STEEL CONSTRUCTION ENGINEERING
Online ISSN : 1884-0329
Print ISSN : 1880-9928
ISSN-L : 1880-9928
Volume 15, Issue 59
Displaying 1-10 of 10 articles from this issue
  • Koji KIUCHI, Takashi TAMAKOSHI, Mani ISHIO
    2008 Volume 15 Issue 59 Pages 1-9
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    In recent years, the crack damage by fatigue was confirmed in steel bridges, as a result, the design did fatigue durability collation by evaluation of a stress change to occur in a collation part was prescribed. However, in the arched bridges, relations of true stress and design stress are not always clear. Therefore difference in analysis model influences calculation stress greatly. Especially, the panel point parts shows a complicated stress property, therefore an analysis model has to be able to evaluate it adequately. This report is proposal of modeling and analytical technique in a fatigue design by examination of appropriate modeling and analytical technique.
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  • Kuniaki UDAGAWA, Shigenori TOGOU, Satoshi HIRATA
    2008 Volume 15 Issue 59 Pages 11-22
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    Tension braces are widely employed to enhance earthquake resistance in steel structures. These tension braces are connected to gusset plates welded to a beam-to-column connection by using high-strength bolts. The gusset plates at joints with high-strength bolts show three modes of failures: net section fracture, bearing fracture and end tearing fracture. In the conventional design method, the ultimate strengths for the net section fractures are evaluated based on an effective area at the last bolt. In this calculation, the width of the effective area is defined as a length for a spread angle of 60°C from the first bolt. However, the spread angle of 60°C is not always accurate depending on the number and edge distances of bolts. In the present research, we examine experimentally the effects of the number and edge distances of bolts on the ultimate strength of the tension gusset plates. We propose the effective widths and the spread angles to predict the ultimate strength of gusset plates for the net section fracture.
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  • Satoshi UCHIDA, Masahide MATSUMURA, Toshiyuki KITADA
    2008 Volume 15 Issue 59 Pages 23-32
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    Steel column members with Embedded Plastic Segment (EPS) has been developed and proposed as a new seismic retrofitting technique for existing steel bridge piers to enhance the ductility with less increment in the ultimate strength of the column members. In this paper, an application of the EPS method together with the ordinary concrete-filled method to an existing deck type arch bridge is investigate through static and dynamic analysis of the arch bridge. It is concluded from this analytical investigation that the validity of the application of the seismic retrofitting method using BPS method together with the ordinary concrete-filled method into the side ones of the deck supporting ridge framed column members and arch ribs of the deck type arch bride can be recognized.
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  • Masahiko YOSHIDA, Takehiko HIMENO, Masahide MATSUMURA, Toshiyuki KITAD ...
    2008 Volume 15 Issue 59 Pages 33-44
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    Damping devices, which are properly designed and installed, are effective in reducing the working stress, force, and displacement etc. of bridge structures during an earthquake. In application of damping devices, it is necessary to realize the basic characteristics of each device in terms of velocity dependence before selecting a device, adequate modeling for dynamic response analysis and so on. Then presented in this paper are the characteristics of the cylinder-type damper, which is one of damping devices for bridge structures, and an application example to an existing arch bridge.
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  • Masahiko YOSHIDA, Masahide MATSUMURA, Minoru SAKAIDA, Toshiyuki KITADA ...
    2008 Volume 15 Issue 59 Pages 45-56
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    Steel side blocks are set near the both sides of the rubber isolating bearings of a viaduct and are designed as a j oint protector to restrain the transverse displacement of the bridge against the Level 1 earthquake. The steel side block knocked off as a fuse member by the seismic load larger than the specified one can provide isolation effect not only in the direction of the bridge axis but also in the transverse direction against the Level 2 earthquake. Then this type of steel side block has been proposed by the authors on the basis of static loading tests. Proposed in this paper is a revised design method of this type of steel side block considering a contact speed between the side block and the bridge superstructure through dynamic loading test.
