• Journal of Korean Society of Steel Construction
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• v.24 no.6
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• pp.637-645
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• 2012

The composite action in truss beam is generally achieved by providing shear connectors between the steel top chord of the truss and the concrete slab. The composite sections have greater stiffness than the sum of the individual stinesses of the slab and truss. Therefore, steel trusses that act compositely with concrete slabs can carry larger load and are stiffer and less prone to transient vibration. The crack pattern and deflection of the beam of the composte truss were investigated by using of 600MPa class steel in this study. The test results were compared with the results for the noncomposite trusses. Test results were also compared with the results of composite trusses by using of 400MPa class steel. It was ascertained that the case of high strength steel is more efficient compared with the case of SS400 steel for T-shaped steel.

• Journal of Korean Society of Steel Construction
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• v.23 no.1
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• pp.125-135
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• 2011

To obtain a lower story height with a long span and better fire resistance, a new composite floor system using GFRP (glass-fiber-reinforced plastics) was proposed. This floor system consists of asymmetric steel with a web opening, a hollow core ball, concrete, and GFRP. To evaluate the flexural performance of the new composite floor system, an experiment was conducted. The test parameters were the presence of GFRP, the void ratio in relation to the hollow core balls, and the web opening. The test results showed that the resistance and stiffness of the specimen with GFRP were 10% higher than those of the reference specimen, and that fully composite action was accomplished up to the yielding point. After the attainment of the yield strength, the ductility of the specimen was reduced due to the stress concentration around the web openings. The slip between the concrete and steel beam, however, was small. Thus, in the design of the proposed new floor systems, it is desirable that the calculated resistance be reduced by 15%, for safety.

• Journal of Korean Society of Steel Construction
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• v.22 no.2
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• pp.121-128
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• 2010

The current trends in steel construction involve the use of tapered sections to minimize the use of excess materials to the extent possible, by choosing cross-sections that are as economical as possible abandoning the classical approach of using prismatic members. In addition, snug-tightened connections, especially the end-plate type, have the advantage of fetching less construction costs and shorter assembly times as opposed to fully tightened joints. Although they have many merits, however, snug-tightened bolted end plates are extremely complex in their structural behavior. In this study, an experimental investigation of the snug-tightened flush end-plate connections of tapered beams were conducted. The primary test parameters were the torque for the clamping bolt, the loading pattern, the bolt type and the connection failure type. Using initial stiffness and load-carrying capacity as proposed by Silva et al. and AISC (2003), the moment-rotation curve of a linearly tapered member with a snug-tightened flush end-plate connection was predicted. Moreover, numerical and experimental data for moment-rotation curves were compared.

• Korean Journal of Construction Engineering and Management
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• v.18 no.5
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• pp.3-10
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• 2017

The HBS slab is a method in which a lightweight sieve is installed on top of the psc slab and two ribs of the neighboring psc slab are combined with ribs formed by the site concrete to act as a single member on the same axis. The purpose of this study is to implement the performance comparison with the existing method through the experimental study on the PSC slab method. In this study, the HBS slab was developed as a method to improve the limit of the existing method and the performance comparison with the existing method is tried to verify its superiority. The comparison of the structural performance with the existing method is carried out through the experimental study of the HBS slab, and the structural performance against the bending performance and shear and the bonding performance between the pc beam and the hbs slab are examined and compared with the existing method through the theoretical method.

• Journal of the Korea Concrete Institute
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• v.17 no.5 s.89
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• pp.687-694
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• 2005

In current design practice, the thickness of the floor slab has been determined to satisfy requirement for deflection control. However, previous study shows that the floor thicknesses in residential buildings may not satisfy the floor vibration criteria, even though the thickness is determined by the serviceability requirements in current design provisons. Thus it is necessary to develop the procedure to determine slab thickness that satisfies the floor vibration criteria. This study attempts to propose slab thickness for flat plate slab systems that satisfies floor vibration criteria against occupant induced floor vibration(heel drop load). Two boundary conditions(simple and fixed support), three square flat plates(4, 6, 8m), and five concrete strength($18\~30$ MPa) are considered. Since there are large uncertainties in loading and material properties, probabilistic approach is adopted using Monte-Carlo simulation procedures.

