Construction Of Artificial Islands Research Articles

The Development of Offshore Artificial Island Construction and Application of Key Hydrodynamic Technologies in China ——Take Haihua Island Project as an Example

In recent years, with the development of China’s coastal waters and coastal urban space expansion needs, the construction of artificial islands on the sea has achieved rapid development. In order to allow it to further promote the development of Marine economy in our country, relieve the contradictions of land and environmental pressure and maintain the Marine ownership plays an important role in our country, research from the review summarizes the development of China offshore artificial island and the technical characteristics of typical artificial island has been built and under construction engineering examples, the paper introduces the construction and offshore artificial island development present situation, and sums up the construction of artificial islands facing the core issues. At the same time, based on the analysis on the status at present domestic offshore artificial island, points out the key technology of the construction of the island, and in the sea flower island project carried out by the series water power project as an example, a detailed discussion on wave flow elements, the seabed sediment, as well as the influence on surrounding channel water exchange, and the three dimensional seepage flow, etc. The research achievements of the project. The research points out that the future construction of artificial islands should return to rationality and science and pay more attention to the integration of natural ecology and environment.

Safety Management in Sea Reclamation Construction: A Case Study of Sanya Airport, China

Urbanization has increased the burden on land resources. Artificial island construction has been proven as an effective method for addressing these land resource problems; however, few studies have been conducted on the safety of sea reclamation construction. This paper proposes a systemic approach to the complete safety management process in sea reclamation engineering, including safety system design, analysis, control, and assessment, using the Sanya Sea Reclamation Airport, Hainan Province, China, as a case study. A total of 145 steel cylinders must be vibrated and sunk into the seafloor to create a 9 km quay wall. Owing to their large size, the steel cylinders have been divided into different segments, and an assembly jig is employed to ensure a safe production process. Considering the hazardous working environment in sea reclamation construction, a numerical analysis is conducted to investigate the safe repertory of these steel cylinders and verify the reliability of the selected scheme for their transportation. Finally, control measures are adopted to ensure a safe vibration and sinking procedure for the steel cylinders. The proposed approach could be used to provide safety management guidelines for artificial island engineering and construction.

Factors affecting particle breakage of calcareous soil retrieved from South China Sea

Calcareous soil is originated from marine biogenic sediments and weathering of carbonate rocks. The formation history for calcareous sediment includes complex physical, biological and chemical processes. It is preferably selected as the major fill materials for hydraulic reclamation and artificial island construction. Calcareous sands possess inter pores and complex shape are liable to be damaged at normal working stress level due to its fragile nature. Thus, the engineering properties of calcareous soil are greatly affected by its high compressibility and crushability. A series of triaxial shear tests were performed on calcareous sands derived from South China Sea under different test conditions. The effects of confining pressure, particle size, grading, compactness, drainage condition, and water content on the total amount of particle breakage for calcareous soil were symmetrically investigated. The test results showed that the crushing extent of calcareous sand with full gradation was smaller than that a single particle group under the same test condition. Large grains are cushioned by surrounding small particles and such micro-structure reduces the probability of breakage for well-graded sands. The increasing tendency of particle crushing for calcareous sand with a rise in confining pressure and compactness is confirmed. It is also evident that a rise in water content enhances the amount of particle breakage for calcareous sand. However, varying tendency of particle breakage with grain size is still controversial and requires further examination.

Spatio-temporal variation of subtidal macrobenthic fauna and the ecological assessment of Longkou Artificial Island construction in Bohai Sea, China

To evaluate the status and changes of macrobenthic communities related to the construction of the Longkou Artificial Island (LAI) in the Bohai Sea, China, four annual surveys were conducted from 2010 to 2013. Significant changes on environmental variations and macrobenthic communities were observed in 2013 after the LAI construction a couple of years later. The changing environment was primarily presented by lower values of pH, dissolved oxygen (DO), organic material (OM) percentage, and higher salinity, suspended particulate matter (SPM) concentration and oil concentration. The main dominant species shifted from Polychaeta taxa in 2010 to Mollusca taxa in 2013 due to the changes of environmental variables. An apparent miniaturization tendency in body size of macrobenthic species was presented from 2010 to 2013. The biodiversity indices increased yearly from 2010 to 2013. However, inter-site homogenization was observed in both the community structure and health status. Multivariate AZTI Marine Biotic Index (M-AMBI) analysis showed that the health status of stations changed depending on its original status and distance to the LAI. However, no significant differences were found in the spatial distribution of either environmental variables or abundance, biomass and biodiversity of macrobenthic communities. All the results will provide a basis for the long-term ecological assessment of reclamation.

