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Volume 10 (2000)
- Issue 4 Pages 276-
- Issue 3 Pages 169-
- Issue 2 Pages 82-
- Issue 1 Pages 5-
Volume 10, Issue 2
Displaying 1-7 of 7 articles from this issue
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Toshiyuki ADACHI2000 Volume 10 Issue 2 Pages 82-92
Published: June 15, 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (6800K) -
Xianjing KONG, Tong ZHU, Guocheng HAN2000 Volume 10 Issue 2 Pages 93-101
Published: June 15, 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSIn order to discuss effects of possible measures for enhancing the stability of a concrete-faced rock-fill dam (CFRD), a series of model experiments are conducted. The measures discussed herein include the followings: firstly, some sheets of geo-textile are sandwiched horizontally in the upper interior of a dam model, and secondly, a face slab on a model's upstream slope is extended to cover up the upper 1/3 part of its downstream slope. The extended part of the face slab is then fastened to the underlying granular slope with steel rods arranged side by side in squares. Comparing these measures with those tried out in the authors' previous experiments, a rational combination, which may contribute to saving a large amount of earthwork, is discussed.View full abstractDownload PDF (2626K) -
Hiroshi MORIMOTO, Tetsuya KOKUBO, Yasumune SHIGEMITSU2000 Volume 10 Issue 2 Pages 102-115
Published: June 15, 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSThe behavior of a concrete arch dam was examined through a model experiment. Mortar was employed as model material containing limestone minute, causing its strength to be greatly reduced. A seismic record from Hyogo-ken-Nanbu Earthquake was used as an input base motion with its time scale and amplitude adjusted so that the law of similarity would be satisfied. The observed motion was then compared with a numerical simulation in which development of cracks is taken into account. The agreement between the experimental result and the numerical simulation was satisfactory, suggesting that tensile cracks might have been induced at the bottom of the dam's upstream surface. The numerical method, which successfully described the observed motion of the dam model, is thus considered to allow the crack-associated behaviors of an actual concrete dam, as well as its stability during an intense earthquake, to be discussed.View full abstractDownload PDF (4129K) -
Takeyoshi SADAHIRO, Isamu HIRANO, Keiichirou SAKAMOTO, Junko KOIKE2000 Volume 10 Issue 2 Pages 116-127
Published: June 15, 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSIn order to estimate the residual porewater pressure of landslide due to rapid drawdown of reservoir level rationally, the behavior of groundwater is observed and analized for 16 landslides, their geology is crystalline shist, Mesozoic-Paleozoic sedimentary rock, and Ryoke granite. The observed data show that the groundwater residual ratio is below 20 percent at drawdown speed 0.5-0.8 meter per day, and the residual ratio depends on geological characteristics of slip block. To use the result, we can estimate the groundwater residual ratio rationally.View full abstractDownload PDF (3136K) -
Kunihiko AMANO, Yoshiya YASUDA, Hiroyuki SUZUKI2000 Volume 10 Issue 2 Pages 128-137
Published: June 15, 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSA handy method was developed to assess reservoir water quality before the completion of dam reservoirs using information such as river water quality which is available even before the completion of reservoirs. Regression equation for mean surface Chlorophyll-a concentration in summer was obtained by using water quality data which have been measured in existing reservoirs and flowing in rivers. Since this method provides quantitative water quality prediction, it can complement the water quality assessment made by numerical simulations. Also have analyzed were distributions of several water quality indices when common phytoplankton species are abundant. This analysis showed the preference of phytoplankton species and it can be used to predict dominant phytoplankton species in reservoirs qualitatively when combined with outcomes by numerical simulations.View full abstractDownload PDF (2489K) -
Tatsuo OHMACHI2000 Volume 10 Issue 2 Pages 138-150
Published: June 15, 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSSeveral dams were damaged by the 1999 Chichi, Taiwan earthquake (Mw7.5). Among them, the severest was collapse of Shih-Kang Dam. The dam is located at about 25km from the mouth of the Ta-Chia Creek, constructed for domestic uses in 1977. It is a 357m long concrete gravity dam, equipped with 18 spillway gates and 2 sediment flushing gates. Due to fault dislocation of the earthquake, the right half side of the dam and the intake tunnel on the left bank side were crushed to pieces with 7.5m and 3.5m differences in level, respectively. Suishih Dam and Toushi Dam are respectively 30.3m- and 19m-high earth dams with vertical concrete cores, located at the Sun-Moon Lake. They were caused several longitudinal cracks and settlement exceeding 10cm. At Liyutan Dam which is a 96m-high rockfill dam, a 10cm-wide opening was observed at the left end of the crest and a maximum settlement of the dam body was about 10cm.View full abstractDownload PDF (5312K) -
2000 Volume 10 Issue 2 Pages 151
Published: 2000
Released on J-STAGE: April 30, 2010
JOURNAL FREE ACCESSDownload PDF (138K)
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