1,697 research outputs found

    Adaptation to Sea-level Rise in the People’s Republic of China – Assessing the Institutional Dimension of Alternative Organisational Frameworks

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    Global sea-levels are rising due to global warming. Major impacts on the world’s coasts are sand beach erosion, salination of ground water, and inundation. Adaptation is the only option to address these future threats as the mitigation of CO2 emissions is not capable of preventing sea-level rise. There are several organisational frameworks existing that can incorporate adaptation measures. Integrated Coastal Zone Management is proposed most often. Alternative frameworks are disaster management and sectoral frameworks involved in prevention activities, such as the water management that often holds responsibility for dike building. However, the integration of adaptation into an organisation framework is further dependent on institutional capacity within a political system. In order to illustrate what approach is feasible for a hierarchical political system the People’s Republic of China is taken as an example. An analysis of various frameworks and institutional responsibilities shows that the institutional dimension of organisation is decisive when seeking for an adequate framework to include adaptation to sea-level rise in. This paper is based on empirical results from a series of interviews and the analysis of official publications on frameworks and institutional responsibilities. It concludes with a recommendation on a climate change based framework.adaptation, sea-level rise, climate change, institutions, frameworks

    Review of geomechanical problems of accumulation and reduction of mining industry wastes, and ways of their solution