Analysis of Coastal Zone Data of Northern Yantai Collected by Remote Sensing from 1990 to 2018

Using remote sensing images of different time phases from 1990 to 2018, the surface coverage information of northern Yantai (coastline, 2 km from coastline to land) was extracted by means of average high tide line and visual interpretation. The end point change rate (EPR) and linear regression rate were used to study the coastline change rate, the fractal dimension of the coastline in the study area was analyzed, and the change of the type of coastal surface cover was analyzed by the transition matrix. The results show that: (1) Form 1990 to 2018, a significant trend of a continuous increase in the total length of coastline was observed with an increase of 181.08 km (43.18%). In the study area, the coastline of Laizhou had the greatest change rate with an EPR value of 33.67 m/a, whereas the coastline of Laishan had the smallest change rate with an EPR value of 0.30 m/a. (2) Over the past 30 years, with the rapid economic development of Yantai and the ensuant urbanization, the total surface area of the coastal zone in the study area has increased by 144.94 km2, mainly in the areas covered by structures and forests/grasses, by 112.96 km2 and 96.08 km2, respectively, while the areas of desert/bare land and water have decreased by 92.26 km2 and 12.32 km2, respectively. (3) The changes among different types in the study area were clear, mainly from desert/bare land, cultivated land, and building areas to forests/grasses cover and structures. The change areas were mainly concentrated in Laizhou, Longkou, Zhifu, and Penglai. Frequent human activities are an important factor affecting the continuous expansion of the coastal areas of Jiaodong Peninsula to the sea. Aquaculture, coastal construction, construction of artificial islands, and expansion of port terminals have seriously affected the sustainability of ecological resources in the coastal areas. At the same time, the changes in the ecological environment in the coastal zone will have a greater impact on the health of the coastal zone.

International Law as an Adaptation Measure to Sea-level Rise and Its Impacts on Islands and Offshore Features

Abstract Climate change-induced sea-level rise will result in the partial or complete inundation of low-lying coastal areas and insular features. The consequences of this include the loss of baselines from which maritime zones are established. The loss of baselines raises a number of legal questions, in particular concerning the legal status of maritime entitlements and in some cases the potential loss of statehood. Solutions proposed include maintaining existing baselines or outer limits of maritime zones, or the construction de novo of artificial islands. This article examines the current state of international law under the international climate-change regime and the law of the sea in relation to adaptation and adaptive measures, such as maintaining of baselines, island fortification and the construction of artificial islands. In addition, the article explores the question as to whether measures such as maintaining baselines would constitute adaptive measures under the existing climate-change regime.

Hybrid Warfare and Deniability as Understood by the Military

Russia and China are terraforming the maritime environment as part of their warfare. In both cases the actions are illegal and the performance is offensive to its actual nature. In the case of China, the practice is construction of artificial islands in the South Chinese Sea and in the case of Russia it is about the infamous bridge built over the Kerch strait, Ukraine. Neither Russia nor China expects an armed conflict with the West in the near future. That is a reasonable assumption, which is weaponized at the political-strategically level. The attack of this weaponized situation is that the trust in the West. Primarily the EU (European Union) and NATO (North Atlantic Treaty Organization), is eroded for every day which these countries challenges the international system which the western democracies say that they present and defend. China and Russia offer their authoritarian systems as a replacement and there are a lot of pseudo-democratic or even out-right authoritarian regimes on the sideline watching this challenge unfold. The article highlights the difference for the NATO-countries in logic of practice when it comes to the political social field on one hand and the military political field on the other hand. The article uses material from a previously unpublished survey made on NATO-officers then attending courses at NATO Defense College (NDC).

