Most soft clays in their natural state exhibit a small degree of overconsolidation resulting from changes in ground water level, delayed consolidation, or other causes. The overconsolidation ratio is commonly in the range of 1.0 to 2.5. Under surface loading pore pressures in such a deposit will develop as for an elastic material until the effective stresses reach a yield condition or failure condition. In the latter case the soil can continue to carry additional total stresses within confined zones and pore pressures in these zones will continue to increase. In the former case the soil will continue to deform plastically until it reaches failure, showing, in general, different pore pressure responses in these two phases. Thus pore pressure response at any point in a soft clay deposit under increasing surface loading may show two or three distinct phases, although in some cases the plastic and failure responses may be almost indistinguishable. In this report evidence is presented for the yield condition from a study of published laboratory test results. Expressions are then developed for the pore pressures to be expected in the field for each of the three phases -- elastic, plastic, and contained failure -- as a function of the vertical total stress increment at any point in the soil mass. (Author).

Most soft clays in their natural state exhibit a small degree of overconsolidation resulting from changes in ground water level, delayed consolidation, or other causes. The overconsolidation ratio is commonly in the range of 1.0 to 2.5. Under surface loading, pore pressures in such a deposit will develop as for an elastic material until the effective stresses reach a yield condition or failure condition. In the latter case the soil can continue to carry additional total stresses within confined zones and pore pressures in these zones will continue to increase. In the former case the soil will continue to deform plastically until it reaches failure, showing, in general, different pore pressure responses in these two phases. Thus pore pressure response at any point in a soft clay deposit under increasing surface loading may show two or three distinct phases, although in some cases the plastic and failure responses may be almost indistinguishable. This report examines three published field records.

Geotechnical Aspects of Underground Construction in Soft Ground comprises the second Fujita lecture, three keynote lectures and the regular papers presented at the Ninth International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground (IS - Sao Paulo 2017, Sao Paulo, Brazil, 4-6 April 2017). The Symposium was organized by the Brazilian Tunnelling Committee (CBT) of the Brazilian Geotechnical Society (ABMS), under the auspices of the Technical Committee TC204 of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). The contributions cover a wide range of topics: - Deep Excavations - Interaction with Adjacent Structures - Mechanized Excavations - Sequential Excavations - Physical Modelling and Field Tests - Case Histories Geotechnical Aspects of Underground Construction in Soft Ground is particularly aimed at academics and professionals interested or involved in geotechnical and underground engineering. Similarly to previous editions, the contributions are a valuable source of reference on the current practice on the analysis, design and construction of tunnels, deep excavations and large underground structures, with particular emphasis on the development, effects and control of ground movements, their interaction with existing structures, mitigation measures and risk management. IS - Sao Paulo 2017 is the latest in a series of ISSMGE’s TC204 symposia, which began in New Delhi (1993), followed by symposia in London (1996), Tokyo (1999), Toulouse (2002), Amsterdam (2005), Shanghai (2008), Rome (2011) and Seoul (2014).

GEOTECHNICAL ASPECTS OF UNDERGROUND CONSTRUCTION IN SOFT GROUND comprises a collection of 112 contributions presented at the Tenth International Symposium on Geotechnical Aspects of Underground Construction in Soft Ground, held in Cambridge, United Kingdom, 27-29th June 2022. This 2nd edition also includes four general reports on the symposium themes which give an overview of the papers submitted to the symposium, covered in four technical sessions. The symposium is the latest in a series which began in New Delhi in 1994, and was followed by symposia in London (1996), Tokyo (1999), Toulouse (2002), Amsterdam (2005), Shanghai (2008), Rome (2011), Seoul (2014) and Sao Paulo (2017). This symposium was organised by the Geotechnical Research Group at the University of Cambridge, under the auspices of the Technical Committee TC204 of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). Geotechnical Aspects of Underground Construction in Soft Ground includes contributions from more than 25 countries on the research, design and construction of underground works in soft ground. The contributions cover the following themes: Field case studies Sensing technologies and monitoring for underground construction in soft ground Physical and numerical modelling of tunnels and deep excavations in soft ground Seismic response of underground infrastructure in soft ground Design and application of ground improvement for underground construction Ground movements, interaction with existing structures and mitigation measures Similar to previous editions, GEOTECHNICAL ASPECTS OF UNDERGROUND CONSTRUCTION IN SOFT GROUND represents a valuable source of reference on the current practice of analysis, design, and construction of tunnels and deep excavations in soft ground. The book is particularly aimed at academics and professionals interested in geotechnical and underground engineering.

