with CCA in this paper. There is no significant difference in MOR of logs and round posts. However, in the incised Larix round posts treated with CCA MOE is decreased to about 9%, and there is 29% reduction in MOR as strength ratio is 0.71. When calculating the allowable bending stress of incised round type round posts, not in nominal 2-in timbers, an adjustment factor for MOE and bending strength is proposed as 0.91 and 0.71, respectively. Logs, round posts and the incised Larix round posts treated with CCA do not show significant difference in nail withdrawal load. There is almost no difference between incised Larix round posts treated with CCA and round posts in the shear strength of bolted joint. When calculating the allowable shear stress of bolted joint, it is conformed that considering the application of incising factor is not necessary.

• Journal of Korean Association for Spatial Structures
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• v.8 no.4
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• pp.65-71
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• 2008

The object of this paper is to evaluate on constructability of modular steel frame with the hollow structural steel section to LEB C-shape. A modular building is built with factory-manufacture and site-construction. The advantage of a Modular building presents that enhanced building quality, shortened construction period and easy at an expansion and enlargement for buildings but also has demerits such as size restriction of the modular units according to the Road Traffic Law and Inflexibility of the unit composition. So in this study we use light-weighted structure members with bolted joint for easy Knock-down and traffic, also we evaluated the constructability of this bolted joints type modular buildings.

• Journal of Korean Society of Steel Construction
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• v.20 no.5
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• pp.633-644
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• 2008

The structural framework design uses high-strength bolts and welding in column splices. However, for the column under high compression, the number of the required high-strength bolts can be excessive and the increase of welding results in difficulty of quality inspection, the transformation of the structural steels, and the increase of erection time. According to the AISC criteria, when columns have bearing plates, or they are finished to bear at splices, there shall be sufficient connections to hold all parts securely in place. The Korean standard sets the maximum 25% of the load as criteria. Using direct contact makes it possible to transfer all compressive force through it. The objective of this study is to examine the generally applied stress path mechanism of welded or bolted columns and to verify the bending moment and compression transfer mechanism of the column splice according to metal touch precision. For this study,22 specimens of various geometric shapes were constructed according to the change in the variables for each column splice type, which includes the splice method, gap width, gap axis, presence or absence of splice material, and connector type. The results show that the application of each splice can be improved through the examination of the stress path mechanism upon metal contact. Moreover, the revision of the relative local code on direct contact needs to be reviewed properly for the economics and efficiency of the splices.

• Journal of the Korean GEO-environmental Society
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• v.4 no.1
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• pp.67-75
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• 2003

In this study, the steel strip reinforcement bolted with braced angles expected to mobilize skin friction resistance as well as bearing resistance is proposed. Laboratory pullout tests are conducted to investigate the characteristics of pullout behavior. From the test results, friction effects between soil and reinforcement are evaluated with the width of reinforcement, magnitude of surcharge, and existence of bearing resistance member. Further to analyze interference effects for bearing resistance member, pullout tests are also carried by varing the number, the location, and the spacing of braced angles. Based on the test results, pullout resistance factor is evaluated under the consideration of location of braced angles and the degree of interference for spacing ratio.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.153-153
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• 2011