СИТАЛЛЫ ИЗ МЕСТНОГО СЫРЬЯ ДЛЯ ПРОИЗВОДСТВЕННЫХ ИННОВАЦИОННЫХ ИНФРАСТРУКТУР С ВЫСОКОЙ ТЕХНИКО-ЭКОНОМИЧЕСКОЙ ЭФФЕКТИВНОСТЬЮ В ЭКСТРЕМАЛЬНЫХ УСЛОВИЯХ КРАЙНЕГО СЕВЕРА

Актуальность исследования обусловлена проблемами эффективности освоения полезных ископаемых Заполярья за счет отказа от ввозимых за тысячи километров строительных материалов (бетонных изделий, кирпича и т. п.). Максимальная удаленность от промышленно-урбанизированных центров в сочетании с крайне суровыми природно-климатическими условиями Крайнего Севера значительно влияют на экономику добычи и экологию территории, где стоимость строительных материалов доходит до 70 % себестоимости нефти и газа. Выход на шельфы арктических морей России и других стран требует инновационных материалов и прорывных технологий, включая строительство искусственных островов и подводных сооружений на шельфе. Для реализации таких прорывных технологий необходимы материалы и конструкции, обладающие многократно большей прочностью и долговечностью. Цель исследования: разработать на основе сырья Полярного Урала многофункциональные материалы класса «сикам» с уникальным сочетанием физико-механических и химических свойств для передовых технологий. Объекты исследований: отвальные горные породы базитового ряда золоторудных месторождений Полярного Урала, метасиликатные расплавы, стекла и ситаллы. Методы исследований: теоретические и экспериментальные исследования исходных сырьевых материалов, расчет состава шихты для метасиликатных ситаллов – нового класса «сикам» (СКС), методы определения основных технологических параметров, изучения основных свойств продукции, методы создания новых инновационных строительных конструкций, методы обоснования технико-экономических показателей. Химический состав исходного сырья определен масс-спектральным методом с индуктивно связанной плазмой. Результаты исследований. Обоснованы исходные составы и установлены физико-химические свойства петроситаллов класса «сикам» из местного сырья золоторудных месторождений Полярного Урала. Показана экономическая эффективность и экологическая целесообразность производства материала на месте с использованием дешевого энергоносителя (попутного газа) в сравнении с ввозимым железобетоном. В особых условиях Арктики этот материал незаменим для производства свайно-эстакадной дорожной конструкции и строительства на ее основе долговечной транспортной инфраструктуры, промышленных и гражданских объектов в условиях вечной мерзлоты и арктического шельфа.

Energy, Trade and Geopolitics in Asia: The Implications for Canada

Canada’s growing interest in trade with countries in the Indo-Pacific region corresponds with an ominous growth in geopolitical instability and insecurity in that part of the globe. With Indo-Pacific hunger for oil expected to soar – especially in China, where demand will translate to 80 per cent of imports in 10 years – Canada needs to develop policies to deal with the region’s turbulent realities. The Indo-Pacific comprises countries in South Asia and Southeast Asia, and includes such unstable and unpredictable players as North Korea and Pakistan, both of which have nuclear weapons and long-simmering border tensions. India is an emerging economic and military rival to China. In the next 20 years, China and India are expected to lead the global demand for gas as coal consumption continues to decline, and Canada has a stake in this prosperous future. Along with territorial squabbles in the region, Canada will have to deal with complex issues such as terrorism, human trafficking, transnational crime, piracy and cyber-crime, as well as the struggle for global dominance between China and the U.S. One key area for potential conflict is China’s recent construction and militarization of artificial islands in the South China Sea. The Canadian government’s new military strategy, Strong, Secure, Engaged does little more than make a plea for peace and the rule of law in the South China Sea. However, more trade crosses the Pacific Ocean from Canada than crosses the Atlantic. And with Canada signing on to the Comprehensive and Progressive Trans-Pacific Partnership (CPTPP), the region’s troubles will need to be resolved by more than good intentions on paper. Canada must shift more diplomatic, security and military resources to the Indo-Pacific; otherwise, its efforts will be spread too thinly to be effective in the region. Trade, especially through a major route like the Strait of Malacca, could easily be disrupted by any one of a number of disputes, such as a conflict between China and Taiwan or if historic resentments boil over among competing territorial claimants in the region. Thus, Canada needs to step up and reaffirm its security commitments to the Association of Southeast Asian Nations (ASEAN) as a partner in the region. Participating in maritime exercises and Freedom of Navigation (FON) operations would also help to reinforce to countries in the region the importance of abiding by international law. Meanwhile, Canada should set aside for now any intentions to negotiate a free trade agreement with China. China does not share some of Canada’s key trade and security goals and its aggressive behaviour in the South and East China Seas clearly signal that now is not the time to talk about a trade pact. China must demonstrate that it is willing to take a more cooperative approach to resolving trade and security issues in the Indo-Pacific and to support and respect the rule of law in the region. Canada has the potential to become a reliable, stable source of energy for Indo-Pacific countries. There is also an opportunity for provinces such as Alberta to strike their own strategic deals to provide energy resources to countries in that region, in return for trade and investment benefits. However, while investing at home in the necessary infrastructure and export capability to expand its role, Canada must also strive to bring its own unique approach to enhancing regional and energy security in the Indo-Pacific.

