Instabilities in alpine permafrost: strength and stiffness in a warming regime

Download Instabilities in alpine permafrost: strength and stiffness in a warming regime PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728136409
Total Pages : 519 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis Instabilities in alpine permafrost: strength and stiffness in a warming regime by : Yuko Yamamoto

Download or read book Instabilities in alpine permafrost: strength and stiffness in a warming regime written by Yuko Yamamoto and published by vdf Hochschulverlag AG. This book was released on 2014-08-20 with total page 519 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alpine permafrost exists at high altitude at lower latitudes, such as in the Swiss Alps. Accelerating climate change, including rising mean annual air temperature and extreme rainfall conditions in alpine regions induces permafrost degradation. The warming of permafrost causes accelerated creep of rock glaciers, due to increased unfrozen water content and higher deformability of the ice phase. Recently, the development of deepening depressions has been observed in several rock glaciers in Switzerland, and the changes in land surface characteristics and drainage systems may initiate slope instabilities in rock glaciers. The main aim of this thesis is to characterise the strength and stiffness of alpine frozen soil in rock glaciers. To this end, the geotechnical response, such as creep and failure of frozen soil was investigated through a triaxial stress path testing programme with novel measurement systems for detecting acoustic emissions and measuring volumetric change. In addition, the resistance to crack initiation and propagation was investigated through a beam bending test programme on rectangular artificially frozen soil specimens, using the acoustic emission measurement system. The evaluation of laboratory tests on artificially frozen soil specimens implied that the development of deep depressions in rock glaciers occurs through differential creep and thermal degradation, and that the rate of deformation has the potential to lead to instabilities in rock glaciers. A comparison of the simulation results with the experimental data demonstrated that the semi-coupled model was successful in simulating the most important aspects of the temperature-dependent stress-strain relationship for the frozen soil behaviour that was measured at the element scale. This thesis contributes to an understanding of the variations in geotechnical response of alpine permafrost, by investigating the behaviour of artificially frozen soil specimens experimentally and numerically with time and temperature under specific stress paths. However, further investigations are necessary to assess the long-term stability of rock glaciers affected by climate change.

Instabilities in Alpine Permafrost

Download Instabilities in Alpine Permafrost PDF Online Free

Author :
Publisher :
ISBN 13 : 9783728136411
Total Pages : 0 pages
Book Rating : 4.1/5 (364 download)

DOWNLOAD NOW!


Book Synopsis Instabilities in Alpine Permafrost by : Yuko Yamamoto

Download or read book Instabilities in Alpine Permafrost written by Yuko Yamamoto and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alpine permafrost exists at high altitude at lower latitudes, such as in the Swiss Alps. Accelerating climate change, including rising mean annual air temperature and extreme rainfall conditions in alpine regions induces permafrost degradation. The warming of permafrost causes accelerated creep of rock glaciers, due to increased unfrozen water content and higher deformability of the ice phase. Recently, the development of deepening depressions has been observed in several rock glaciers in Switzerland, and the changes in land surface characteristics and drainage systems may initiate slope instabilities in rock glaciers. The main aim of this thesis is to characterise the strength and stiffness of alpine frozen soil in rock glaciers. To this end, the geotechnical response, such as creep and failure of frozen soil was investigated through a triaxial stress path testing programme with novel measurement systems for detecting acoustic emissions and measuring volumetric change. In addition, the resistance to crack initiation and propagation was investigated through a beam bending test programme on rectangular artificially frozen soil specimens, using the acoustic emission measurement system.

Geotechnical Research for Land Protection and Development

Download Geotechnical Research for Land Protection and Development PDF Online Free

Author :
Publisher : Springer
ISBN 13 : 3030213595
Total Pages : 802 pages
Book Rating : 4.0/5 (32 download)

DOWNLOAD NOW!


Book Synopsis Geotechnical Research for Land Protection and Development by : Francesco Calvetti

Download or read book Geotechnical Research for Land Protection and Development written by Francesco Calvetti and published by Springer. This book was released on 2019-06-22 with total page 802 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume gathers the latest advances, innovations, and applications in the field of geotechnical engineering, as presented by leading researchers and engineers at the 7th Italian National Congress of Geotechnical Researchers (CNRIG 2019), entitled “Geotechnical Research for the Protection and Development of the Territory” (Lecco, Italy, July 3-5, 2019). The congress is intended to promote exchanges on the role of geotechnical research and its findings regarding the protection against natural hazards, design criteria for structures and infrastructures, and the definition of sustainable development strategies. The contributions cover a diverse range of topics, including infrastructural challenges, underground space utilization, and sustainable construction in problematic soils and situations, as well as geo-environmental aspects such as landfills, environmental and energy geotechnics, geotechnical monitoring, and risk assessment and mitigation. Selected by means of a rigorous peer-review process, they will spur novel research directions and foster future multidisciplinary collaborations.