• Journal of Korean Association for Spatial Structures
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• v.7 no.3 s.25
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• pp.119-124
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• 2007

Due to the deficit of section of web, the buckling strength of cellular beam become smaller than that of H-beam. In this thesis, we evaluate the buckling strength of web-post through non-linear F.E.M with opening distance-diameter ratio and opening diameter - web thickness ratio as essential variables. And also analyzes this comparing with the standard indicated in BS5950 Part 1.

• 건축구조
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• v.17 no.3
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• pp.41-47
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• 2010

현대산업사회에서는 혁신적인 디자인, 초대형, 장스팬 등 구조엔지니어링이 필요한 다양한 건축물들이 시공되고 있으며, 포스트텐션 공법은 이러한 기술적 요구를 수용하는데 있어 좋은 해결방법의 하나로 적용이 늘어나고 있는 공법이다. 이에 본지에서는 지난호(3월)의 "포스트텐션 공법의 소개"에 이어 경제성을 비교분석하여 포스트텐션 공법적용의 장점을 소개하고자 한다. 경제성 비교에서는 공법에 사용되는 인건비와 재료비 등의 직접비용을 제외한 공기, 유지관리, 해제 등 다양한 요소들이 고려되며, 각 건물의 특성에 따라 달라지므로 명확한 경제성 분석을 하기는 힘들다. 그러므로 본 기사에서는 포스트텐션 공법의 경제성에 영향을 주는 요소들을 분석하고, 각 구조 공법의 상대비용을 비교하여 포스트텐션 공법 적용을 위한 가이드라인을 제공하고자 한다.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.619-624
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• 2002

A prestressed/precast concrete system was used to build the new Asian Olympic Stadium Project in Pusan, Korea. The stadium(mainly intended for cycle racing) is designed for the 2002 Asian Olympic Games and has a seating capacity of 20,000 spectators plus a few private suites. More than 1300 prestressed/precast components were used and they include single columns, primary beams, cantilever beams, double riser stands, and double tees. Especially, a total of 24 cantilever beams is used on the fourth story for the stands and double tees. These 8m long beams are post-tensioned to prevent cracking, to increase their durability and to serve serviceability by vibration. A cantilever section with cast-in-place topping is 800mm wide and 1500mm deep. Cantilever beams are connected to the column with the corbel by cast-in place concrete. Bonded post-tensioning tendons were assembled at the job site. Dead-end anchorages were installed in the end of cantilever beams and live-end anchorage is the opposite of them. This article presents the geometric layouts, design features and so on.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.53-56
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• 2007

It was previously introduced a new displacement measuring technique using terrestrial laser scanning (TLS) that remotely samples the surface of an object using laser pulses and generates the three-dimensional (3D) coordinates of numerous points on the surface. In this paper, for an assessment of the capabilities of the measuring technique about existing structures, the field tests for vertical displacement measurement of an existing long span steel box-girder are experimentally carried out. The performance of the technique is evaluated by comparing the displacements obtained from TLS system and displacements directly measured from linear variable displacement transducer (LVDT).

• 건축구조
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• v.17 no.1
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• pp.78-83
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• 2010

포스트텐션(Post-Tension, PT) 공법은 일반적으로 텐던(tendon)으로 알려진 고강도 강선 또는 봉을 이용하여 콘크리트 또는 다른 재료를 보강하는 방법으로 많은 경우 건설현장의 제약과 건축적인 요구에 의해 다른 공법으로 해결이 불가능한 경우에 대해 대안으로 사용되어 온 공법이다. 또한 포스트텐션 시스템은 조립과 설치에 특수한 지식과 경험이 필요하였다. 그러나 최근 건설시장은 신소재와 신공법의 발달과 함께 친환경 및 경제성에 대한 요구가 증가함에 따라 장스팬 및 층고절감이 가능한 포스트텐션 공법을 일반 건축물에 적용하는 사례가 점차 늘어나는 추세에 있다. 따라서 본 지에서는 3회에 걸쳐 포스트텐션 공법과 설계 및 시공사례 등을 소개하고자 한다. 1. 포스트텐션 공법 소개 2. 포스트텐션 공법의 경제성 비교 3. 포스트텐션공법의 설계사례와 설계시 고려사항