Environmental Issues in the South China Sea: Legal Obligation and Cooperation Drivers

Recently, we have been witnessing a critical level of a the degradation of the marine environment and depletion of fish stocks in the South China Sea. This has many adverse consequences on the politics, economics of the countries in the region as well as on the socio-economic life of the coastal population. One of the activities that has been causing serious damage to the marine environment and living resources of the South China Sea is the large-scale land reclamation and artificial island construction undertaken by China in the Spratly and Paracel islands recently. These activities have caused severe harm to the precious coral reef environment and thus, violated the obligation to preserve and protect fragile ecosystems and the habitat of depleted, threatened or endangered species under the international law of the seaThe paper explores the impact of China’s large-scale land reclamation and artificial island construction activities on the marine biodiversity of the South China Sea, explains what the legal obligation under the international law of States to protect and preserve the marine environment is and suggests a number of options in order to bring a halt to such activities and restore the damaged marine ecosystem. The paper puts particular emphasis on the cooperation drivers torwards a healthy, prosperous and peaceful South China Sea, which also contribute to the management and possibly, resolution of the current disputes in this region.Keywords: marine environmental issues, legal obligation, cooperation drivers, large-scale reclamation, artificial islands, blue solutions and fragile ecosystems.

Morphological changes in the Qinzhou Bay, Southwest China

Morphological change in the Qinzhou Bay (QZB), southwest China, has been studied, using bathymetric charts and remote sensing data. Historical admiralty charts were digitized and analyzed in a Geographical Information System (GIS) environment to provide quantitative estimates of underwater topography changes for exploring the accretion-erosion characteristics from 1960s to 2010s. Multi-temporal satellite images have been used to analyze the coastline developments. The results showed that the bathymetry and coastline of QZB changed dramatically in recent decades. The subaqueous area decreased by about 8% in the study area during the last 50 years, mainly due to coastal land reclamation. The average growth rate of the coastlines was 2.07 km/yr. between 1978 and 2013 with natural curvy coastlines being replaced by straighter artificial shorelines. During the period from 1960s to 1990s, the evolution of QZB was mainly governed by natural factors with slight deposition or erosion in the deep troughs. From 1990s to 2010s, intensive large-scale human activities, such as port building, channel dredging and artificial island construction became the main causes affecting morphological changes in the QZB. Approximately half of the underwater terrain had undergone significant changes (greater than ±0.5 m), and the proportion of deposition area accounting for 32.26% of the subaqueous area, about twice more than erosion area. Large scale reclamation projects have made dramatic negative impact on coastal natural ecosystem. Integrated coastal zone management need to be carried out to maintain the balance between economic development and ecological health.

Geopolitical and environmental study of artificial islands in the Persian Gulf (from the perspective of international law)

According to the Convention on the Law of the Sea 1982, constructing artificial island is permitted and countries can construct artificial islands in their own territory. Constructing artificial islands in the Persian Gulf area makes the countries in the region, especially Iran, to pursue the issue with more sensitivity. According to data dissemination principle of International Environmental Law, the countries that construct artificial islands should notify other states regarding construction and properties of their own artificial islands. Today, artificial island construction is being increased and this has caused many environmental crises including increase of water darkness and pollution and transport of coastal sediments. In this study, the destructive results of constructing artificial islands in the Persian Gulf environment, the effect of development of new land space from geopolitical view, and also constructing artificial islands from the viewpoint of International Law of the seas are being reviewed. Moreover, according to the fact that the notion of governance in modern International Law have been modified regarding the use of environment and sustainable development, the states will have limited right to construct artificial islands.

