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Abe, Shota (Yachiyo Engineering Co., Ltd, Taito, Tokyo) | Kimura, Katsutoshi (Muroran Institute of Technology, Muroran, Hokkaido) | Nakoshi, Takao (Hokkaido Road Management Engineering Center, Sapporo, Hokkaido) | Yamamoto, Yasuji (Hokkaido University of Science, Sapporo, Hokkaido) | Murata, Yoshihiro (Civil Engineering Consultant Sapporo Branch, Sapporo, Hokkaido)
ABSTRACT The research reported here involved clarification of the process of wave-related abrasion on a slit-type seawall along a rocky coastline, with investigation of the movement characteristics of 100 kg of stones via hydraulic experiments with a model scale of 1/20. Abrasion damage was generally observed near the still water level with correspondence to the position with the highest collision ratio, which was higher for longer wave periods. The relationship between wave height and collision speed was clarified from analysis of video on stone movement patterns relating to wave action. The characteristics of flow patterns and overtopping waves were investigated up to design wave conditions via hydraulic experiments with a model scale of 1/40, and seawall abrasion was estimated as 10 mm/year (similar to the observation value) using an experimental formula based on local wave data. Damage repair was also proposed from the wave overtopping test results, with concrete filling of worn parts and placement of wave-dissipating blocks found to be an optimal approach. INTRODUCTION Deformation of concrete structures along rocky coastlines due to stone motion caused by wave action often progresses rapidly, seriously affecting seawall safety and the anti-wave performance of related background facilities. To elucidate the status of such abrasion, Watanabe, et al.(2013) researched concrete-block erosion along the Shimoniikawa coast of Japan's Toyama Prefecture and the Suruga and Numazu coasts of Shizuoka Prefecture, reporting larger abrasion volumes around an elevation of still water level (T.P. 0.0 m). Abrasion research conducted by Matsuda et al. (2007) regarding coastal bridge piers on the Hokuriku Expressway in Ishikawa Prefecture also revealed an abrasion rate of approximately 10 mm/year. Oide et al. (2018) further reported a risk of tunnel collapse along the Ogon route in the Hiroo area of Hokkaido due to ongoing abrasion to the lower levels of block masonry.
ABSTRACT A multi-piled oil pier is planned to be built in Bohai Sea. For such piled foundation structures in cold seas, ice loads on the piles are often considered as the dominant loads in design. A series of model tests were performed to evaluate the ice loads on the structure and the pile-group effect. Considering the ice conditions of the study sea area, in total, 6 tests were performed and the ice forces on each pile were measured under different test conditions. The test results and discussions are presented in this paper. INTRODUCTION With the rapid development of marine transporting and oil exploring activities, large number of oil wharfs have been built up on the shorelines of cold region seas in recent decades. For example, from 2005 to 2015 more than 10 large ports with big oil or gas wharfs were built along the shorelines of Bohai Sea, which is the northernmost sea of China. To achieve large water depth for giant oil transporting vessels, the oil loading terminal needs to be designed to extend to deep water area through multi-piled oil pier. This kind of structure consists of a series of piles and its upper structure (Fig. 1). Furthermore, these structures usually have incorporated batter piles to resist lateral loading, such as ship impact or environmental loads (i.e. wind load, wave load, seismic load or ice load). Ice loads on the piles are often considered as the dominant loads in design when such structures are located in cold seas. Mainly two types of models for estimating the ice load on single pile have been developed, i.e. analytical models and semi-empirical models. Various aspects of ice actions on multi-piled structures were prior investigated analytically and experimentally (Kato, 1983; Toyama, 1994). These experimental or theoretic studies have given some insightful investigations on the ice loads on multi-piled structures. It has been proven by many researchers that the key in determining ice loads on multi-piled structure is the evaluation of pile-group effect by which the ice load on single pile is reduced.