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    Purpose. The identification of geomechanical problems of mining industry wastes accumulation and substantiation of the ways for their solution with the possibility of processing the watery technogenic feedstock by fine classification with dewatering. Methods. To achieve this purpose, an integrated approach is used in this work, which includes the scientific and technical analysis of research according to wastes accumulation, state statistics data, analytical studies of the strata compaction ratio of aqueous rocks, affecting the subsidence of the earth surface. This also includes the bench experimental studies to establish the dependence of changes in moisture content and the extraction of fine classes in screened products depending on the screening time at shock-vibrating screening by a new method for separating the enrichment wastes before to stockpile them into a pond. Findings. The developed mathematical apparatus has been proposed for determining the parameters of geomechanical processes in technogenic massifs. It has been shown that in order to reduce the technogenic load and manifestation of negative geomechanical processes, it is necessary to reduce the area of land under the waste ponds and the accumulated volumes themselves of mining and enrichment wastes. The dependences have been established of the preliminary enrichment complex on the qualitative parameters of the feedstock and the technological parameters of the equipment. It has been revealed that the mineral stock, formed from wide grain-size classes with a high content of particles less than 0.2 mm, is dewatered up to 18 – 22% by traditional methods and is practically not classified. Originality. A mathematical model has been proposed of screening and dewatering kinetics, which takes into account comprehensively the initial distribution of particles and liquid throughout the height of the screened material layer, segregation, mixing, sifting, vibrational transportation features (rate, multiplicity and number of falls over the period of vibrational transportation) and change in the height of the layer. This model is different due to the account of the mutual influence of classification by coarseness and dewatering. Practical implications. The represented dependences can be used to predict the development of negative geomechanical processes. The obtained results make it possible by means of a calculation to determine rational parameters of the screen and screening process with dewatering at processing of various feedstock with the use of initial data. The use of technology, which includes a fine classification in wastes processing, will allow: increase the economic efficiency of enterprises; to expand the feedstock base for construction, coke and chemical industries and power industry; to solve the problems of creating additional containers for storing the wastes; to improve significantly the environmental situation in the mining and processing regions.Мета. Виділення геомеханічних проблем накопичення відходів гірничодобувної промисловості та обґрунтування шляхів їх вирішення з можливістю переробки обводненої техногенної сировини шляхом тонкої класифікації зі зневодненням. Методика. Для досягнення поставленої мети в роботі використано комплексний підхід, що включає науково-технічний аналіз досліджень щодо накопичення відходів, даних державної статистики, аналітичні дослідження величини ущільнення пластів водомістких порід, що впливає на просідання поверхні, а також стендові експериментальні дослідження зі встановлення залежності зміни вологості й вилучення тонких класів у продуктах грохочення залежно від його тривалості при віброударному грохоченні новим способом для розділення відходів збагачення перед їх складуванням у накопичувач. Результати. Запропоновано розроблений математичний апарат щодо визначення параметрів геомеханічних процесів у техногенних масивах. Показано, що для зменшення техногенного навантаження та проявів негативних геомеханічних процесів необхідно скоротити площу земель під накопичувачами відходів та обсяги самих накопичуваних відходів видобутку і збагачення. Встановлено залежності комплексу попереднього збагачення від якісних параметрів вихідної сировини та технологічних параметрів обладнання. Виявлено, що мінеральна сировина, сформована з широких класів крупності з великим вмістом частинок менше 0.2 мм, традиційними способами зневоднюється до 18 – 22% і практично не класифікується. Наукова новизна. Запропоновано математичну модель кінетики грохочення і зневоднення, що комплексно враховує початковий розподіл часток і рідини за висотою шару матеріалу, що грохочеться, сегрегацію, перемішування, просіювання, особливості вібротранспортування (швидкість, кратність і кількість падінь за період вібротранспортування) та зміну висоти шару, що відрізняється урахуванням взаємного впливу класифікації за крупністю й зневоднення. Практична значимість. Наведені залежності можуть бути використані для прогнозування розвитку негативних геомеханічних процесів. Застосування технології, що включає тонку класифікацію, при переробці відходів дозволить підвищити економічну ефективність підприємств; розширити сировинну базу для будівельних, коксохімічних виробництв і енергетики; вирішити проблеми створення додаткових ємностей для складування відходів; значно поліпшити екологічний стан у видобувних і переробних регіонах.Цель. Выделение геомеханических проблем накопления отходов горнодобывающей промышленности и обоснование путей их решения с возможностью переработки обводненного техногенного сырья путем тонкой классификации с обезвоживанием. Методика. Для достижения поставленной цели в работе использован комплексный подход, включающий научно-технический анализ исследований по накоплению отходов, данных государственной статистики, аналитические исследования величины уплотнения пластов водосодержащих пород, влияющей на проседание поверхности, а также стендовые экспериментальные исследования по установлению зависимости изменения влажности и извлечения тонких классов в продуктах грохочения в зависимости от его продолжительности при виброударном грохочении новым способом для разделения отходов обогащения перед их складированием в накопитель. Результаты. Предложен разработанный математический аппарат по определению параметров геомеханических процессов в техногенных массивах. Показано, что для уменьшения техногенной нагрузки и проявления негативных геомеханических процессов необходимо сократить площадь земель под накопителями отходов и объемы самих накапливаемых отходов добычи и обогащения. Установлены зависимости комплекса предобогащения от качественных параметров исходного сырья и технологических параметров оборудования. Выявлено, что минеральное сырье, сформированное из широких классов крупности с большим содержанием частиц менее 0.2 мм, традиционными способами обезвоживается до 18 – 22% и практически не классифицируется. Научная новизна. Предложена математическая модель кинетики грохочения и обезвоживания комплексно учитывающая начальные распределения частиц и жидкости по высоте слоя грохотимого материала, сегрегацию, перемешивание, просеивание, особенности вибротранспортирования (скорость, кратность и количество падений за период вибротранспортирования) и изменение высоты слоя, отличающаяся учетом взаимного влияния классификации по крупности и обезвоживания. Практическая значимость. Приведенные зависимости могут быть использованы для прогнозирования развития негативных геомеханических процессов. Применение технологии, включающей тонкую классификацию, при переработке отходов позволит повысить экономическую эффективность предприятий; расширить сырьевую базу для строительных, коксохимических производств и энергетики; решить проблемы создания дополнительных емкостей для складирования отходов; значительно улучшить экологическую обстановку в добывающих и перерабатывающих регионах.The authors express particular gratitude to the management and employees of PJSC “United Mining Chemical Company”, Vilnohirsk Mining Metallurgic Integrated Plant, branch of TSOF Pavlohradska, DTEK Pavlohradvuhilia PJSC for providing the factual materials (enrichment wastes) to conduct research under laboratory conditions