Experimental investigation of monochromatic wave transformation characteristics over the coral reefs

Due to the shallow water depth on the coral reef flat, most of the incident wave energy is dissipated by waves breaking on the frontal reef slope. However, extensive damages have been occasionally reported in low-lying coastal areas fronted by coral reefs during storms. It has long been known that waves breaking on a reef will cause wave set-up on the reef top. Wave set-up may be significant in determining water levels on coral reefs particularly in micro tidal environments. So it is important for the design and the stability of reef top structures. With the construction of artificial island in South China Sea, coral reefs are becoming a very popular research topic now. Laboratory experiments are carried out on an idealized platform reef in a wave flume located in the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian. The flume is 60 m long, 4 m wide and 2.5 m deep. The reef model consists of a reef face with a slope of 1:1 and a horizontal reef flat with 8.6 m in length. The reef flat is built 1.80 m high above the flume bottom. The water depth in front of the reef model is from 1.80 to 1.90 m, so the submergence of the reef top is from 0 to 10 cm. The water surface elevations and wave set-up over the reef top are measured using the wave gauges. The experimental results show that when waves propagate from deep water to the shallow water on the reef face and reef top, wave shoaling and wave breaking happen over the reef face or reef top. When ( η ¯ r + d r ) / H 0 > 0.7 , wave breaking occurs over the reef top, while for ( η ¯ r + d r ) / H 0 <0.7, wave breaking can be observed on the reef face. It should also be noticed that wave breaking may happen over the reef face when 0.7 ( η ¯ r + d r ) / H 0 As we expected wave set-up increases with the increasing wave heights and the decreasing submergence, while the wave periods have a complicated influence on the wave set-up. Our study indicates that wave set-up reaches the maximum value at T =1.75 s. The relationship between the relative wave set-up and relative submergence of the reef top is compared with the theoretical relationship of Gourlay and other available experimental data. In order to include the effect of wave-generated flow in Gourlay′s equation, a small value of the wave energy dissipation factor K p in the Gourlay′s equation is recommended. In our experiment, K p is different for the different submergence over the reef top. When ( η ¯ r + d r ) / H 0 0.5 or ( η ¯ r + d r ) / H 0 >0.8, K p is advised to be 0.35; while 0.5 ( η ¯ r + d r ) / H 0 0.8 , K p is suggested to be 0.50.

Международно-правовой режим искусственных островов и иных стационарных конструкций в море

Introduction. The 1969 Report of the UN General Secretary noted that 125 fixed platforms were used in offshore areas for the purpose of oil industry. “The International Law of the Sea” (Vol. 1 and 2) published in UK in 1994 provides that “approximately 6000 fixed platforms have been installed in offshore areas throughout the world”. In 2014 only in the area of the OSPAR Convention, 1992, more than 1300 offshore constructions were installed. As for January 2018, the majority of these constructions are in the North Sea (184), the Gulf of Mexico (175), the Persian Gulf (159), and offshore of Far East Asia (152) and Southeast Asia (152). In the other regions this number varies from 3 to 88, while the Canadian Arctic has the smallest number of offshore constructions limited to just 1 object. Accordingly, the issues of interpretation of UNCLOS articles on legal regime of artificial islands and other fixed structures at sea are becoming more pressing. Moreover, the interstate relations, regarding construction of artificial islands in offshore areas, need relevant legal framework to be in place, taking into account the constant growth of economic and military “competition” among countries, as well as the development of science and technologies applicable to offshore construction. Materials and methods . This paper dwells upon the international treaties and other legal instruments, which rely upon the terms “artificial islands”, “installations”, “structures” at sea for regulating relations among States and between States and other international law subjects. The materials for this paper are also commentaries of the UNCLOS, interpretation of the relevant articles of 1958 Geneva maritime conventions, applicable resolutions of the International Maritime Organization, and also definitions of the conventional terms suggested by scholars. The methodological basis of the research consists of general scientific and specific methods, including comparative method. Research results . Most specialists in the law of the sea who research similar topics dwell upon their personal definitions of the conventional terms mentioned above. Such specialists correctly note that the absence of such definitions in UNCLOS makes it difficult to interpret and apply relevant articles in a proper way. Meanwhile, the necessity for such interpretation and application is of practical value because such terms of UNCLOS relate firstly to relevant rights and jurisdiction of coastal and other States in maritime areas where artificial islands, installations and structures are used, including the territorial sea, the EEZ and the continental shelf. Nevertheless lots of different definitions of such terms suggested by scholars make it even more difficult to interpret and apply the rules of UNCLOS on artificial islands, installations and structures, including such sensitive areas of interstate relations as safety at sea and protection of the marine environment. Discussion and conclusions . The authors of this paper do not support any classification or definition of “artificial islands”, “installations” or “structures” or any other definition of other specific words used in UNCLOS for such terms. Instead the authors bring arguments to legal delineation of artificial islands from any other permanent structure at sea independently of the fact which particular word is used in UNCLOS for describing such a structure in a relevant article (“installations”, “structures”, “devices”, “equipment” etc.). It is argued in this paper that such legal delineation is caused by a difficult and comprehensive balance of interests achieved during the III Conference on the Law of the Sea, and such interests relating to economic, military, environmental interests of States, coastal and non-coastal, firstly in the EEZ and on the continental shelf.