현대 건축은 기능적이고 합리적이었지만 획일적이었던 박스형 건축에서 탈피해 형태와 공간에 있어서 다양한 변화를 시도하고 있다. 특별한 건축물의 실현을 위해 각 나라의 기술력은 급속한 발전을 이루었고, 보다 더 독특한 건축물에 대한 관심은 비정형 건축물에 대한 관심의 증대로 이어지고 있다. 이러한 비정형 건축물에 적합한 구조로써 프리폼(Free-Form) 구조가 있다. 프리폼 구조로 입체골조(Double Layered Structure)를 많이 사용하였으나, 최근 유리로 되어 투명하고 기하학적 모양의 건축물을 추구함에 따라 평면골조(Single Layered Structure)가 증가하고 있는 추세이다. 평면골조는 축력 지배형과 모멘트 지배형으로 분류할 수 있고 프리폼 구조의 구성 요소 중 가장 취약하고 중요한 부분은 노드이다. 본 연구에서는 프리폼 구조 중 가장 큰 관심이 고조되고 있는 평면골조 모멘트 지배형의 노드에 대한 국내외 기술 분석을 통해 향후 연구 방향성을 제시하고자 한다. 입체골조는 하나의 노드에 여러개의 부재가 3차원으로 결합되어야 하기 때문에 다른 골조 시스템에 비해 노드부가 복잡하지만, 건축물의 외관을 유리로 하여 투명하게 하고 비틀리고 구부러진 구조물에 대한 건축적 요구가 많아짐에 따라 평면골조의 인기가 높아지고 있다. 이러한 시대의 흐름에 발맞추어 건물의 구조적, 기하학적 요구를 충족시키기 위해 다양한 노드 시스템이 개발 중이며, 가해지는 하중의 특성에 따라 축력 지배형과 모멘트 지배형으로 구분하여 노드의 양상을 분류할 수 있다. 축력 지배형의 대표적인 시스템은 다이아그리드(Diagrid)이다. 축력 지배형 프리폼 구조의 노드는 전체 구조물의 하중을 축력으로 받아 모두 전달해야 하기 때문에 크기가 크고 가새가 2~4개층에 걸쳐서 설치되기 때문에 중량이다. 모멘트 지배형 노드를 갖는 프리폼 구조의 형태는 대부분 지붕 구조로써 지붕 자체의 하중만을 견디도록 설계된다. 따라서 노드부와 노드에 붙는 부재들이 가볍기 때문에 사람이 들 수 있고 노드의 크기가 작아 시공성이 좋으며 대량 생산이 가능하다는 장점이 있다. 노드의 형태는 힘의 흐름과 쓰임에 따라 다양하다. 평면골조 모멘트 지배형의 노드는 접합방식에 따라 Splice node connection과 End-Face node connection 두 가지로 분류할 수 있다. Splice node connection은 각 부재의 종축으로 노드와 구조부재 사이에 이음재를 두어 연결하고, 연결 형태에 따라 전단력을 전달할 수 있는 1~2개의 접촉면이 생긴다. 전단응력을 받는 볼트로 이음재를 이어 조립하거나 용접으로 접합할 수 있다. 대표 노드로, SBP-1, SBP-2와 POLO-1 등이 있다. End-Face node connection은 각 연결된 부재의 단부와 노드 사이의 연결면은 종축방향의 수직이고, 인장응력을 받는 볼트를 사용하거나 용접에 의해 접합할 수 있다. 대표 노드로 SBP-4, WABI-1, MERO-1(Cylinder), MERO-2(Block), MERO-4(Double Dish) 등이 있다. 본 기술 현황 분석을 통해 현재 개발된 노드를 분류하고 가장 관심이 높은 Single Layer 모멘트 지배형 노드를 비교, 분석하였다. 최근 건물의 경향을 반영한 프리폼 구조를 실현하기 위해서 필수적인 노드의 개발은 국외에서 활발히 연구되고 있지만 그 기술이 개방되어 있지 않다. 국내에서는 동대문 디자인 플라자에 새로운 노드를 적용하고 고려대학교에서 모멘트 지배형 노드를 개발하는 등 발전 가능성을 보이고 있지만 국외 사례들에 비하면 아직 초기 단계라 할 수 있다. 따라서 현장 용접을 지양하고 공장 제작하여 현장에서 조립하며, 프로젝트 별로 상이한 노드를 사용하는 것이 아닌 다양한 요구를 효과적으로 수용하는 구조 효율성을 향상시킨 노드 상세의 개발이 이루어져야 할 것이다.

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.525-534
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• 2006

Column-to-beam pinned connections can cause local moment to the web of a steel tube due to the distance of eccentricity between the row of bolts and the column flange, which possibility deteriorates the load capacity of column. In this study, a square hollow section tubular used finite element analysis of a square hollow section tubular column was carried out, and the column width and thickness, existence and non-existence of internal reinforcement, and existence and non-existence of compressive force were taken as variables to examine the load capacity deterioration of a square column caused by moment. To guarantee the reliability of the finite element results, some specimens were fabricated and tested. The yield line method was applied to suggest the strength formulas of the square tubular column to the beam pinned connections. Based on the study results, the column strength the moment of the square hollow section tubular column to the beam pined connections improved with the increase in the w to strength limitations, a no-reinforcement type of square hollow section tubular column was proposed, and if the limitation values were not satisfied, the reinforcement of the internal column was made mandatory. Therefore, the horizontal -reinforcement type considered the strength increase, and the fabrication of the square hollow section tubular column was ar column that considered its load capacity with the moment for the no-reinforcement and the horizontal-reinforcement types.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.13-16
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• 2004

The PCS system, which consists of precast concrete column and steel beam, has been developed. The system is expected to achieve the effectiveness in the constructability and improve the structural performance under earthquake. New types of joint system for the panel zon and column connection has been developed in order to improve the shear strength capacity and rigidity of the of the system. The cyclic seismic test recommended by ACI was conducted to verify the structural performance of the system. As a test results, it is observed that the system satisfy most of the requirements by ACI criteria.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.1
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• pp.221-229
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• 2004

In Recent experimental research results of connection method between steel pipe pile and concrete footing are provided based on various experimental observations. It gives a shedding light toward developing better connection method for steel pipe pile at the field application. In this study, the newly developed method is tested for compressive, pull put and combination load including moment with carefully designed monitoring system. The measured data show that new method have at least equivalent or better load resistant capacities compared with those of specified method in Korea Road Design Specification. It is also tried to define and investigate the load transfer mechanism for new method.

• Journal of Korean Association for Spatial Structures
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• v.23 no.4
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• pp.97-105
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• 2023

The membrane structure should maintain the membrane materials in tension for structural stability guaranty. The anchoring part in the membrane structure is an important part. It has the function to introduce tension into membrane materials and function to transmit stress which membrane materials receives to boundary structure such as steel frames. In this paper, it grasps anchoring system of the anchoring part in the membrane structure concerning the fracturing characteristic condition of membrane structure, and the influence which is caused to yield it designates the stress state when breaking the membrane structure which includes the anchoring part and that stress transition mechanism is elucidated as purpose. This paper follows to previous paper, does 1 axial tensile test concerning the bolting part specimen, grasp of fracturing progress of the bolting part and the edge rope and hardness of the rubber, does the appraisal in addition with the difference of bolt tightening torque. As a result, the influence which the bolt anchoring exerts on the fracturing characteristics of the membrane material in the membrane structure anchoring part is examined.