Snow and Ice-Related Hazards, Risks, and Disasters

Download Snow and Ice-Related Hazards, Risks, and Disasters PDF Online Free

Author :
Publisher : Academic Press
ISBN 13 : 0123964733
Total Pages : 812 pages
Book Rating : 4.1/5 (239 download)

DOWNLOAD NOW!


Book Synopsis Snow and Ice-Related Hazards, Risks, and Disasters by : Wilfried Haeberli

Download or read book Snow and Ice-Related Hazards, Risks, and Disasters written by Wilfried Haeberli and published by Academic Press. This book was released on 2014-10-27 with total page 812 pages. Available in PDF, EPUB and Kindle. Book excerpt: Snow and Ice-Related Hazards, Risks, and Disasters provides you with the latest scientific developments in glacier surges and melting, ice shelf collapses, paleo-climate reconstruction, sea level rise, climate change implications, causality, impacts, preparedness, and mitigation. It takes a geo-scientific approach to the topic while also covering current thinking about directly related social scientific issues that can adversely affect ecosystems and global economies. Puts the contributions from expert oceanographers, geologists, geophysicists, environmental scientists, and climatologists selected by a world-renowned editorial board in your hands Presents the latest research on causality, glacial surges, ice-shelf collapses, sea level rise, climate change implications, and more Numerous tables, maps, diagrams, illustrations and photographs of hazardous processes will be included Features new insights into the implications of climate change on increased melting, collapsing, flooding, methane emissions, and sea level rise

Snow and Ice-Related Hazards, Risks, and Disasters

Download Snow and Ice-Related Hazards, Risks, and Disasters PDF Online Free

Author :
Publisher : Elsevier
ISBN 13 : 0128171308
Total Pages : 786 pages
Book Rating : 4.1/5 (281 download)

DOWNLOAD NOW!


Book Synopsis Snow and Ice-Related Hazards, Risks, and Disasters by : Wilfried Haeberli

Download or read book Snow and Ice-Related Hazards, Risks, and Disasters written by Wilfried Haeberli and published by Elsevier. This book was released on 2021-02-12 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: Snow and Ice-Related Hazards, Risks, and Disasters, Second Edition, provides you with the latest scientific developments in sea level rise, permafrost degradation, rock/ice avalanches, glacier surges, glacial lake outburst floods, ice shelf collapses, climate change implications, causality, impacts, preparedness and mitigation. The book takes a geo-scientific approach to the topic while also covering current thinking about directly related social scientific issues that can affect ecosystems and global economies. Special emphasis is placed on the rapidly progressing effects from global warming on the cryosphere, perspectives for the future and latest scientific advances, and technological developments. Presents the latest research on causality, glacial surges, ice-shelf collapses, sea level rise, climate change implications, and more Contains numerous tables, maps, diagrams, illustrations and photographs of hazardous processes Features new insights on the implications of climate change, including increased melting, collapsing, flooding, methane emissions, and sea level rise

On the variability of squeezing behaviour in tunnelling

Download On the variability of squeezing behaviour in tunnelling PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728140058
Total Pages : 358 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis On the variability of squeezing behaviour in tunnelling by : Florence Mezger

Download or read book On the variability of squeezing behaviour in tunnelling written by Florence Mezger and published by vdf Hochschulverlag AG. This book was released on 2020-07-01 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: On the variability of squeezing behaviour in tunnelling

Experimental investigations for the modelling of anhydritic swelling claystones

Download Experimental investigations for the modelling of anhydritic swelling claystones PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728140112
Total Pages : 344 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis Experimental investigations for the modelling of anhydritic swelling claystones by : Tara Wanninger (-Huber)

Download or read book Experimental investigations for the modelling of anhydritic swelling claystones written by Tara Wanninger (-Huber) and published by vdf Hochschulverlag AG. This book was released on 2020-07-01 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental investigations for the modelling of anhydritic swelling claystones

River dyke failure modeling under transient water conditions

Download River dyke failure modeling under transient water conditions PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728136301
Total Pages : 436 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis River dyke failure modeling under transient water conditions by : Wilmer Ferney Morales Peñuela