Geopolitical and Environmental Study of Artificial Islands in the Persian Gulf (From the Perspective of International Law)

According to the Convention on the Law of the Sea 1982, constructing artificial islands is permitted and countries can construct artificial islands in their own territory. Constructing artificial islands in the Persian Gulf area makes the countries in the region, especially Iran, to pursue the issue with more sensitivity. According to the data dissemination principle of International Environmental Law, the countries that construct artificial islands should notify other states regarding the construction and properties of their own artificial islands. Today, artificial island construction is being increased and this has caused many environmental crises including an increase of water darkness and pollution and transport of coastal sediments. In this study, the destructive results of constructing artificial islands in the Persian Gulf environment, the effect of the development of new land space from geopolitical view, and also constructing artificial islands from the viewpoint of International Law of the seas are being reviewed. Moreover, according to the fact that the notion of governance in modern International Law has been modified regarding the use of the environment and sustainable development, the states will have a limited right to construct artificial islands.

Numerical Analysis of Soil Settlement Prediction and Its Application In Large-Scale Marine Reclamation Artificial Island Project

Abstract In an artificial island construction project based on the large-scale marine reclamation land, the soil settlement is a key to affect the late safe operation of the whole field. To analyze the factors of the soil settlement in a marine reclamation project, the SEM method in the soil micro-structural analysis method is used to test and study six soil samples such as the representative silt, mucky silty clay, silty clay and clay in the area. The structural characteristics that affect the soil settlement are obtained by observing the SEM charts at different depths. By combining numerical calculation method of Terzaghi’s one-dimensional and Biot’s two-dimensional consolidation theory, the one-dimensional and two-dimensional creep models are established and the numerical calculation results of two consolidation theories are compared in order to predict the maximum settlement of the soils 100 years after completion. The analysis results indicate that the micro-structural characteristics are the essential factor to affect the settlement in this area. Based on numerical analysis of one-dimensional and two-dimensional settlement, the settlement law and trend obtained by two numerical analysis method is similar. The analysis of this paper can provide reference and guidance to the project related to the marine reclamation land.

China's artificial islands in the south China sea: geopolitics versus rule of law

China’s construction of artificial islands during last few years has raised concerns about militarisation of the South China Sea threatening stability and security for littoral countries. China claims over 80 per cent of the South China Sea and it is building landing and garrison facilities over geographical features classified as rocks and coral reefs. China's claims are grounded on their supposed discovery and occupation of these features since antiquity. Other claimants, like the Philippines, Vietnam, Malaysia, Taiwan, Brunei and Indonesia, have their own historical narratives and cite articles of the UN Convention on the Law of the Sea (UNCLOS) to justify their sovereignty over part of this disputed maritime region. This multilateral nature of dispute makes it extremely complicated and China's increasingly assertive policies have further compounded it. Accordingly, several nations, including United States, have raised alarm regarding freedom of navigation across the South China Sea. It in this backdrop of rising tensions that this article examines these multiple narratives and what UNCLOS and the Permanent Court of Arbitration say in clarifying the legality of maritime rights to crystal gaze likely future trajectories. However, this study also recognizes that while UNCLOS remains at the core of maritime dispute settlement, it is the evolving geopolitics of Asia that will go a long way in guiding both the interpretation of UNCLOS as also state responses in terms of their proposals for joint development or unilateral strategies.