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  • Masaki YAMADA, Kuniyuki HIRAMOTO, Kai OIDE, Kenjiro TERADA
    2008 Volume 15 Issue 59 Pages 57-64
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    A numerical simulation system of ultrasonic tests is developed for characterizing the wave motions in steel structures with complicated shape. Geometry of 3D domain is generated by CAD software and converted into 3D volume picture elements (voxels), each of which is recognized as a finite element in the so-called voxel finite element method (FEM). An explicit scheme is employed in the dynamic voxel-FEM and is incorporated with parallel processing with MPI for large scale computations. After verifying the validity of the developed method, representative numerical examples are presented to demonstrate the capability of the system in visualizing the wave propagation phenomena to presumably detect the defects in joints embedded in steel structures.
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  • Kazutaka KINOSHITA, Hideharu NAKAMURA, Tomomi ISHIKAWA, Katashi FUJII
    2008 Volume 15 Issue 59 Pages 65-74
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    Although cracks have been caused at the welded portion in a steel chimney of thermal power plants constructed in islands, their causes are not necessarily clarified yet, and it is important for structural maintenance to investigate and to clarify the dominant factor of the cracks. In this study, we investigate the possibility of fatigue damage by local wind loads affected by geography. Fatigue damages are estimated based on the results of frequency response FEM analyses and local wind velocity by sixteen directions obtained by air flow simulations and wind data from nearby meteorological observatory. From the results of this study, relations between the fatigue damage due to local wind and cracks are quantitatively clarified.
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  • Susumu INOKUCHI, Daisuke UCHIDA, Atsunori KAWABATA, Takashi TAMAKOSHI
    2008 Volume 15 Issue 59 Pages 75-86
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    The purpose of this research is to investigate influence of asphalt pavement failure on local stress of orthotropic steel decks. Recently, fatigue cracks around the welds between deck plate and U-shaped rib have been reported in Japan. Then field surveys of fifty orthotropic steel decks were carried out to grasp their fatigue damages, asphalt pavement failures and so on. One of the major types of pavement failures was the crack that occurred just over the weld between deck plate and U-shaped rib. Then we conducted the field measurements at the orthotropic steel decks which had such pavement failures. It became clear that some pavement failures might make higher stress around the weld between U-shaped rib and deck plate. FEM analyses were also carried out to clarify the influence of types of asphalt pavement failures on local stress of orthotropic steel decks.
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  • Shintaro MATSUO, Tsuyoshi TANAKA, Kazuo INOUE
    2008 Volume 15 Issue 59 Pages 87-98
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    This paper proposes RHS-column to beam connections with an exterior diaphragm composed of two steel plates (hereafter called divided exterior diaphragm). The divided exterior diaphragm is expected to be constructed easier than the conventional connection. First, strength formulae of exterior diaphragms connected to beam flanges with high strength bolts are proposed, and loading tests showed that the calculated values of strength agreed well with the experimental values. Secondary, loading tests were performed in order to examine the elasto-plastic behavior of the divided exterior diaphragm connection. Major findings from the tests are summarized as follows. (1) The elasto-plastic behavior of the divided exterior diaphragm connection is the same as that of the conventional connection. (2) The web plate welded to the divided exterior diaphragm is effective against reduction of slip load and deformation of diaphragm slits.
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  • Takashi YAMA.GUCHI, Hiroshi MASUDA, Yuji KIMURA
    2008 Volume 15 Issue 59 Pages 99-107
    Published: September 25, 2008
    Released on J-STAGE: June 28, 2010
    JOURNAL FREE ACCESS
    Ultra high strength bolt, which strength is more than about 1000MFa has been developed by NIMS. For steel connections of civil/building structures, such bolts will make it possible to reduce the fabrication/construction cost and to change such joints simple and rational. In this study, pilot experiments using Ultra high strength bolts has been carried out to discuss feasibility of application of such bolts and to find further research problems for general use. 3 experiments have been executed; tensile tests for bolts considering actual situation of use, nut rotation angle tests and friction tensile tests for joints.
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