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Volume 7 (1997)
- Issue 4 Pages 210-
- Issue 3 Pages 140-
- Issue 2 Pages 72-
- Issue 1 Pages 4-
Volume 7, Issue 1
Displaying 1-6 of 6 articles from this issue
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Hiroshi TERATA1997 Volume 7 Issue 1 Pages 4-19
Published: March 15, 1997
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSInformation is given to show various analytical methods which are based upon simple torsion theory, bending-torsion theory (theory including bending-torsion) or simplified ideas to facilitate quick calculation. The relationships and differences between each method are clarified to help choose the proper method for analytical cases and purposes. The effect of bending-torsion appears more strongly in the stress distribution of the gate section rather than the internal forces of the section and can be calculated by the finite element method more accurately. Sound designs would not be obtained for super large gates of torsion type without considering gate deformation due to bending-torsion as well as simple torsion. Although torsion type structures have several advantages essentially of a structural nature, its application is not familiar and not used often in actual structures. The difficulty of structural analysis is one of the reasons.View full abstractDownload PDF (3697K) -
Kimifumi YAKUSHIJI, Josuke KASHIWAI1997 Volume 7 Issue 1 Pages 20-26
Published: March 15, 1997
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSOn maintenance for gates set up dams during the long-term of dam working, maintenance is as significant as the initial construction cost in economical consideration. In recent years, materials hard to inferior and structures easy to inspect and repair have been adopted for simple and easy maintenance. To estimate development of these technologies properly, study in their economical aspects will be hoped. In this report on dam gates of spillways and outlets for flood control, actual state of maintenance cost will be grasped and estimated.View full abstractDownload PDF (1545K) -
Kazuo KONAGAI, Takashi MATSUSHIMA1997 Volume 7 Issue 1 Pages 27-31
Published: March 15, 1997
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSStability of a granular slope during earthquakes is usually evaluated assuming Coulomb's friction on its internal shear plane, and thus, acceleration of seismic motion is an important parameter for the evaluation of its stability. Irreversible deformation of a granular slope however is mainly due to a change in its fabric accompanied by noticeable dilation, through which a certain amount of energy is consumed. It is therefore noted that ground velocity as well as acceleration is another important key providing a stability index. On the basis of findings through experiments by means of a new visualization technique, Laser-Aided Tomography, a simple approach for the evaluation of dynamic slope stability is discussed.View full abstractDownload PDF (2103K) -
Tasuku YOSHIMURA, Jun TSUMORI, Tatsuo OTA, Takashi YAMAMOTO1997 Volume 7 Issue 1 Pages 32-39
Published: March 15, 1997
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSRecently, we have proposed the method-current control using dispersed aeration-that is able to restrain abnormal increase of algal bloom by controlling the current artificialy as one of the techniques for preserving water quality in reservoirs. We carried out field test on this current control system as measures against water quality control for reservoir at Terauchi Dam for a month, reported upon effect on water quality with facilities for circulatory fluid control in this paper. As a result, we confirmed the function on the current control system, effect onwater quality control in the reservoir and hydraulic stability of facilities for circulatory fluid control.View full abstractDownload PDF (1802K) -
Shuuji MIYATA, Katsuya TODO1997 Volume 7 Issue 1 Pages 40-48
Published: March 15, 1997
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSConcrete placing was carried out during freezing weather in winter at the Miura dam to repair its intake tower, which had produced visible degradation in concrete after 70 years of service. The facility, located in mountainous terrain in central Japan and used exclusively for electric power generation, performs its flow-regulating duty throughout the year and, thus, there were restrictions on the method and timing of repair work to minimize adverse impact on power generation. The work was executed in winter when freezing weather prevails but the level of water in the reservoir remains relatively low. Lithium nitrite was used as an admixture in concrete in a bid to compensate for lack of sufficient curing time and to prevent initial frost damage. It was confirmed that the quality of concrete can be assured by adding lithium nitrite without the need for providing any special curing process, such as thermal insulation or heating.View full abstractDownload PDF (2328K) -
Isamu HIRANO, Hideto NAMIKI, Michihiko NISHIBAYASHI, Kohkichi KIKUCHI, ...1997 Volume 7 Issue 1 Pages 49-54
Published: March 15, 1997
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe authors have carried out an in situ experiment in the foundation of Yamaguchi regulating reservoir (rock fill type dam), which is composed of cretaceous granite, in order to examine the grouting effects on deformability of rock masses. As the results, it is clarified that deformability of rock masses can be improved by grouting as well as permeability.View full abstractDownload PDF (1345K)
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