Download or read book River dyke failure modeling under transient water conditions written by Wilmer Ferney Morales Peñuela and published by vdf Hochschulverlag AG. This book was released on 2015-11-26 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge of the performance of river dykes during flooding is necessary when designing governmental assistance plans aimed to reduce both casualties and material damage. This is especially relevant when floods have increased in their frequency during the last decades, together with the resulting material damage and life costs. Most of previous attempts for analyzing dyke breaching during flooding have neglected to consider the soil mechanics component and the influence of infiltration and saturation changes on the failure mechanisms developed in the river dyke. This research project aimed to fill that gap in knowledge by analyzing, in a comprehensive manner, the effect of transient water conditions, represented by successive flood cycles, on the seepage conditions and subsequent breaching of dykes. Therefore, three key sub-projects were carried out: • the analysis of the results from an overflow field test, • the physical modeling of small-scaled models under an enhanced gravity field, • the numerical modeling of the flow response and the resulting stability of both the air- and water-side slopes. The results from the numerical simulations matched accurately with the results obtained with the centrifuge modeling, including the prediction of local instabilities during the flood cycles for those dykes that did not include a toe filter.

On the role of constitutive behaviour in the response of squeezing ground to tunnelling

Download On the role of constitutive behaviour in the response of squeezing ground to tunnelling PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728138606
Total Pages : 205 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis On the role of constitutive behaviour in the response of squeezing ground to tunnelling by : Weijie Dong

Download or read book On the role of constitutive behaviour in the response of squeezing ground to tunnelling written by Weijie Dong and published by vdf Hochschulverlag AG. This book was released on 2017-08-14 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: Squeezing conditions in tunnelling are characterized by the occurrence of large deformations of the opening or high rock pressure that may overstress the lining. Squeezing is associated with poor quality rock. Tunnelling in squeezing ground involves great uncertainties. It is therefore very important to gain a better understanding of the underlying mechanisms. Triaxial testing is the main source of information in order to understand the mechanical features of squeezing ground. Despite the complexity of the squeezing mechanism and the behaviour observed under relatively simple loading conditions, most of previous research work and engineering design practice considers the ground as a linearly elastic, perfectly plastic material obeying the Mohr-Coulomb yield criterion. While the MC model is capable of predicting the final strength and post-failure volumetric behaviour of the squeezing rock, it cannot map some potentially important pre-failure features or the occasionally observed contractant plastic deformation. In addition, the MC model usually leads to an overestimation of the strength under undrained conditions, which is unsafe for tunnel design. The present thesis mainly addresses the influence of constitutive modelling on predictions about the response of squeezing ground to tunnelling in order to provide some general guidelines for basic engineering analysis. This objective is achieved by investigating the behaviour of squeezing rocks theoretically and experimentally, using samples from several tunnel projects, including the Gotthard base tunnel and the planned Gibraltar strait tunnel.

Centrifuge modelling of ground improvement for double porosity clay

Download Centrifuge modelling of ground improvement for double porosity clay PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728136514
Total Pages : 270 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis Centrifuge modelling of ground improvement for double porosity clay by : Emma Jane Pooley

Download or read book Centrifuge modelling of ground improvement for double porosity clay written by Emma Jane Pooley and published by vdf Hochschulverlag AG. This book was released on 2015-11-10 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Double porosity soil is characterised by a soil continuum containing two distinct porosities. Typically, this consists of macro-grains (lumps) of soil that have an internal porosity defined as the intragranular porosity. The spaces between lumps are identified as intergranular voids that give rise to the intergranular porosity. Human activities such as land reclamation or mining can give rise to large areas of land with subsoil that exhibits double porosity. The need to build in, or on, these areas is increasing, due to demand for land for industrial usage, infrastructure, and residence. However, the engineering properties of such soils are challenging, and often difficult to predict due to their inhomogeneity and a lack of information about the initial or current parameters. Double porosity mining waste landfills in Northern Bohemia in the Czech Republic were studied in this project. There, decades of open-cast mining of brown coal have left vast areas of land affected by the waste overburden that has been removed and dumped in old mining pits. Redevelopment of areas affected by mining sometimes requires construction on old overburden waste spoil heaps, which consist primarily of lumps of overconsolidated clay and are therefore characterised by a double porosity soil structure. The loading response on these clayfills entails large absolute and relative deformations, which means that ground improvement is normally needed before construction begins, to ensure that both stability and service limit state requirements are met. The primary aim of this research was a comparison, through physical modelling, of ground improvement techniques on double porosity clay landfills. A secondary objective was to contribute to the understanding of the material behaviour governing response to loading and other processes on double porosity soil.