Hironori Wasada, senior vice president of JX Nippon Oil & Gas Exploration, highlights the ambitions and challenges facing the domestic and international operations of his company. What is the current status of the oil and gas industry in Japan? Japan imports almost 99.6% of its oil requirements, as we produce only 14,000 BOPD, which is less than 0.4% of our consumption. For gas, Japan produces about 3% of its consumption, with 97% of our consumption imported in the form of liquefied natural gas (LNG). The country is trying to reduce its energy export reliance, and the Japanese government is assisting and encouraging local companies to search for oil and gas offshore. Onshore fields in Japan are old and have started depleting, and recently a Japanese firm made a trial production of shale oil from an onshore oil field. In addition, the government is looking for alternative energy resources to meet growing local demand, and is currently looking at the commerciality of offshore methane hydrates. Also, several companies recently have been listed on the local stock exchange, which has put the industry under the scrutiny of investors who expect it to deliver revenue. Who are the major shareholders of JX Nippon? What major projects are you currently involved in? JX Nippon Oil & Gas Exploration Corporation is a business unit of JX Group, and is engaged in oil and gas development all over the world. We are very active in Japan, where development of local energy resources is the mission of Japanese companies. We are committed to continuing exploration activities in Japan, with the aim of contributing to a stable supply of energy. Currently, we are involved in exploration activities offshore Japan, and this includes the Sanriku and offshore Erimo blocks. Also, we hold a 100% interest in offshore blocks Shikoku, Nishi-kyushu, Sado, and Toyama Bay. The onshore Nakajo oil and gas field in Niigata Prefecture, Japan, is the domestic E&P base of JX Group. Our mission in the Nakajo field is to steadily supply natural gas to customers, including industries and local communities. How about investment outside Japan? NOEX (JX Nippon) currently operates in 14 countries. We are leading projects as operators in crude oil production in Vietnam, natural gas production in Malaysia, and exploration in the UK North Sea. We have also been part of a consortium producing oil in the United Arab Emirates (UAE) for more than 30 years. We are very active in several Asian countries, including Thailand, Myanmar, Vietnam, Indonesia, and East Timor. In Thailand, we will apply our own experience and technologies acquired through our operations in Vietnam to improve the efficiency of crude oil production at the Nang Nuan oil field in Block B6/27, where we hold a 40% interest with PTTEP Siam, the operator with a 60% interest in the field. In Vietnam, we are involved in Block 15-2, Block 05-1 b/c, and Block 16-2, while in Myanmar, we hold interests in Blocks M12, 13, and 14 and Block M11. We are also involved in LNG projects, including the Tangguh LNG project in Indonesia, and Papua New Guinea’s first LNG project, which is set to deliver its first LNG cargo in 2014.
Nagai, Toshihiko (Managing Director of Research Affairs, Port and Airport Research Institute Yokosuka, Japan) | Hiraishi, Tetsuya (Director, Marine Environment and Engineering Department, Port and Airport Research Institute Yokosuka, Japan) | Kwawai, Hiroyasu (Head, Marine Information, Division, Marine Environment and Engineering Department, Port and Airport Research Institute Yokosuka, Japan) | Kawaguchi, Koji (Senior Researcher, Marine Environment and Engineering Department, Port and Airport Research Institute Yokosuka, Japan) | Nihei, Akira (Director, Niigata Ports and Airports Investigation Center, Hokuriku District Infrastructure Bureau, Ministry of Land, Infrastructure, Transport and Tourism, Niigata, Japan) | Ohkama, Tatsuo (Director, Fushiki-Toyama Port Office, Hokuriku District Infrastructure Bureau, Ministry of Land, Infrastructure, Transport and Tourism, Toyama, Japan)
On February 24, 2008, a twin low pressure system caused very high wave condition on the whole coast of the Japan Sea. The Yorimawari- Nami, peculiar long period swells in the sea, entered Toyama bay and gave unexpected damage to the coastal and port areas. This paper describes the significant waves and spectrum profiles of the swells observed by the coastal wave observation network NOWPHAS. The wave records show that the peak significant wave height and period reached 9.92 m and 16.2 s at Toyama Station on a submarine peninsula in the bay. The shallow water wave simulation using the Boussinesq model tends to amplify the wave energy in some areas due to a peculiar bathymetry with submarine peninsulas and steep slopes in the bay, which is called Aigame in the district. INTRODUCTION On February 24, 2008, a twin low pressure system caused very high wave condition on the whole coast of the Japan Sea. The Yorimawari-Nami (Yoshida et al., 1986), sudden peculiar long period swell attack seen in the Toyama-bay coasts in the winter season, leads unexpected damages to the coastal and port areas. The Toyama-bay coastal area has experienced the Yorimawari- Nami attack once or twice every winter season. The Yorimawari-Nami phenomenon is supposed to be caused by winter monsoon in the northern Japan sea area (Nagai, 2002). But the event on February 24, 2008 was the worst one in recent decades. This paper, therefore, describes the significant waves and spectrum profiles of the swells observed by the Japanese coastal wave observation network NOWPHAS.
