• Title/Summary/Keyword: 합성부재

Search Result 254, Processing Time 0.029 seconds

Effect of Freezing and Thawing on Adhesion of Cement Concrete with Coarse-sand Coated FRP (규사코팅 FRP와 콘크리트 부착특성에 동결융해가 미치는 영향)

  • Lee, Gyu Phil;Park, Kwang Phil;Hwang, Jae Hong;Kim, Dong Gyou
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.17 no.2
    • /
    • pp.117-123
    • /
    • 2013
  • As fiber reinforced polymer (FRP) material is appled for a curved structure such as tunnel, FRP material must has a curved shape. Until now, the curved FRP material has been producted by hand-lay-up or filament winding work. It is impossible for mass production of the curved FRP material by these methods. Also, the quality of product by these methods is lower than that by pultrusion method. New pultrusion method and equipment had been developed for production of FRP material with steady curvature. The objective of this study is to evaluate the effect of freezing and thawing on adhesion of cement concrete with coarse-sand coated FRP in repair and reinforcement of cement-concrete structure using curved FRP material.

Analysis of a Behavior of Shear Stud in Steel-concrete Composite Beam using High-rise Building (초고층 건물에 적합한 합성보에서 전단스터드의 거동에 관한 비교 분석 연구)

  • Shim, Hak-Bo;Jang, Sung-Hoon;Park, Soon-Joen;Lee, Joo-Ho
    • 한국방재학회:학술대회논문집
    • /
    • 2010.02a
    • /
    • pp.34.2-34.2
    • /
    • 2010
  • 건물이 초고층화됨에 따라 고강도 콘크리트를 구조물에 적용하고 있으며 내화 시 폭열 예방을 위해서 고강도 콘크리트에 섬유를 첨가하는 경우도 있다. 초고층 구조물 합성부재에서 강재보와 콘크리트 슬래브의 합성작용을 위해서는 전단스터드를 필요로 하게 된다. 오늘날 제시된 전단스터드 설계식은 일반강도 콘크리트 실험에 의해 제시되었고 전단스터드는 항복강도에만 제한되는 것으로 나타났다. 따라서 본 논문은 초고층 건물에 적합한 고강도콘크리트를 기존 제안식으로 비교 분석하고 새로운 설계식의 필요성을 확인하며 ANSYS 모델링을 통한 전단스터드의 거동을 분석하는데 그 목적이 있다.

  • PDF

A Study on Load Bearing Capacity of Composite Member with Steel Rib and Shotcrete in NATM Tunnel (NATM 터널에서 강지보와 숏크리트 합성부재의 하중지지력에 관한 연구)

  • Moon, Sang Hwa;Shin, Young Wan;Kim, Seung Hwan;Yoo, Han Kyu
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.32 no.5C
    • /
    • pp.221-229
    • /
    • 2012
  • Steel ribs such as H-beam or lattice girder are often reinforced to secure the stability of NATM tunnel when the ground is in the bad condition. When designing, however, steel ribs are not often taken into consideration on the numerical analysis when they are regarded as temporary tunnel supports until shotcrete shows its best performance or if they are, there are various modeling methods. This study shows behavior and loading capacity of steel ribs and shotcrete through the strength test on the bending, pressure and full-scaled. Also, we conducted and analyzed the experiment of composite member consisting of shotcrete and steel ribs under the same condition. Through the result, we can find the fact that shotcrete and steel ribs do not work as one unit because of slipping on the boundary. Also, when numerical analyzing, it was concluded that steel ribs cover all bending moment and shotcrete and steel ribs share with axial force according to the compressive strength.

A Study on the Ductility of Concrete-Filled Composite Columns under Cyclic Loading (반복하중을 받는 콘크리트충전 강합성 기둥의 연성에 관한 연구)

  • 송준엽;권영봉;김성곤
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.5 no.6
    • /
    • pp.11-19
    • /
    • 2001
  • A series of test on concrete-filled composite columns was preformed to evaluate structural performance under axial compression and cyclic lateral loading. It was presented that concrete-filled composite columns had high strength, high stiffness and large energy-absorption capacity on account of mutual confinement between the steel plate and filled-in concrete. A cross section analysis procedure developed to predict the moment-curvature relation of composite columns was proven to be on accurate and effective method. The ductility factor and the response modification factor were evaluated for the seismic design of concrete-filled composite columns. It was shown that concrete-filled composite columns could be used as a very efficient earthquake-resistant structural member.

  • PDF

Automatic Algorithms of Rebar Quantity Take-Off of Green Frame by Composite Precast Concrete Members (합성 PC부재에 의한 그린 프레임의 철근물량 산출 자동화 알고리즘)

  • Lee, Sung-Ho;Kim, Seon-Hyung;Lee, Goon-Jae;Kim, Sun-Kuk;Joo, Jin-Kyu
    • Korean Journal of Construction Engineering and Management
    • /
    • v.13 no.1
    • /
    • pp.118-128
    • /
    • 2012
  • As the bearing wall structure, which has been widely applied to domestic apartment buildings since the 1980s, cause many problems during remodeling of buildings, the government encourages constructors to adopt flat plate or rahmen structure through legal incentives. In line with such a trend, the green frame, an eco-friendly rahmen structure that has removed the shortcomings of previous structures, was developed to enhance structural safety, constructability, and eco-friendliness. The construction of green frame can reduce the labor cost and facilitate the composition of iron bars to reduce rebar loss through calculating the quality and establishing the bar bending schedule automatically on the precast concrete member data collected over the design phase. Therefore, the purpose of this study is to develop the algorithm to automate the calculation of iron bar volume for the green frame designed on composite precast concrete members. Automated algorithm to calculate concrete structural design information and design information. Practices through the application site should prove efficacy. The database established by the developed algorithm will automate the establishment of iron bar processing map and bar cutting list and the calculation of optimal composition and order volume to minimize the rebar loss. This will also reduce the expenses on management staff and overall construction cost through the minimization of rebar loss.

