• Title/Summary/Keyword: 강재보

Search Result 581, Processing Time 0.025 seconds

Evaluation of Relative Corrosion Rate depending on Local Location and Installation of Structural Member in Steel Water Gate (강재 수문의 부재 위치 및 설치 방향에 따른 상대 부식속도 평가)

  • Ha, Min-Gyun;Jeong, Young Soo;Park, Seung hun;Ahn, Jin-Hee
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.23 no.7
    • /
    • pp.16-24
    • /
    • 2019
  • The corrosion amounts of steel structures can be different depending on their installation condition and height. Thus, their corrosion maintenance should be considered depending on installation conditions of local structural members. In this study, an atmospheric exposure test was conducted to evaluate the corrosion amount and the corrosion rate depending on the installation condition and height of a steel water gate using monitoring steel plates and corrosion environment measuring sensors. The mean corrosion depth was evaluated using the weight loss method and the galvanic corrosion current was measured by corrosion environment measuring sensors. Local corrosion rate of local structural member in steel water gate was estimated using measured mean corrosion depths and galvanic corrosion currents. From this measurement results, the corrosion damage in horizontal member of the cross beam was highly evaluated than those of other structural member as skin plate, etc. The relative difference in the corrosion rate of a local structural member could be highly affected by local corrosion environments of steel water gate members. Therefore, an appropriate maintenance method should be considered for local corrosion damages of local structural members determined by local corrosion environments of a steel water gate.

Ductile Behavior of Ultra High Performance Fiber Reinforced Concrete Segmental Box Girder (초고강도 섬유보강 콘크리트 분절형 박스거더의 연성 거동)

  • Jeong, Min-Seon;Park, Sung-Yong;Han, Sang-Mook
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.5 no.3
    • /
    • pp.282-289
    • /
    • 2017
  • The flexural behavior tests of UHPC segmental Box girder which has 160MPa compressive strength and 15.4m length were carried out. The test variables are area of prestressing wires, volume fraction of steel fibers and longitudinal reinforcing bars in upper flange and web. PS tendons which has 32 strands of 15.2mm diameter in lower flange, 24 strands and 14 strands in lower flange were arranged and volume fraction of 2%, 1.5% and 1.0% is used in box girder concrete. UHPFRC box girder which has 32 strands in lower flange showed the over reinforcement and brittle behavior. UHPFRC box girder which has 24 strands showed the similar peak load as 32 strands girder and ductile behavior as large deflection. UHPFRC box girder which has 14 strands showed half of the peak load of 24 strands box girder and ductile behavior. After the application of the formular for the reinforcement index to the behavior of the UHPFRC box girders, reinforcement index does not determine the characteristic of behavior of UHPFRC box girder exactly. So the index should consider the dimension precisely and modify the reference value corresponding to the 0.005 strain of the prestressing strands.

A Proposal for an Evaluation of Flexural Resistance of Longitudinally Stiffened Plate Girder with Slender Web (수평보강재로 보강된 세장 복부판을 갖는 플레이트 거더의 휨강도 평가 방법의 제안)

  • Park, Yong Myung;Lee, Kun Joon;Choi, Byung Ho;Back, Sung Yong
    • Journal of Korean Society of Steel Construction
    • /
    • v.26 no.2
    • /
    • pp.119-132
    • /
    • 2014
  • In this paper, a series of numerical analyses were performed to evaluate the flexural resistance of steel plate girder with longitudinally stiffened and slender web. The SM490 steel was adopted for the study and the flexural resistances evaluated from the numerical analysis were compared with those suggested by the AASHTO LRFD and the Eurocode 3 codes, respectively. It was found that the AASHTO LRFD code could considerably underestimate the flexural resistance as the web slenderness becomes smaller. This comes from the fact that current AASHTO LRFD code does not consider a possible increase of slenderness limits for compact and noncompct web, and also an additional effect of web restraint on the rotation of compression flange in longitudinally stiffened web. Therefore, the slenderness limits of web and flange have been newly proposed for the plate girders with longitudinally stiffened web and it is analytically verified that the flexural resistance can be appropriately estimated by applying the proposed slenderness limits to the AASHTO LRFD code.

Design Improvements for Crossbeams and Stringers of Steel Box Girder Bridge (강박스거더교 가로보와 세로보 합리화 연구)

  • Gil, Heungbae;Kang, Sang Gyu;Cho, Jun Sang
    • Journal of Korean Society of Steel Construction
    • /
    • v.20 no.1
    • /
    • pp.1-8
    • /
    • 2008
  • This research carried out to optimize crossbeams and stringers of steel box girder bridges, which are parts of floor system and support loading from the bridge deck. In the current design practice, the crossbeam is densely deployed with a spacing of 6 meters, and the stringer is placed between the crossbeams. The crossbeams and stringer are connected to the deck through slab anchors but the allowable stress of the compression flange is determined by the lateral-torsional buckling. To increase economic efficiency of the steel box girder bridges. the increased spacing of the crossbeam was studied. The study shows that the spacing can be increased up to 10 meters. However, higher strength steel plates are necessary. Shear studs rather than slab anchors are also recommended to prevent lateral-torsional buckling strength of the crossbeams and stringer.

Evaluation of fire resistance according to load ratio and limit temperature (하중비와 한계온도에 의한 강구조 부재의 내화성능평가법 제안)

  • Kwon, In-Kyu;Kim, Heung-Youl
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2010.04a
    • /
    • pp.395-399
    • /
    • 2010
  • 강구조 부재의 내화성능평가를 위한 비재하가열시험은 강재 허용온도로 평가되고 있으나, 강재의 허용온도 설정은 H형강 부재의 최대하중로 평가되는 한계용도와 고온에서의 강소재의 허용응력도 능력으로 설정되었으므로 실지 작용되는 강구조 부재의 하중조건과 다양한 부재의 종류 등의 관점에서 허용온도의 적용은 다소 불합리한 점이 있다고 판단된다. 따라서 본 연구에서는 강구조 건축물에서의 부재에 작용하는 하중에 따른 내화성능의 차이를 보이고 이에 따른 합리적인 내화성능 평가방법을 제안하고자 한다.

  • PDF

The Structural Behavior of Semi-Rigid Connections with Reformed T-stub by Using of SS400 Steel (SS400 강재를 사용한 개량 T-stub 반강접합부의 역학적 거동)

  • Lee, Myung Jae;Yang, Myung Sook;Cho, Won Hyuk
    • Journal of Korean Society of Steel Construction
    • /
    • v.11 no.2 s.39
    • /
    • pp.241-241
    • /
    • 1999
  • The analysis and design of steel frames are usually carried out under the assumption that the connections of beam-to-column are either fully rigid or ideally pinned. However the connections actually show semi-rigid behavior in many cases. The authors investigated the structural behavior of simi-rigid connection with reformed T-stub by using of SM490 steel. The objective of the study is to investigate the structural behavior of the beam-to-column semi-rigid connection with reformed T-stub, which is made of SS400 steel. The beam-to-column connections by using reformed T-stubs were tested under monotonic loading and cyclic loading condition. The possibility of application of semi-rigid connections with reformed T-stubs was ascertained from test results.

  • PDF