Static effects and aspects of feasibility and design of drainages in tunnelling

Download Static effects and aspects of feasibility and design of drainages in tunnelling PDF Online Free

Author :
Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728138193
Total Pages : 228 pages
Book Rating : 4.7/5 (281 download)

DOWNLOAD NOW!


Book Synopsis Static effects and aspects of feasibility and design of drainages in tunnelling by : Sara Zingg

Download or read book Static effects and aspects of feasibility and design of drainages in tunnelling written by Sara Zingg and published by vdf Hochschulverlag AG. This book was released on 2017-02-21 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: This PhD thesis investigates the effectiveness of drainage measures with respect to two particularly important problems associated with tunnelling through water-bearing, weak ground: the stability of the tunnel face and the stability and deformation of grouting bodies. Water is an adverse factor with respect to the stability and deformation of underground structures due to the pore water pressure and the seepage forces associated with seepage flow towards the tunnel. Drainage boreholes reduce the pore water pressure and the seepage forces in the vicinity of the cavity. Furthermore, loss of pore water pressure increases the effective stresses and thus the shearing resistance of the ground („consolidation“), which is favourable in terms the deformation occurring during and after tunnelling. The goal of the PhD thesis is to elaborate a more detailed understanding of the interrelationships between drainage measures and the stability of the tunnel face and grouting bodies. The main objectives of the investigations relating to the tunnel face are: 1. analysis of face stability through limit equilibrium computations taking account of the numerically determined seepage flow conditions prevailing in the ground after the implementation of drainage measures; 2. systematic investigation of tunnel face stability considering several different drainage layouts and working out designnomograms; 3. consideration of a series of aspects limiting pore pressure relief and thus the effectiveness of drainage measures and their impact on face stability. The main objectives of the investigations with regard to grouting bodies are: 1. a study of the stabilizing effect of the virtual case of ideal drainage on tunnel support and plastification in grouted fault zones in plane strain conditions; 2. a comparison with the stabilizing effect of real drainage layouts, i.e. when considering pore pressure relief due to specific drainage borehole arrangements; 3. application of the drainage measure both before and after the injection works. In summary, the contribution of this PhD thesis is the detailed investigation of the static effects of drainage measures during tunnelling in water-bearing ground with respect to the stability of the tunnel face and the grouting body as well as the supply of design aids capable of providing a quick assessment of face stability when considering a number of advance drainage schemes.

Influences of Snow Supporting Structures on the Thermal Regime of the Ground in Alpine Permafrost Terrain

Download Influences of Snow Supporting Structures on the Thermal Regime of the Ground in Alpine Permafrost Terrain PDF Online Free

Author :
Publisher :
ISBN 13 :
Total Pages : 162 pages
Book Rating : 4.:/5 (7 download)

DOWNLOAD NOW!


Book Synopsis Influences of Snow Supporting Structures on the Thermal Regime of the Ground in Alpine Permafrost Terrain by : Marcia Phillips

Download or read book Influences of Snow Supporting Structures on the Thermal Regime of the Ground in Alpine Permafrost Terrain written by Marcia Phillips and published by . This book was released on 2000 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thèse. Lettres. 2000

Permafrost Soils

Download Permafrost Soils PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 3540693718
Total Pages : 346 pages
Book Rating : 4.5/5 (46 download)

DOWNLOAD NOW!


Book Synopsis Permafrost Soils by : Rosa Margesin

Download or read book Permafrost Soils written by Rosa Margesin and published by Springer Science & Business Media. This book was released on 2008-10-31 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most of the Earth’s biosphere is characterized by low temperatures. Vast areas (>20%) of the soil ecosystem are permanently frozen or are unfrozen for only a few weeks in summer. Permafrost regions occur at high latitudes and also at high ele- tions; a significant part of the global permafrost area is represented by mountains. Permafrost soils are of global interest, since a significant increase in temperature is predicted for polar regions. Global warming will have a great impact on these soils, especially in northern regions, since they contain large amounts of organic carbon and act as carbon sinks, and a temperature increase will result in a release of carbon into the atmosphere. Additionally, the intensified release of the clima- relevant tracer gas methane represents a potential environmental harzard. Significant numbers of viable microorganisms, including bacteria, archaea, p- totrophic cyanobacteria and green algae, fungi and protozoa, are present in per- frost, and the characteristics of these microorganisms reflect the unique and extreme conditions of the permafrost environment. Remarkably, these microorg- isms have been reported to be metabolically active at subzero temperatures, even down to ?20°C.