Experimental Study on Flexural Capacity of Circular Concrete Beam Confined by Carbon Fiber Tubes (탄소섬유관으로 구속된 무근 원형 보의 휨성능에 관한 실험적 연구)

  • Lee, Kyoung-Hun;Hong, Won-Kee;Lee, Young-Hak;Kim, Hee-Cheul
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.11 no.1 s.53
    • /
    • pp.37-43
    • /
    • 2007
  • Experiments for circular unreinforced concrete beams confined by carbon fiber tubes (CFT) made of carbon fiber sheets were performed. Selected test parameter was thickness of carbon fiber tube: 1.5mm (3 layers), 2.0mm (4 layers), 2.5mm (5 layers), and 3.0mm (6 layers). Based on the test results, an equation for estimating moment capacity of the circular beams confined by carbon fiber tubes was proposed. Comparison results showed good agreement up to 2.5mm (5 sheets) of the CFT thickness.

Structural Behavior of Newly Developed Cold-Formed Steel Sections(II) - Flexural Behavior (신형상 냉간성형 단면의 구조적 거동(II) - 휨거동)

  • Song, In Seop;Kim, Gap Deuk;Kwon, Young Bong
    • Journal of Korean Society of Steel Construction
    • /
    • v.14 no.2
    • /
    • pp.357-364
    • /
    • 2002
  • The study performed a series of flexural tests on Closed Cold-Formed Steel Sections for stud, joist, and roof truss. Results were compared with analytical values. Each 2.4-m long and 0.9-m wide specimen consisted of two steel beams set at 0.46 m interval. The steel beams were attached to the specimens using either plaster board or ply wood. Another specimens did not use any attachment material. Positive and negative bending tests were conducted to investigate the composite behavior, including the effects of plaster board or ply wood on the buckling behavior of steel beam. Full-scale roof truss tests were also performed to study the buckling behavior and failure mode of the truss members.

Effect of the spandrel end beams on shear strength behavior in MTS systems (MTS (Multi-tee slab) 시스템의 테두리보가 전단 강도에 미치는 영향)

  • Kim, Min-Ki;Hong, Sung-Gul;Lee, Jong-Min;Cho, Yi-Hoon
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2008.11a
    • /
    • pp.189-192
    • /
    • 2008
  • Most existing double tee systems have need to improve flexure and shear design at their flanges in the section. In order to solve this problem we have devised MTS(Multi-tee slab) system, which is composed of several T-beams and applied spandrel end beams at each slab unit. The application of spandrel end beams has an beneficial effect on the shear strength and force distribution of slab unit because they support the ribs in the transverse direction. Numerical analysis shows that the spandrel end beams increase the shear strength. This paper represents the analysis of shear strength in MTS system and the effect of the spandrel end beams on the system.

  • PDF

A numerical study on feasibility of the circled fiber reinforced polymer (FRP) panel for a tunnel lining structure (터널 라이닝 구조체로서 곡면 섬유강화 복합재료의 적용성 검토를 위한 수치해석적 연구)

  • Lee, Gyu-Phil;Shin, Hyu-Soung
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.12 no.6
    • /
    • pp.451-461
    • /
    • 2010
  • Utilization of the fiber reinforced polymer (FRP) material has been enlarged as a substitution material to the general construction materials having certain long-term problems such as corrosion, etc. However, it could be difficult to apply the FRP material, which has a linear shape generally, to an arch-shaped tunnel structure. Therefore, an attempt has been made in this study to develop a device to form a designed cross section of FRP material by pulling out with a curvature. A sample of the circled FRP product was successfully produced and then the sample has been tested to identify its physical characteristics. Then, intensive feasibility studies on the circled FRP panel to be used for a tunnel lining structure have been carried out by numerical analyses. As a result, it appears that the new circled FRP-concrete composite panel has a high capability to be used for a tunnel lining material without any structural problem.

Flexural and Tensile Performance of Strain-Hardening Cement Composite with Synthetic Fibers (합성섬유를 사용한 변형경화형 시멘트 복합체의 휨 및 인장성능)

  • Kim, Sun-Woo;Lee, Min-Jung;Jang, Yong-Heon;Jang, Gwang-Soo;Song, Seon-Hwa;Yun, Hyun-Do
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2008.04a
    • /
    • pp.925-928
    • /
    • 2008
  • Fiber is an important ingredient in strain-hardening cementitious composite (SHCC), which can control fracture of cementitious composite by bridging action. The properties of reinforcing fiber, as tensile strength, aspect ratio and elastic modulus, have great effect on the fracture behavior of SHCC. To apply SHCC to structural member, SHCC must have economical efficiency and workability as well as own excellent tensile performance. For these purposes, four-point bending and direct tensile tests on SHCC with only hybrid synthetic fibers, total fiber volume fraction, $V_f$, is 1.5%, are carried out. The research emphasis is on the mechanical properties of SHCC made in Polyvinyl alcohol (PVA) and Polyethylene (PE) fibers, and how this affects the composite property, and ultimately its strain-hardening performance. Also, effect of hybrid type and water-cement ratio on the behavior of SHCC was evaluated in this paper.

  • PDF