Otsuka, Koji (Department of Marine System Engineering, Osaka Prefecture University) | Ikeda, Tomoji (Research and development department, The General Environmental Technos Co., LTD) | Hayashi, Masatoshi (Research and development department, The General Environmental Technos Co., LTD)
ABSTRACT This paper presents a review of researches on environmental impact assessment for pumping-up and discharging deep ocean water, which was performed from 1999 through 2003 as a part of a national project organized by the New Energy and Industrial Technology Development Organization (NEDO). In this study, 13 investigation subjects were selected for the environmental impact assessment for large-scale deep ocean water utilization. Some results of the major subjects, such as CO2 emission, biological entrainment and impingement, physical/chemical water quality, eutrophication, phytoplankton growth, red tide occurrence and seaweed growth including seaweed bed recovery are shown in this paper. INTRODUCTION Deep ocean water (DOW) is cold, nutrient-rich and pathogen-free seawater found at depth of several-hundred meters or lower. The DOW has attracted special interest as a renewable resource for energy and marine primary production (Fast, 1991), and also been focused as the useful material for fresh water production, air conditioning, refrigeration, and so forth (Van Ryzin and Leraand, 2000). The multiple productions based on this enormous renewable resource may result environmental sustainability and economic viability (Daniel, 1992). In Japan, several DOW utilization facilities are operated by research laboratories (Otsuka, 2001). Various DOW applications and their integrated systems are investigated in these facilities. In addition, the pumped-up DOW is commercially distributed, and used for many products, such as drinks, foods, medical and health care uses, cosmetics, etc. Two national DOW projects for large-scale (105~106td-1) applications, which were driven by the New Energy and Industrial Technology Development Organization (NEDO) and the Marino-Forum 21 (MF21), have recently been operated (Kadoyu, Eguchi and Takeda, 2003; Takahashi and Ikeya, 2003). The NEDO project focuses on the optimum design of integrated DOW utilization systems for cooling steam-power plant units (Kadoyu, Eguchi and Takeda, 2003).
ABSTRACT The authors have proposed the procedure which can estimate the design earthquake load on a structure in the Sea of Okhotsk and developed the single purpose code base on the Monte Carlo simulation. The authors extended the code to be able to handle any kind of structure in an ice-covered water. A brief description of the extended code will be first presented in the paper. The assumptions will be described to make easier to judge the extended code. Results of some trial calculations will be presented and some suggestions will be made based on the limited result. INTRODUCTION The existing design guidelines for arctic structures such as API (1995) and CSA (1992) postulate special considerations for the estimation of design loads on a structure in an earthquake susceptible region. This postulation implies that the ice load shall affect the design earthquake load, or the earthquake load shall affect the design ice load. However these guidelines do not specify how to handle this issue. It is obvious that the simple sum of the design earthquake and ice loads both corresponding to N years return period shall give an overestimated design load. The authors considered that an earthquake load may be magnified to some extent by the ice-structure interaction during the earthquake. The authors proposed the numerical procedure based on the Monte Carlo simulation to throw a light on the issue (Toyama et. el., 2001, Kato, et. al, 2001). The proposed procedure seemed to be promising, but no more discussion, such as the effect of annual frequency of earthquake, the effect of design earthquake acceleration and so on, could be made. It was because that the numerical code developed could handle a limited situation. The code could handle one earthquake hazard curve, one ice season model and one structure.