    Imaging multi-age construction settlement behaviour by advanced SAR interferometry

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    This paper focuses on the application of Advanced Satellite Synthetic Aperture Radar Interferometry (A-DInSAR) to subsidence-related issues, with particular reference to ground settlements due to external loads. Beyond the stratigraphic setting and the geotechnical properties of the subsoil, other relevant boundary conditions strongly influence the reliability of remotely sensed data for quantitative analyses and risk mitigation purposes. Because most of the Persistent Scatterer Interferometry (PSI) measurement points (Persistent Scatterers, PSs) lie on structures and infrastructures, the foundation type and the age of a construction are key factors for a proper interpretation of the time series of ground displacements. To exemplify a methodological approach to evaluate these issues, this paper refers to an analysis carried out in the coastal/deltaic plain west of Rome (Rome and Fiumicino municipalities) affected by subsidence and related damages to structures. This region is characterized by a complex geological setting (alternation of recent deposits with low and high compressibilities) and has been subjected to different urbanisation phases starting in the late 1800s, with a strong acceleration in the last few decades. The results of A-DInSAR analyses conducted from 1992 to 2015 have been interpreted in light of high-resolution geological/geotechnical models, the age of the construction, and the types of foundations of the buildings on which the PSs are located. Collection, interpretation, and processing of geo-thematic data were fundamental to obtain high-resolution models; change detection analyses of the land cover allowed us to classify structures/infrastructures in terms of the construction period. Additional information was collected to define the types of foundations, i.e., shallow versus deep foundations. As a result, we found that only by filtering and partitioning the A-DInSAR datasets on the basis of the above-mentioned boundary conditions can the related time series be considered a proxy of the consolidation process governing the subsidence related to external loads as confirmed by a comparison with results from a physically based back analysis based on Terzaghi's theory. Therefore, if properly managed, the A-DInSAR data represents a powerful tool for capturing the evolutionary stage of the process for a single building and has potential for forecasting the behaviour of the terrain-foundation-structure combination

    Advances in Remote Sensing-based Disaster Monitoring and Assessment

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    Remote sensing data and techniques have been widely used for disaster monitoring and assessment. In particular, recent advances in sensor technologies and artificial intelligence-based modeling are very promising for disaster monitoring and readying responses aimed at reducing the damage caused by disasters. This book contains eleven scientific papers that have studied novel approaches applied to a range of natural disasters such as forest fire, urban land subsidence, flood, and tropical cyclones

    Geomechanics of subsurface water withdrawal and injection

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    Land subsidence and uplift, ground ruptures, and induced seismicity are the principal geomechanic effects of groundwater withdrawal and injection. The major environmental consequence of groundwater pumping is anthropogenic land subsidence. The first observation concerning land settlement linked to subsurface processes was made in 1926 by the American geologists Pratt and Johnson, who wrote that \u2018\u2018the cause of subsidence is to be found in the extensive extraction of fluid from beneath the affected area.\u2019\u2019 Since then, impressive progress has been made in terms of: (a) recognizing the basic hydrologic and geomechanic principles underlying the occurrence; (b) measuring aquifer compaction and ground displacements, both vertical and horizontal; (c) modeling and predicting the past and future event; and (d) mitigating environmental impact through aquifer recharge and/or surface water injection. The first milestone in the theory of pumped aquifer consolidation was reached in 1923 by Terzaghi, who introduced the principle of \u2018\u2018effective intergranular stress.\u2019\u2019 In the early 1970s, the emerging computer technology facilitated development of the first mathematical model of the subsidence of Venice, made by Gambolati and Freeze. Since then, the comprehension, measuring, and simulation of the occurrence have improved dramatically. More challenging today are the issues of ground ruptures and induced/triggered seismicity, which call for a shift from the classical continuum approach to discontinuous mechanics. Although well known for decades, anthropogenic land subsidence is still threatening large urban centers and deltaic areas worldwide, such as Bangkok, Jakarta, and Mexico City, at rates in the order of 10 cm/yr

