Spatial Effects in Tunnelling Through Squeezing Ground

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Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728134384
Total Pages : 173 pages
Book Rating : 4.7/5 (281 download)

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Book Synopsis Spatial Effects in Tunnelling Through Squeezing Ground by : Linard Cantieni

Download or read book Spatial Effects in Tunnelling Through Squeezing Ground written by Linard Cantieni and published by vdf Hochschulverlag AG. This book was released on 2011 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Spatial Effects in Tunneling Through Squeezing Ground

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (732 download)

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Book Synopsis Spatial Effects in Tunneling Through Squeezing Ground by : Linard Cantieni

Download or read book Spatial Effects in Tunneling Through Squeezing Ground written by Linard Cantieni and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Harmonising Rock Engineering and the Environment

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Publisher : CRC Press
ISBN 13 : 0203135253
Total Pages : 2048 pages
Book Rating : 4.2/5 (31 download)

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Book Synopsis Harmonising Rock Engineering and the Environment by : Qihu Qian

Download or read book Harmonising Rock Engineering and the Environment written by Qihu Qian and published by CRC Press. This book was released on 2011-09-14 with total page 2048 pages. Available in PDF, EPUB and Kindle. Book excerpt: Harmonising Rock Mechanics and the Environment comprises the proceedings (invited and contributed papers) of the 12th ISRM International Congress on Rock Mechanics (Beijing, China, 18-21 October 2011). The contributions cover the entire scope of rock mechanics and rock engineering, with an emphasis on the critical role of both disciplines in sustai

On the variability of squeezing behaviour in tunnelling

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

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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

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

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

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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.

Numerical Methods in Geotechnical Engineering IX

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Publisher : CRC Press
ISBN 13 : 1351003615
Total Pages : 1656 pages
Book Rating : 4.3/5 (51 download)

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Book Synopsis Numerical Methods in Geotechnical Engineering IX by : António S. Cardoso

Download or read book Numerical Methods in Geotechnical Engineering IX written by António S. Cardoso and published by CRC Press. This book was released on 2018-06-19 with total page 1656 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical Methods in Geotechnical Engineering IX contains 204 technical and scientific papers presented at the 9th European Conference on Numerical Methods in Geotechnical Engineering (NUMGE2018, Porto, Portugal, 25—27 June 2018). The papers cover a wide range of topics in the field of computational geotechnics, providing an overview of recent developments on scientific achievements, innovations and engineering applications related to or employing numerical methods. They deal with subjects from emerging research to engineering practice, and are grouped under the following themes: Constitutive modelling and numerical implementation Finite element, discrete element and other numerical methods. Coupling of diverse methods Reliability and probability analysis Large deformation – large strain analysis Artificial intelligence and neural networks Ground flow, thermal and coupled analysis Earthquake engineering, soil dynamics and soil-structure interactions Rock mechanics Application of numerical methods in the context of the Eurocodes Shallow and deep foundations Slopes and cuts Supported excavations and retaining walls Embankments and dams Tunnels and caverns (and pipelines) Ground improvement and reinforcement Offshore geotechnical engineering Propagation of vibrations Following the objectives of previous eight thematic conferences, (1986 Stuttgart, Germany; 1990 Santander, Spain; 1994 Manchester, United Kingdom; 1998 Udine, Italy; 2002 Paris, France; 2006 Graz, Austria; 2010 Trondheim, Norway; 2014 Delft, The Netherlands), Numerical Methods in Geotechnical Engineering IX updates the state-of-the-art regarding the application of numerical methods in geotechnics, both in a scientific perspective and in what concerns its application for solving practical boundary value problems. The book will be much of interest to engineers, academics and professionals involved or interested in Geotechnical Engineering.

Tunnels and Underground Cities. Engineering and Innovation Meet Archaeology, Architecture and Art

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Publisher : CRC Press
ISBN 13 : 1000175405
Total Pages : 810 pages
Book Rating : 4.0/5 (1 download)

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Book Synopsis Tunnels and Underground Cities. Engineering and Innovation Meet Archaeology, Architecture and Art by : Daniele Peila