"Advances in Environmental Geotechnics" presents the latest developments in this interdisciplinary field. The topics covered include basic and advanced theories for modeling of geoenvironmental phenomena, testing and monitoring for geoenvironmental engineering, municipal solid wastes and landfill engineering, sludge and dredged soils, geotechnical reuse of industrial wastes, contaminated land and remediation technology, applications of geosynthetics in geoenvironmental engineering, geoenvironmental risk assessment, management and sustainability, ecological techniques and case histories. This proceedings includes papers authored by core members of ISSMGE TC5 (International Society of Soil Mechanics and Geotechnical Engineering---Environmental Geotechnics) and geoenvironmental researchers from more than 20 countries and regions. It is a valuable reference for geoenvironmental and geotechnical engineers as well as civil engineers. Yunmin Chen, Xiaowu Tang, and Liangtong Zhan are Professors at the Department of Civil Engineering of Zhejiang University, China.

A comprehensive practical manual covering all aspects of this field, this book covers everything from the pre-design stage up to, and including, the actual use (including maintenance) of the completed structures. Much attention is given to the calculation methods available for design and construction, including establishing the soil parameters required, with emphasis placed on probabilistic safety analysis. This informative book includes an inventory of: · the properties of natural types of soil, secondary materials, and light-weight materials · raising and filling construction methods · techniques and methods to speed up consolidation and limit deformation Compiled by researchers from Fugro, Delft Geotechnics and several other Dutch contractors, it includes useful appendices focusing on particular points of interest from the preceding chapters.

This book deals with the behaviour of soft ground improved by some of the more common methods, including the installation of prefabricated vertical drains (PVDs), or the installation of soil-cement columns formed by deep mixing, or the preloading of soft ground by application of a vacuum pressure in addition to, or instead of, a surcharge loading. In particular, it describes the theories and the numerical modelling techniques that may be applied to these soft ground improvement schemes to estimate the immediate and time-dependent mechanical response of the in situ soil. Particular emphasis has been placed on methods that reliably predict ground deformations associated with ground improvement techniques. The book commences with a brief description of the various ground improvement methods and then describes general techniques for modelling the behaviour of soft clay subsoils by the finite element method, as well as details of the methods for modelling soft soils improved by the installation of PVDs. It also includes chapters describing the theory of vacuum consolidation and methods for calculating vacuum pressure-induced ground deformation, as well as a theory which can be used to predict the response of soft ground improved by the installation of soil-cement columns. An important distinguishing feature of this book is the routine use of comparisons of predictions of the proposed models with the results of laboratory studies, and particularly field case studies, in order to validate the proposed methods of analysis. The field case histories are from soft soil sites at various locations around the world. The book is directed towards students of geotechnical engineering as well as geotechnical practitioners. In the main it provides complete derivations of most of the important theoretical results, as the intention was to write a book that could be used as both a teaching text and a reference work for students and practitioners. Audience: The book is intended for geotechnical practitioners as well as for students.

This volume contains seven keynote lectures and over 100 technical contributions by scientists, researchers, engineers and students from more than 25 countries and regions worldwide on the subject of soft soil engineering.

A valuable source of reference on the current practices of analysis, design and construction of tunnels and underground structures in soft ground. This collection of reviewed papers covers a wide range of tunnelling practice, from deep excavations in Singapore to the construction of a new metro line in Barcelona. The international scope of the contributors makes this a truly comprehensive collection of work on the geotechnical aspects of soft ground excavation.