    PREGLED HAZARDA PROUZROČENOGA SLIJEGANJEM POVRŠINE U DELTI PEKALONGAN, SREDIŠNJA JAVA: UVID IZ PODZEMLJA

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    Land subsidence is a global threat to coastal areas worldwide, including the North Java coastal area. Of many areas experiencing land subsidence in North Java, the rate of land subsidence in Pekalongan has matched the high subsidence rates usually found in big cities. The rate of land subsidence in Pekalongan far exceeds the sea-level rise, resulting in a looming threat of land loss. The devastating impacts of land subsidence are the manifestation of its subsurface movement. Therefore, it is essential to understand the subsurface to elucidate the mechanism of land subsidence. Previous studies on land subsidence in Pekalongan are mainly related to subsidence rate monitoring and have not elaborated on the subsurface condition. This paper reviews the Pekalongan subsurface geology based on available literature to provide insight into the land subsidence problem. The results revealed that the land subsidence occurs in the recent alluvial plain of Pekalongan, consisting of a 30-70 m thick compressible deposit. Possible mechanisms of land subsidence arise from natural compaction, over-exploitation of confined groundwater, and increased built areas. As the seismicity of the study area is low, tectonic influence on land subsidence is considered negligible. It is expected that the offshore, nearshore, and swamp deposits are still naturally compacting. As the surface water supply is minimal, over-exploitation of groundwater resources from the deltaic and Damar Formation aquifers occurs. In the end, future research direction is proposed to reduce the impacts of the subsidence hazard.Slijeganje površine tla prijetnja je svim obalnim područjima, pa tako i obali sjeverne Jave. Niz područja u tome prostoru podložno je takvu slijeganju. Iznos toga spuštanja posebno je izražen u velikim gradovima područja Pekalongan. Taj iznos daleko nadilazi porast morske razine rezultirajući gubitkom kopna. Vrlo velik učinak takvih površinskih spuštanja odražava se također i u dubini. Zato je nužno razumjeti ispodpovršinske pojave kako bi se objasnilo samo spuštanje površine. Prethodna istraživanja tih pojava u Pekalonganu uglavnom su bila usmjerena na praćenje iznosa spuštanja, bez uvida u dubinske odnose. Ovdje je prikazana dubinska geologija istraživanoga područja, pregledom dostupne literature. Rezultati su pokazali kako se spuštanje događa u recentnoj aluvijalnoj ravnici Pekalongana, koja obuhvaća tlo debljine 30 – 70 m. Jedan od mogućih uzroka spuštanja jest prirodno zbijanje, zatim pretjerana eksploatacija podzemnih voda te prevelika izgrađenost. Seizmičnost je prostora mala, stoga je i utjecaj tektonike na taj proces zanemariv. Nadalje, morski, priobalni i močvarni talozi podložni su recentnom, prirodnom zbijanju. Kako je pritok svježe, meteorske vode minimalan, dolazi do pretjerane eksploatacije vodonosnika formacije Damar u delti. Predložena su buduća tematska istraživanja kojima bi se smanjio utjecaj opasnosti proizišlih iz slijeganja

    CLIVAR Exchanges No. 36. PAGES-CLIVAR Intersection: Climate Forcings

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    Study on Ground Deformation During Shield Tunnel Construction

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    Through the systematic analysis of the ground settlement generatedby the process of shield tunneling, the relationships between grounddeformation and construction parameters are studied in this paper. Basedon the assumption of linear small deformation, a mathematical model ofthe relationship between ground deformation and construction parametersis set up. The principle and method of optimization for estimating grounddeformation is studied. The actual measured data are compared with theresults of theoretical analysis in a case. Considering different groundformations in different construction sites with different adverse effectson surface and underground structures, the ground surface deformationscaused by shield tunneling is an aimed topic in this paper. The contributionsand research implications are the revealed relationships between the grounddeformation and the shield tunneling parameters during construction
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