Kanamaki, Seiichi (Department of Technology Promotion, Fuyo Ocean Development and Engineering Co. Ltd) | Uemura, Yasuharu (Department of Technology Promotion, Fuyo Ocean Development and Engineering Co. Ltd) | Ohmura, Hisaaki (Department of Technology Promotion, Fuyo Ocean Development and Engineering Co. Ltd) | Suzuki, Tatsuo (Ashcrete Corporation) | Honda, Yoichi (Ouchi Ocean Consultant, Inc) | Oshima, Yuko (Environmental Technical Section, PASCO Environmental Science Institute) | Yasuda, Ichiro (Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo)
ABSTRACT: The Marino-Forum 21 initiated the research project on development of fishing grounds by utilizing Deep Ocean Water (called DOW here after) of 200 m deep. We plan to enhance the component of nutrient salts in the sea area concerned by discharging DOW into the euphotic layers aiming ultimately at enabling phytoplankton biomass to increase. Our group is responsible for biological sector to examine the change in phytoplankton biomass. The "sea area fertilizing apparatus: TAKUMI" has already been produced. Out of several applicable waters, we finally decided the site to be at the core part of gyre formed in the Sagami Bay to meet the purpose. The reason for this was that if DOW is poured at around center of the gyre, the dispersion of nutrients would assumedly be restrained. We are now further studying the technology for tracking the transfer and diffusion area of discharged. We present here the current state of our research and the future plan. INTRODUCTION The fertilization plan of the sea area by means of DOW was first proposed by Naka shima and Toyota in 1984 in Japan(Nakashima and Toyota 1989). After the proposal, the Science and Technology Agency constructed the equipment called "HOYOU" which en ables to pour DOW over the sea surface. By utilizing the HOYOU, the field experiment was carried out for the first time in 1989 and 1990 in Toyama Bay (Kitani and Nagata 1989, Iseki et al. 1994). However, the effect of fertilization was not detected, since the quantity of DOW applied was too small with about 26,000 ton s/day. A new technology development project was then initiated by the Ministry of Economy, Trade and Industry Agency of Natural Resources and Energy in 1999 for 5 years aiming at developing the rational utilization of marine resources.
Ikeda, Tomoji (Research and development department, Kansai Environmental Engineer Center Co) | Hayashi, Masatoshi (Research and development department, Kansai Environmental Engineer Center Co) | Otsuka, Koji (Department of Marine System Engineering, Osaka Prefecture University)
ABSTRACT This paper presents a brief review of recent researches on environmental impact assessment for pumping-up and discharging deep seawater, which is performed as a part of a national project driven by Japan Ocean Industries Association (JOIA). These researches focus on several environmental effects, such as biological entrainment, CO2emission from power plant, cooling water discharge, and fertilization for phytoplankton and seaweed. The results of these assessments suggest that dominant environmental effects of pumping-up and discharging deep seawater are environmental benign, e.g. fertilization, and development of a proper discharging system is important. INTRODUCTION Deep seawater is cold, nutrient-rich and pathogen-free seawater found at depth of several-hundred meters or lower. The deep seawater has attracted special interest as a renewable resource for energy and marine primary production (Fast, 1991), and also been focused as the useful material for fresh water production, air conditioning/refrigeration, and so forth (Van Ryzin et al., 2000). The multiple productions based on this enormous renewable resource may result in environmental sustainability and economic viability (Daniel, 1992). In Japan, several deep seawater research laboratories and utilization facilities are operated, and over ten facilities are planned (Otsuka, 2001). These facilities investigate various deep seawater applications and their integrated systems. In addition, the pumping-up deep seawater are commercially distributed, and used for many deep seawater merchandises, such as drinks, foods, medical and health care uses, cosmetics, etc. Two national deep seawater projects for large-scale applications, which are driven by Japan Ocean Industries Association (JOIA) and Marino-Forum 21 (MF21), have recently started. JOIA project focuses on optimum design of an integrated deep seawater utilization system with cooling for steam-power plant (JOIA, 2000, 2001). In MF21 project, a prototype artificial upwelling machine is developed for enhancement of marine primary production (Ogiwara et al., 2001, Ouchi et al., 2001).