Download or read book Tunnels and Underground Cities. Engineering and Innovation Meet Archaeology, Architecture and Art written by Daniele Peila and published by CRC Press. This book was released on 2020-06-26 with total page 810 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tunnels and Underground Cities: Engineering and Innovation meet Archaeology, Architecture and Art. Volume 7: Long and Deep Tunnels contains the contributions presented in the eponymous Technical Session during the World Tunnel Congress 2019 (Naples, Italy, 3-9 May 2019). The use of underground space is continuing to grow, due to global urbanization, public demand for efficient transportation, and energy saving, production and distribution. The growing need for space at ground level, along with its continuous value increase and the challenges of energy saving and achieving sustainable development objectives, demand greater and better use of the underground space to ensure that it supports sustainable, resilient and more liveable cities. The contributions cover a wide range of topics, from studying tunnels in squeezing ground conditions, via case studies on the Brenner Base Tunnel, the second Gotthard Tunnel, CERN (HL-LHCand the Dubai Strategic Sewerage Tunnel, to TBM steering difficulties. The book is a valuable reference text for tunnelling specialists, owners, engineers, archaeologists, architects, artists and others involved in underground planning, design and building around the world, and for academics who are interested in underground constructions and geotechnics.

Numerical Methods in Geotechnical Engineering IX, Volume 2

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Publisher : CRC Press
ISBN 13 : 0429823169
Total Pages : 724 pages
Book Rating : 4.4/5 (298 download)

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Book Synopsis Numerical Methods in Geotechnical Engineering IX, Volume 2 by : António S. Cardoso

Download or read book Numerical Methods in Geotechnical Engineering IX, Volume 2 written by António S. Cardoso and published by CRC Press. This book was released on 2018-06-27 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical Methods in Geotechnical Engineering IX contains 204 technical and scientific papers presented at the 9th European Conference on Numerical Methods in Geotechnical Engineering (NUMGE2018, Porto, Portugal, 25—27 June 2018). The papers cover a wide range of topics in the field of computational geotechnics, providing an overview of recent developments on scientific achievements, innovations and engineering applications related to or employing numerical methods. They deal with subjects from emerging research to engineering practice, and are grouped under the following themes: Constitutive modelling and numerical implementation Finite element, discrete element and other numerical methods. Coupling of diverse methods Reliability and probability analysis Large deformation – large strain analysis Artificial intelligence and neural networks Ground flow, thermal and coupled analysis Earthquake engineering, soil dynamics and soil-structure interactions Rock mechanics Application of numerical methods in the context of the Eurocodes Shallow and deep foundations Slopes and cuts Supported excavations and retaining walls Embankments and dams Tunnels and caverns (and pipelines) Ground improvement and reinforcement Offshore geotechnical engineering Propagation of vibrations Following the objectives of previous eight thematic conferences, (1986 Stuttgart, Germany; 1990 Santander, Spain; 1994 Manchester, United Kingdom; 1998 Udine, Italy; 2002 Paris, France; 2006 Graz, Austria; 2010 Trondheim, Norway; 2014 Delft, The Netherlands), Numerical Methods in Geotechnical Engineering IX updates the state-of-the-art regarding the application of numerical methods in geotechnics, both in a scientific perspective and in what concerns its application for solving practical boundary value problems. The book will be much of interest to engineers, academics and professionals involved or interested in Geotechnical Engineering. This is volume 2 of the NUMGE 2018 set.

On the Feasibility of TBM Drives in Squeezing Ground and the Risk of Shield Jamming

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Publisher : vdf Hochschulverlag AG
ISBN 13 : 3728133639
Total Pages : 202 pages
Book Rating : 4.7/5 (281 download)

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Book Synopsis On the Feasibility of TBM Drives in Squeezing Ground and the Risk of Shield Jamming by : Marco Ramoni

Download or read book On the Feasibility of TBM Drives in Squeezing Ground and the Risk of Shield Jamming written by Marco Ramoni and published by vdf Hochschulverlag AG. This book was released on 2010 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Squeezing ground represents a challenging operating environment as it may slow down or obstruct TBM operation. Due to the geometrical constraints of the equipment, relatively small convergences of 10-20 cm may lead to considerable difficulties in the machine area (sticking of the cutter head, jamming of the shield) or in the back-up area (e.g., jamming of the back-up equipment, inadmissible convergences of the bored profile, damage to the tunnel support). Depending on the number and the length of the critical stretches, squeezing conditions may even call into question the feasibility of a TBM drive. On account of this, and bearing in mind the steady increase in the number of tunnels excavated with TBMs through so-called "difficult ground conditions", the topic investigated in this PhD thesis is of great practical relevance.Based upon case histories reported in the literature, Part I sets out firstly to give an overview of the specific problems of TBM tunnelling under squeezing conditions. Part II presents a computational model which simulates accurately and efficiently the advancing TBM and the installed tunnel support in one single computational step applying the so-called "steady state method". Part III advances a number of theory-based decision aids, which will support rapid, initial assessments to be made of thrust force requirements. Part IV investigates the complex problem of the interaction between the advancing TBM, the consolidating ground and the lining. Emphasis is thereby placed on the effect of the gross advance rate and the effect of ground permeability on shield loading during regular TBM operation (the boring process including short standstills) and during a long standstill.