초장대 해저터널의 공사중 덕트 접속부의 누풍 성능 개선에 관한 연구

초장대 해저터널의 건설은 건설공간의 제약 및 건설비용 측면에서, 공사중에 사용되는 환기 시스템 설치에 유리한 조건을 갖고 있지 않다. 공사중 환기시스템을 제공하기 위해, 환기갱이 설치되는 인공섬들이 해저터널의 루트를 따라서 일부위치마다 건설됨으로써, 건설 비용이 많이 소요된다. 따라서 이러한 인공섬의 수를 최소화하는 것이 경제적으로 필요하다. 그러나 이것은 환기갱 사이의 거리가 더 길어지게 되므로, 필요한 환기풍량을 이송하기 위한 높은 팬 압력으로 인해 환기 덕트 접속부에서 누풍이 더 많이 발생하게 된다. 선행 연구에서 공기 누설이 중요한 문제임을 조명하였다. 본 연구는 개선된 덕트 접속 방식을 개발하기 위한 실험들을 소개하고, 또한 SIA 의 "S" 등급 누풍율 및 다양한 조건들을 비교하여 터널 연장에 따른 달성된 누풍율의 환기 성능을 제시한다. 본 연구의 결과로 누풍율이 <TEX>$1.46mm^2/m^2$</TEX>인 새로운 접속방식을 개발하였으며, 개선된 방식이 30 km규모의 장대터널에 적합한 것으로 분석되었다. The construction of long sub-sea tunnel does not provide the favorable condition for the installation of ventilation system to be used during construction due to the constrained construction space. For the ventilation system required during construction, the artificial island where ventilation shaft is located is constructed at some location along the sub-sea tunnel route, which requires a high construction cost. Therefore, it is intended, as much as possible technically, to minimize the construction of artificial island. However, this requires a longer distance between ventilation shafts, there-by causing increased air leakage at the ventilation duct connection points due to the higher fan pressure being required to deliver ventilation air. Previously the air leakage was studied as an important issue. In this study experiments were carried out to develop the improved duct connection method considering various conditions such as, tunnel length, etc. Additionally, its performance results with leakage rates are shown and compared to the "S" class leakage rate of SIA. As a result, the new duct coupling type of improved method is analyzed as applicable to such a 30 km long tunnel with the leakage rate of <TEX>$1.46mm^2/m^2$</TEX>, which is better performance than SIA leakage rates.

Artificial islands as a manifestation of glocalisation

The article is devoted to economic reasons for creation of artificial lands, including artificial islands, and problems related to their functioning. The scientific achievements of economic geography constitute a theoretical basis of the analysis. Economic reasons for constructing artificial islands in particular may, to a large extent, be explained by reference to a new economic geography of Paul Krugman. Therefore, the Authors associate the dynamically developing phenomenon of building artificial islands with the process of glocalisation. On the other hand, functioning of artificial islands – in their opinion – may basically be reduced to a concept of the balance of a company, as an artificial island may be treated as its counterpart.

Experimental study on the hydraulic conductivity of calcareous sand in South China Sea

ABSTRACTCharacterization of the hydraulic property of a specific geomaterial is of fundamental importance in engineering design and application. This paper reports an experimental investigation to the hydraulic conductivity of a typical marine sand, i.e., calcareous sand, which becomes increasingly popular as sea-filling material for land reclamation or construction of artificial islands. A series of permeability tests have been performed using the calcareous sand collected from Nansha islands in South China Sea. Using the home-made permeability test apparatus (so-called velocity-controlled pressure-differential acquisition flow apparatus), the relationship between flow velocity and hydraulic gradient was obtained and the hydraulic conductivity of calcareous sand was then determined accordingly. The effects of important parameters, including particle shape and particle size distribution on the hydraulic conductivity of calcareous sand, were assessed. To investigate the effect of particle size distribution on the hydraulic conductivity of calcareous sand, two often-used parameters, i.e., nonuniformity coefficient and curvature coefficient were considered in this study. To quantitatively evaluate the irregularity of soil particle, a particle-shape parameter was introduced and it was able to consider sphericity and circularity of highly irregular particle. Two materials, namely, Fujian quartz sand and glass beads consisting of particles of characteristic shape, were also used in the permeability tests, and they were used to compare with calcareous sand. Through the comparison, the effect of particle shape of calcareous sand on its hydraulic conductivity was examined based on the newly introduced particle shape parameter. The test results indicate that the particle size distribution has a significant influence on the hydraulic conductivity of calcareous sand. The quite irregular particle shape is able to reduce the hydraulic conductivity of the calcareous sand. A comparative study of hydraulic conductivity between the theoretical prediction and experimental measurement was performed, and it is concluded that an improvement of theoretical model for prediction of the hydraulic conductivity of the porous media consisting of particles with highly irregular shapes, such as the calcareous sand, is still required.