ABSTRACT: This paper presents a brief review of recent researches on deep ocean water applications in Japan. Firstly, various applications using deep ocean water, such as ocean thermal energy conversion, fresh water production, air conditioning/refrigeration, mariculture, agriculture, are summarized. Then, major deep ocean water facilities in Japan are introduced. Finally, two national projects, which are driven by Japan Ocean Industries Association (JOIA) and Marino-Forum 21 (MF21), are briefly presented. INTRODUCTION World population has rapidly increased since the industrial revolution. At this rate, population will become 10 billion by the end of the first quarter of this century, meaning severe consequences for future energy and food securities. Improvement of the living standard in developing nations raises energy demand worldwide. However, increase of conventional power plant based on fossil fuels will make worse of global environment represented by global warming and acid rain. Therefore the world's energy economy is beginning to move away from fossil fuels toward renewable energies, such as solar, wind, geothermal, biomass and several ocean energies. Strengthening the international regulation for CO2 emission rate would accelerate this trend. World's crop yields have drastically increased in recent years, but the growth saturated at around 10 years ago due to the limit of terrestrial soil capacity. The total fisheries catch in the world reaches 100 million tons in 1989 and has stagnated since then, because many fishing areas and species have reached their maximum sustainable yields. This means that any new technologies for sustainable primary production are required. Deep ocean water (DOW) is cold, nutrient-rich and pathogen-free seawater found at depth of several-hundred meters or lower. The DOW has attracted special interest as a renewable resource for energy and marine primary production, and also been focused as the useful material for fresh water production, air conditioning/refrigeration, and so forth.
ABSTRACT: The authors have investigated the deterioration phenomena, conservation and restoration of stone cultural heritages from the viewpoint of rock mechanics. This paper shows the state of the art of deterioration examinations, conservation and restoration of stone Buddha images in Japan. I. INTRODUCTION A word of stone cultural heritages recalls a stone Buddha image and/or a structure made of stone to our minds. Stone Buddha images, which were carved in rock mass, are one of the stone cultural heritages whose conservation and restoration works are difficult. Because stone Buddha images are usually in contact with the ground, they are affected by the underground water. Many stone Buddha images are seen in various parts of Japan, especially in Oita prefecture in Kyushu Island. There are about 400 stone Buddha images at 83 points in Oita prefecture (Oita City Board of Education 1996), and the Usuki Stone Buddha images (Photo I), which are distributed in the southeast of Oita prefecture, are the most famous among them (figure I). A group of the Usuki Buddha Stone Images was designated as a national important cultural property in 1962. Subsequently, it was also designated as a national treasure in 1995. The Usuki Stone Buddha Images have therefore two faces, i.e. cultural properties and arts. The Usuki Stone Buddha Images, which were sculptured in the later Heian period (in the 12th century), are mainly made of melted tuff formed by an ancient explosion of Mt. Aso. The degree of cementation of melted tuff is relatively small, and it is therefore not enough to strengthen the surface of rock mass, but necessary to reinforce from the side of structural mechanics of rock mass when melted tuff is weathered and deteriorated. Moreover, in case of conservation works, conservation methods should be investigated from every point of view as for the deteriorated stone Buddha images. 2. HISTORY Of STONE BUDDHA IMAGES IN JAPAN What is a stone Buddha image? First of all, we have to make clear as to what is a stone Buddha image. Nevertheless, it is difficult to define a stone Buddha image. A dictionary defines a stone Buddha image as a Buddha carved in stone, or a Buddha made of stone. Talking about stone, some stone Buddha images are sculptured in rock faces, and others are scraped in individual stones. In Japan, the first Buddha image was made in Nara period (in the 8th century). Consequently, the oldest stone Buddha images can be seen in Nara prefecture (Koushin Gathering for Friendly Discussion 1998). When the Heian period (between the late 8th and the late 12th century) came, many stone Buddha images were made all over the country. Excepting Shiga prefecture, there are few stone Buddha images in the former term of the Heian period. As Usuki, Kumano and so on were made numerously in Oita prefecture, and present grand sights. There are also some other stone Buddha images in Toyama and Tochigi prefecture.