Experimental investigations for the modelling of anhydritic swelling claystones

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

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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

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

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

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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.

The Second Half Century of Rock Mechanics, Three Volume Set

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Publisher : CRC Press
ISBN 13 : 0415889545
Total Pages : 1356 pages
Book Rating : 4.4/5 (158 download)

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Book Synopsis The Second Half Century of Rock Mechanics, Three Volume Set by : Luis Ribeiro e Sousa

Download or read book The Second Half Century of Rock Mechanics, Three Volume Set written by Luis Ribeiro e Sousa and published by CRC Press. This book was released on 2007-08-05 with total page 1356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forty one years ago, the International Society for Rock Mechanics (ISRM) held its 1st International Congress in Lisbon, Portugal. In July 2007, the 11th ISRM Congress returned to Lisbon, where the Portuguese Geotechnical Society (SPG), the Portuguese National Group of the ISRM, hosted the meeting. The Second Half Century of Rock Mechanics comprises

Centrifuge modelling of ground improvement for double porosity clay

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

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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.

River dyke failure modeling under transient water conditions

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

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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.

Tunneling Under Squeezing Conditions

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Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (11 download)

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Book Synopsis Tunneling Under Squeezing Conditions by : Manuel De la Fuente Mata

Download or read book Tunneling Under Squeezing Conditions written by Manuel De la Fuente Mata and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the excavation of deep tunnels, squeezing ground conditions are often encountered. The squeezing behavior of the ground is characterized by large time-dependent and usually anisotropic convergences that take place at the tunnel wall. The technique of excavation has a strong influence on the tunnel response when it is excavated under squeezing conditions. This phenomenon is illustrated throughout the case study of the Fréjus road tunnel excavated with conventional drill and blast methods and of its safety gallery excavated with a single shield tunneling boring machine. They exhibit a very interesting configuration of two tunnels excavated in parallel under the same geotechnical conditions but with different excavation techniques. Monitored geotechnical data from both tunnels are analyzed and compared. Numerical simulations of both tunnels have been carried out with Flac3D. An anisotropic creep model which includes weakness planes of given orientation embedded in a visco-elasto-plastic matrix has been used for describing the behavior of the ground. A back-analysis of convergence measurements of the Fréjus road tunnel has been carried out. The behavior of the ground identified from the Fréjus road tunnel is extrapolated to predict the response of the Fréjus safety gallery in terms of the stress state in the lining. The influence of the technique of excavation on the time-dependent parameters of the ground is taken into account in the computations and its effects are discussed. It is shown that the long term ground deformation are significantly reduced with TBM excavation as compared to traditional blast and drill method.Furthermore, the convergence-confinement methods are reviewed and their applicability is discussed when they are applied to full face circular tunnels excavated in rock masses with a stiff support system near the face. In this context, a set of empirical formula are proposed which allows to accurately predict the equilibrium state between the ground and the lining in circular tunnels excavated in full section. These formula are useful in the preliminary phase of tunnel design.

Tunnel Lining Design Guide

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Publisher : Thomas Telford
ISBN 13 : 9780727729866
Total Pages : 204 pages
Book Rating : 4.7/5 (298 download)

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Book Synopsis Tunnel Lining Design Guide by : British Tunnelling Society

Download or read book Tunnel Lining Design Guide written by British Tunnelling Society and published by Thomas Telford. This book was released on 2004 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Of geotechnical and geophysical -- pr) operies 160 -- 10.3 4 Design of tunnel linings 1 61 -- 10.4 Instrumentation of the CTRL North Downs Tunnel 164 -- 10.5 References 165 -- Appendix I Abbreviations and symbols 166 -- Appendix 2 Risk management 168 -- A2l Introduction 168 -- A2.2 Scope 168 -- A23 Risk register 169 -- A21. 1 When to use the risk register 169 -- A2.32 Whalt is it? 169 -- A2.3.3 Assessment process 169 -- A2.3.4 Key steps 169 -- A2.3.5 Risk assessment, qualitative or -- quantitative? 171 -- A2.3.6 R anaingt risk 175 -- A2.4 References 17.

About the Advancing Face - Spatial Effects in Tunnel Engineering

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (97 download)

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Book Synopsis About the Advancing Face - Spatial Effects in Tunnel Engineering by : Georgios Anagnostou

Download or read book About the Advancing Face - Spatial Effects in Tunnel Engineering written by Georgios Anagnostou and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: