著者

M. A. ELZEIR T. HIBINO

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.43, pp.827-832, 1999-02-10 (Released:2010-08-25)

参考文献数

12

被引用文献数

1 2

---

The Suez Canal is an important water-transport route all over the world. Two hydrodynamic issues related to the flow within the canal are worthy of consideration: sedimentation in the northern section of the canal and high velocity current in the southern section of the canal. To address the sedimentation issue, a large program of dredging works is being undertaken. A numerical model is presently being developed to simulate flow in the canal with a special attention paid to the south part. This model is the focus of the present study. The model is a two-dimensional depth averaged finite element model utilizing independent open boundaries at the north and south ends of the canal. The radiation and modified long wave boundary conditions are compared. Due to its accuracy and flexibility to suit different forcing conditions, the radiation boundary condition shows superiority over the modified long-wave formulation. The simulation results reflect most of the physical phenomena observed in the canal.

著者

宇多 高明 木暮 陽一 平野 一彦 大内 香織 三波 俊郎 熊田 貴之

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.51, pp.1325-1330, 2007 (Released:2010-08-25)

参考文献数

8

---

Numerical simulation using the contour line change model was carried out to restore the sandy beach on the lakeshore in Ukishima area in Lake Kasumigaura. Past aerial photographs were compared to investigate the long-term shoreline changes of the Wadamisaki sand spit formed in the southeast part of the lake. The predominant wave direction of wind waves was determined from the shoreline changes in Ukishima area. Given the wave height predicted using the SMB method and predominant wave direction, the optimum arrangement of groins was determined using the contour line change model considering the effect of grain size changes.

著者

品川 守 舘谷 清 山口 甲

出版者

公益社団法人 土木学会

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

no.36, pp.305-310, 1992

被引用文献数

2

---

Eighty years have passed since systematic improvement of the Ishikari River started in 1910. Before the improvements, the Ishikari River was in a completely natural state, and caused floods every year due to its meandering stream. The goal of the improvements was to further the development of Hokkaido by rcelaiming the vast marshes along the Ishikari River. The improvement work involved channel improvement of river, mainly by (1) excavating short-cuts to shorten the river and lower the flood stage, and (2) construction of continuous embankments to prevent floods.<BR>As a result, flood protection has improved remarkably and allowed the development of new residential areas. Flood prevention and reduction in water-levelsby the short-cuts have changed the Ishikari Marshes to fertile arable land.<BR>This study will clarify how channel improvements in the Ishikari River executed for regional development contributed to a change in flood flows and decreases in floods.

著者

品川 守 舘谷 清 山口 甲

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.36, pp.305-310, 1992-02-20 (Released:2010-06-04)

参考文献数

2

被引用文献数

3 2

---

Eighty years have passed since systematic improvement of the Ishikari River started in 1910. Before the improvements, the Ishikari River was in a completely natural state, and caused floods every year due to its meandering stream. The goal of the improvements was to further the development of Hokkaido by rcelaiming the vast marshes along the Ishikari River. The improvement work involved channel improvement of river, mainly by (1) excavating short-cuts to shorten the river and lower the flood stage, and (2) construction of continuous embankments to prevent floods.As a result, flood protection has improved remarkably and allowed the development of new residential areas. Flood prevention and reduction in water-levelsby the short-cuts have changed the Ishikari Marshes to fertile arable land.This study will clarify how channel improvements in the Ishikari River executed for regional development contributed to a change in flood flows and decreases in floods.

著者

辻本 浩史 後藤 祐輔 竹下 航 田中 創

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.50, pp.559-564, 2006 (Released:2010-08-25)

参考文献数

8

---

The large and severe typhoon No.14 passed through along the west Kyusyu on September 4th-7th, 2005. The speed of typhoon was low, so, the heavy rainfall continued for a long time. Total rainfall of many observation points exceeded the maximum record and the water level of Ooyodo River, Komaru River and Gokase River exceeded the high water. 15, 000 or more people in Miyazaki city and 50, 000 or more people in Nobeoka city were ordered to refuge. A lot of meteorological information was able to get by internet-web-sites . Among them, the accuracy of the forecast information of 24 hours rainfall and the efficiency of the spatial and temporal information of flood risks was verified. As the results, it was shown that these information which support self-help, co-help of inhabitants are useful for the disaster prevention.

著者

大本 照憲 藤見 俊夫 小場 隆太

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.52, pp.451-456, 2008 (Released:2010-08-25)

参考文献数

5

被引用文献数

8 3

---

There are two measures to reduce human damage resulting from a flood flow, that is, preventive public facilities as hardware-like aspect and residents' evacuation from inundation flow risk as software-like aspect. Since the former has a practical limit when the facilities are attacked by the flood flow beyond their strength, at that time the latter becomes important. From this viewpoint, we picked up six areas from the Sendai river basin affected by flood disaster at the latter half of July in 2006 and executed questionnaire survey to the residents about evacuation activities, needs of disaster information, understanding of flood hazard map and awareness to flood disaster. Moreover, we analyzed effects of disaster forces on evacuation activity. This paper showed that social cohesion played an important part in a community's ability to respond to flood disasters.

著者

和田 一範 村瀬 勝彦 冨澤 洋介

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.49, pp.493-498, 2005-02-01 (Released:2011-06-27)

参考文献数

7

被引用文献数

4 4

---

The influence of global warming on hazard risk is estimated from the results of the regional climate model by Japan Meteorological Agency and Meteorological Research Institute. The horizontal resolution of the model is about 20km and the model outputs are expected to be useful for the risk assessment of the future. Before beginning the risk assessment, the model output values during 1981-2000 were verified by comparing with observed precipitation data. The verification shows that the precision of the models are generally well in representation of the precipitation, the normal value of the monthly precipitation and the annual maximum daily precipitation in each region. According to the analysis from the model outputs, the extreme daily precipitation in 100-yr time period will increase in some parts of western Hokkaido, northern Tohoku region, Hokuriku region and Nansei islands during 2081-2100. While, the result of the seasonal variation of precipitation shows that the precipitation will decrease especially in many areas in Japan except Hokkaido region from winter to spring, and the drought risk will increase there.

著者

中村 要介 土屋 十圀

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.50, pp.361-366, 2006 (Released:2010-11-30)

参考文献数

17

---

This study estimated the safety degree of flood control at Yattajima, the Tone River, Japan to verify effects of additional dams. Rainfall events considered are Catherine Typhoon in 1947, Ise Bay Typhoon in 1959, the Typhoon No. 15 in 1981, and the Typhoon No. 5 in 1998. The storage function method was used for runoff analysis, which showed good agreement between observed and computed discharges. Using the spatiotemporal rainfall pattern of Catherine Typhoon, this study simulated rainfall-runoff at each time stage; 1959 with two dams, 1981 with five dams, and 1998 with six dams (the same as present situation), and evaluated the effect of these added dams on flood control in terms of the decrease of peak discharge at Yattajima. The decreases estimated were 513-1, 253 m3/s for the 1959 situation; 2, 025-2, 765 m3/s for 1981; and 2, 233-2, 973 m3/s for 1998. It is also verified that the present situation with six dams can cope with 200-year floods, which is significant improvement because the past situation without dams could cope with 100-year floods.

著者

早川 敬之 藤田 昌史 芳賀 弘和 坂本 康

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.49, pp.1531-1536, 2005-02-01 (Released:2011-06-27)

参考文献数

7

---

It is necessary to evaluate the characteristics of river environment for planning river works and for setting an environmental target of preservation and improvement of habitats. Therefore the technique to analyze the relation between the distribution of living things and physical, chemical and biological environments of river habitats is required. In this paper, we presented an integrated water quality index and an integrated river flow type index. The latter was based on results of principal component analysis applied to the factors involved in HIM (Morishita, 1998). The integrated indices were used as criterion variables for a multiple regression analysis of fish data and some indicator species were presented. The multiple regression model was used for the estimation of integrated index values of verification rivers and showed good performance.

著者

松永 信博 増田 壮佑 中牟田 大嗣 徳永 貴久 矢野 真一郎 押川 英夫 橋本 彰博 藤田 和夫 古賀 雅之 岩下 智明 原田 敦彦

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.52, pp.1291-1296, 2008 (Released:2010-08-25)

参考文献数

8

---

Laboratory experiments were carried out on water quality purification with EcoBio-Block (EBB). EBB is a porous concrete block including Bacillus subtilis natto group. In this study, we examined experimentally denitrification effect of EBB by letting it live together with denitrification bacteria in soil. The time variations of TN, ON, DIN, NH4-N, NO2-N, and NO3-N were obtained under the aerated condition by changing the weight ratio of EBB to water. On the basis of those data, the denitrification rate, the mineralization rate, and the decreasing rate of DIN were obtained. As a result, we confirmed that the processes of organic matter decomposition, nitrification, and denitification were performed effectively by the symbiosis of useful microbial group and denitrifying bacteria.

著者

塩月 宏治 木村 喜代治 長林 久夫

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.38, pp.301-306, 1994-02-28 (Released:2010-08-25)

参考文献数

2

---

This paper describes the relationship of the characteristics of water temperature and the conditions of water qualities in Lake Onogawa. The field observation was conducted from Augast, 1991 to October, 1992. As the results of these observations, the relationship of turbidity (TB) to 665nm absorption and potential of hydrogen (pH) to oxidation reduction potential (ORP) are discussed.

著者

米山 望 守屋 祥一

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.39, pp.373-378, 1995-02-28 (Released:2010-06-04)

参考文献数

7

被引用文献数

2

---

A computer code for analyzing 2-dimensional fluid flow with free surface has been developed. The main features of this computer code are (1) the modifica-tion of a VOF technique with improved numerical accuracy of stress boundary condition and the mass conservation law on free surface, and (2) the introduce of a k-ε model in which an attenuating behavior of turbulent intensity near free surface can be expressed.The results of verification show that the numerical solutions agree well with the experimental data for free surface shape and velocity profiles.

著者

平野 順子 馬籠 純 石平 博 竹内 邦良

出版者

公益社団法人 土木学会

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.49, pp.385-390, 2005

被引用文献数

1

---

A geo-referenced global dam reservoir database is constructed by assembling several published dam inventories and latitude/longitude coordinates that are digital obtained or decided from printed maps. This database is designed for hydrological applications on river basin scale to the global scale, and 15, 317 dams with 29 dam reservoir attributes are registered in it. A shoreline polygon data of the reservoir/lake is also provided for 4, 204 dams. The total storage capacity of the registered dams is 5, 594km<SUP>3</SUP>, which is equivalent to the 70% of total storage capacity of all reservoirs and lakes over the world (7, 000 km<SUP>3</SUP>). Since geo-referenced reservoir database which covers whole global area is rarely available, the database will greatly contribute for global scale water resources analysis and impact assessment of reservoirs on the freshwater systems.

著者

門田 章宏 鈴木 幸一

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.51, pp.721-726, 2007 (Released:2010-08-25)

参考文献数

17

---

Groynes have been used for the stabilization of banks and for creating a navigation channel by confining the cross-sectional area, especially for large European and Japanese rivers. Therefore, turbulent flows and transport phenomena in groyne fields have paid attention to the appropriate design for bank protection and obtainment of enough depth in the main channel as well as the proper environment for ecosystems. In the present study, mean and coherent flow structures around single groyne under emerged and submerged conditions were experimentally discussed. In order to investigate the flow pattern around the single groyne, a scaled and schematized model was implemented and experiments were conducted by means of surface flow visualization technique and Particle Tracking Velocimetry (PTV). Furthermore, analytical techniques of proper orthogonal decomposition (POD) are applied to reveal typical pattern of coherent structures.

著者

土屋 十圀 池田 駿介

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.42, pp.403-408, 1998-02-20 (Released:2010-08-25)

参考文献数

11

被引用文献数

1 1

---

The present paper deals with hydraulics in compound open channels with vegetation, the purpose of which is the application of the experimental results to planning and design of actual rivers. The experimental study was performed by measuring the resistance to flow in channel with artificial reeds and lateral velocity distribution at various design discharges. The laboratory tests indicate that the resistance coefficient is increased considerably (by 53%) even if the vegetation locates only at low banks. As an experimental technique, it was found that fine nylon-filament was the best to simulate flexible vegetation.

著者

冨永 晃宏 庄 建冶朗 内藤 健 松本 大三

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.49, pp.1009-1014, 2005-02-01 (Released:2011-06-27)

参考文献数

9

---

A traditional river structure, “Seigyu”, is a kind of spur dikes for protecting riverbank against erosion. Actual examples of Seigyu groins and their effects on bed protection were surveyed in the Ooi River. Experiments on flow structures and bed evolution were conducted in a laboratory flume with Seigyu models. The effectiveness of the groins was recognized on the deceleration of downstream flows and on the prevention from bed scour. The arrangement manner and the placing method of the groins were also investigated. A series of Seigyu groins is effective even for steep-slope flows but the erosion becomes very large beside groins. We compared the bed configuration around Seigyu groins with that around a group of rod roughness. The characteristics of resistance to flow for Seigyu groins is different from that for rod dikes because Seigyu groins have gabions near the bed. This fact makes different effects on riverbank protection.

著者

尾澤 卓思

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.37, pp.845-848, 1993-02-20 (Released:2010-06-04)

参考文献数

1

---

This report describes a survey of mole's tunnel in river bank. The situation of mole's tunnel in river bank has been hardly known until now. This survey is that the plaster water was put into the mole's tunnel in the old bank of the Chikugo river and after the plaster fixed, the bank was cut and opened.After that the depth of the tunnel and its extent were recorded. The data is valuable to study the influence of mole's tunnels in the aspect of leakage, piping and slope collapse of the river bank.

著者

木内 豪 神田 学 栗城 稔 小林 裕明

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.38, pp.381-386, 1994-02-28 (Released:2010-08-25)

参考文献数

4

被引用文献数

2 7

---

Growing cities have been deteriorating heat environment due to artificial coverage of the ground and artificial heat effluence. The authors focused on the watering on paved roads as one of elective and immediate measures against the situation and observed the elect on the micro climate in a city area in the last summer. The results showed that the difference in temperature and humidity at two points with and without watering were maximum 1.5 degree and 8%, respectively. In addition, the estimated heat balance at the points showed that the considerable latent heat and the lateral heat transport contributed to lower the surface temperature of the road due to watering.

著者

大成 博文 前田 邦男 松尾 克美 山原 康嗣 渡辺 勝利 石川 並木

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.46, pp.1163-1168, 2002-02-10 (Released:2010-06-04)

参考文献数

6

被引用文献数

2 7

---

New techniques for oyster cultivation at Hiroshima bay are investigated using sea water micro-bubbles.The present results indicate some new aspects that the device of sea water micro-bubble generated about 51/min air discharge. under the water depth of 10-15m. By generating micro-bubbles, the salinity of sea water in the surface layer increased about 13% and the water temperature decreased about 2°C in the oyster farm in summer. Finally, the oysters which had been named “Waka” about thirty years ago were restored to the original state by using sea water micro-bubble technique.“Waka oyster” grew up rapidly for about a half year and had a rich constituent of glycogen.

著者

後藤 仁志 林 稔 安藤 怜 酒井 哲郎

出版者

Japan Society of Civil Engineers

雑誌

水工学論文集 (ISSN:09167374)

巻号頁・発行日

vol.47, pp.547-552, 2003-02-10 (Released:2010-06-04)

参考文献数

11

被引用文献数

1 5

---

The Lagrangian model of solid-liquid two phase flow is proposed by combining the Moving Particle Semi-implicit (=MPS) method with the Distinct Element Method (=DEM). The governing equations of two fluid model is discretized by the MPS method, with the model of interparticle collision in solid phase based on the DEM. The relationships of present model with the previous Lagrangian model of a motion of single sediment particle and the non-Newtonian fluid model are discussed. The performance of the present model is investigated by simulating the dropping lump of mud into still water. By comparing the solutions of three models, such as the present model; the two fluid model by the MPS method without the DEM; and the MPS method with the passively moving solids module, the effect of cohesion of mud is reproduced well by the present model.