Global Change and Mountain Regions

Download Global Change and Mountain Regions PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 140203508X
Total Pages : 642 pages
Book Rating : 4.4/5 (2 download)

DOWNLOAD NOW!


Book Synopsis Global Change and Mountain Regions by : Uli M. Huber

Download or read book Global Change and Mountain Regions written by Uli M. Huber and published by Springer Science & Business Media. This book was released on 2006-03-09 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives an overview of the state of research in fields pertaining to the detection, understanding and prediction of global change impacts in mountain regions. More than sixty contributions from paleoclimatology, cryospheric research, hydrology, ecology, and development studies are compiled in this volume, each with an outlook on future research directions. The book will interest meteorologists, geologists, botanists and climatologists.

Abrupt Climate Change

Download Abrupt Climate Change PDF Online Free

Author :
Publisher : National Academies Press
ISBN 13 : 0309133041
Total Pages : 252 pages
Book Rating : 4.3/5 (91 download)

DOWNLOAD NOW!


Book Synopsis Abrupt Climate Change by : National Research Council

Download or read book Abrupt Climate Change written by National Research Council and published by National Academies Press. This book was released on 2002-04-23 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: The climate record for the past 100,000 years clearly indicates that the climate system has undergone periodic-and often extreme-shifts, sometimes in as little as a decade or less. The causes of abrupt climate changes have not been clearly established, but the triggering of events is likely to be the result of multiple natural processes. Abrupt climate changes of the magnitude seen in the past would have far-reaching implications for human society and ecosystems, including major impacts on energy consumption and water supply demands. Could such a change happen again? Are human activities exacerbating the likelihood of abrupt climate change? What are the potential societal consequences of such a change? Abrupt Climate Change: Inevitable Surprises looks at the current scientific evidence and theoretical understanding to describe what is currently known about abrupt climate change, including patterns and magnitudes, mechanisms, and probability of occurrence. It identifies critical knowledge gaps concerning the potential for future abrupt changes, including those aspects of change most important to society and economies, and outlines a research strategy to close those gaps. Based on the best and most current research available, this book surveys the history of climate change and makes a series of specific recommendations for the future.

Climate Change: An Integrated Perspective

Download Climate Change: An Integrated Perspective PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 0306479826
Total Pages : 425 pages
Book Rating : 4.3/5 (64 download)

DOWNLOAD NOW!


Book Synopsis Climate Change: An Integrated Perspective by : Pim Martens

Download or read book Climate Change: An Integrated Perspective written by Pim Martens and published by Springer Science & Business Media. This book was released on 2006-04-11 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Global climate change - rapid, substantial and human induced - may have radical consequences for life on earth. The problem is a complex one, however, demanding a multi-disciplinary approach. A simple cost-benefit analysis cannot capture the essentials, nor can the issue be reduced to an emissions reduction game, as the Kyoto process tries to do. It is much more sensible to adopt an integrative approach, which reveals that global climate change needs to be considered as a spider in a web, a triggering factor for a range of other, related problems - land use changes, water supply and demand, food supply, energy supply, human health, air pollution, etc. But an approach like this, which takes account of all items of knowledge, known and uncertain, does not produce clear-cut, final and popular answers. It does provide useful insights, however, which will allow comprehensive and effective long-term climate strategies to be put into effect. Climate Change: An Integrated Perspective will appeal to a broad spectrum of readers. It is a useful source for the climate-change professionals, such as policy makers and analysts, natural and social scientists. It is also suitable for educationalists, students and indeed anyone interested in the fascinating world of multidisciplinary research underlying our approach to this global change issue.

Global Outlook for Ice & Snow

Download Global Outlook for Ice & Snow PDF Online Free

Author :
Publisher : UNEP/Earthprint
ISBN 13 : 9789280727999
Total Pages : 240 pages
Book Rating : 4.7/5 (279 download)

DOWNLOAD NOW!


Book Synopsis Global Outlook for Ice & Snow by : Pål Prestrud

Download or read book Global Outlook for Ice & Snow written by Pål Prestrud and published by UNEP/Earthprint. This book was released on 2007 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by more than 70 scientists from around the world, this publication assesses the state of the environment and the trends in ice and snow-covered regions (the cryosphere). It looks at the significance of climate changes for ecosystems and human well-being, both now and in the years to come, given that changes in ice and snow alter the distribution of the earth's heat and water, and influence regional and global ocean circulation. This publication is an official project of the International Polar Year 2007-2008.