Artificial Ground Freezing in Clayey Soils
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Stability and Water Leakage of Hard Rock Subsea Tunnels
Stability and water leakage of hard rock subsea tunnels B. Nilsen The Norwegian University of Science and Technology, Trondheim, Norway A. Palmstrøm Norconsult as, Sandvika, Norway ABSTRACT: The many undersea tunnels along the coast of Norway offer excellent opportunities to study the key factors determining stability and water leakage in hard rock subsea tunnels. About 30 such tunnels have been constructed in Norway the last 20 years, all of them excavated by drill and blast. The longest tunnel is 7.9 km with its deepest point 260 metres below sea level. Although all tunnels are located in Precambrian or Palaeozoic rocks, some of them have encountered complex faulting or less competent rocks like shale and schist. The severe tunnelling problems met in these tunnels emphasise the need of a better understanding of the key factors determining stability and water leakage of such projects. This has been discussed based on the experience from several completed projects. 1 INTRODUCTION 2 CHARACTERISTICS OF SUBSEA TUNNELS In Norway, about 30 subsea tunnels, comprising Compared to conventional tunnels, subsea tunnels more than 100 km have been built the last 20 years. are quite special in several ways. Concerning Most of these are 2 or 3 lane road tunnels, but some engineering geology and rock engineering, the are also for water, sewage, or oil and gas pipelines. following factors are the most important (see also All tunnels so far are drill and blast. The locations of Figure 4): some key projects, and tunnels being discussed later • Most of the project area is covered by water. in this paper, are shown in Figure 1, and some main Hence, special investigation techniques need to figures concerning length and depth are given in be applied, and interpretation of the investigation Table 1. -
SECTION 3 Erosion Control Measures
SECTION 3 Erosion Control Measures 1. SEEDING When • Bare soil is exposed to erosive forces from wind and or water. Why • A cost effective way to prevent erosion by protecting the soil from raindrop impact, flowing water and wind. • Vegetation binds soil particles together with a dense root system, increasing infiltration thereby reducing runoff volume and velocity. Where • On all disturbed areas except where non-vegetative stabilization measures are being used or where seeding would interfere with agricultural activity. Scheduling • During the recommended temporary and permanent seeding dates outlined below. • Dormant seeding is acceptable. How 1. Site Assessment. Determine site physical characteristics including available sunlight, slope, adjacent topography, local climate, proximity to sensitive areas or natural plant communities, and soil characteristics such as natural drainage class, texture, fertility and pH. 2. Seed Selection. Use seed with acceptable purity and germination tests that are viable for the planned seeding date. Seed that has become wet, moldy or otherwise damaged is unacceptable. Select seed depending on, location and intended purpose. A mixture of native species for permanent cover may provide some advantages because they have coevolved with native wildlife and other plants and typically play an important function in the ecosystem. They are also adapted to the local climate and soil if properly selected for site conditions; can dramatically reduce fertilizer, lime and maintenance requirements; and provide a deeper root structure. When re- vegetating natural areas, introduced species may spread into adjacent natural areas, native species should be used. Noxious or aquatic nuisance species shall not be used (see list below). If seeding is a temporary soil erosion control measure select annual, non-aggressive species such as annual rye, wheat, or oats. -
Ice Ic” Werner F
Extent and relevance of stacking disorder in “ice Ic” Werner F. Kuhsa,1, Christian Sippela,b, Andrzej Falentya, and Thomas C. Hansenb aGeoZentrumGöttingen Abteilung Kristallographie (GZG Abt. Kristallographie), Universität Göttingen, 37077 Göttingen, Germany; and bInstitut Laue-Langevin, 38000 Grenoble, France Edited by Russell J. Hemley, Carnegie Institution of Washington, Washington, DC, and approved November 15, 2012 (received for review June 16, 2012) “ ” “ ” A solid water phase commonly known as cubic ice or ice Ic is perfectly cubic ice Ic, as manifested in the diffraction pattern, in frequently encountered in various transitions between the solid, terms of stacking faults. Other authors took up the idea and liquid, and gaseous phases of the water substance. It may form, attempted to quantify the stacking disorder (7, 8). The most e.g., by water freezing or vapor deposition in the Earth’s atmo- general approach to stacking disorder so far has been proposed by sphere or in extraterrestrial environments, and plays a central role Hansen et al. (9, 10), who defined hexagonal (H) and cubic in various cryopreservation techniques; its formation is observed stacking (K) and considered interactions beyond next-nearest over a wide temperature range from about 120 K up to the melt- H-orK sequences. We shall discuss which interaction range ing point of ice. There was multiple and compelling evidence in the needs to be considered for a proper description of the various past that this phase is not truly cubic but composed of disordered forms of “ice Ic” encountered. cubic and hexagonal stacking sequences. The complexity of the König identified what he called cubic ice 70 y ago (11) by stacking disorder, however, appears to have been largely over- condensing water vapor to a cold support in the electron mi- looked in most of the literature. -
A Primer on Ice
A Primer on Ice L. Ridgway Scott University of Chicago Release 0.3 DO NOT DISTRIBUTE February 22, 2012 Contents 1 Introduction to ice 1 1.1 Lattices in R3 ....................................... 2 1.2 Crystals in R3 ....................................... 3 1.3 Comparingcrystals ............................... ..... 4 1.3.1 Quotientgraph ................................. 4 1.3.2 Radialdistributionfunction . ....... 5 1.3.3 Localgraphstructure. .... 6 2 Ice I structures 9 2.1 IceIh........................................... 9 2.2 IceIc........................................... 12 2.3 SecondviewoftheIccrystalstructure . .......... 14 2.4 AlternatingIh/Iclayeredstructures . ........... 16 3 Ice II structure 17 Draft: February 22, 2012, do not distribute i CONTENTS CONTENTS Draft: February 22, 2012, do not distribute ii Chapter 1 Introduction to ice Water forms many different crystal structures in its solid form. These provide insight into the potential structures of ice even in its liquid phase, and they can be used to calibrate pair potentials used for simulation of water [9, 14, 15]. In crowded biological environments, water may behave more like ice that bulk water. The different ice structures have different dielectric properties [16]. There are many crystal structures of ice that are topologically tetrahedral [1], that is, each water molecule makes four hydrogen bonds with other water molecules, even though the basic structure of water is trigonal [3]. Two of these crystal structures (Ih and Ic) are based on the same exact local tetrahedral structure, as shown in Figure 1.1. Thus a subtle understanding of structure is required to differentiate them. We refer to the tetrahedral structure depicted in Figure 1.1 as an exact tetrahedral structure. In this case, one water molecule is in the center of a square cube (of side length two), and it is hydrogen bonded to four water molecules at four corners of the cube. -
Arxiv:2004.08465V2 [Cond-Mat.Stat-Mech] 11 May 2020
Phase equilibrium of liquid water and hexagonal ice from enhanced sampling molecular dynamics simulations Pablo M. Piaggi1 and Roberto Car2 1)Department of Chemistry, Princeton University, Princeton, NJ 08544, USA a) 2)Department of Chemistry and Department of Physics, Princeton University, Princeton, NJ 08544, USA (Dated: 13 May 2020) We study the phase equilibrium between liquid water and ice Ih modeled by the TIP4P/Ice interatomic potential using enhanced sampling molecular dynamics simulations. Our approach is based on the calculation of ice Ih-liquid free energy differences from simulations that visit reversibly both phases. The reversible interconversion is achieved by introducing a static bias potential as a function of an order parameter. The order parameter was tailored to crystallize the hexagonal diamond structure of oxygen in ice Ih. We analyze the effect of the system size on the ice Ih-liquid free energy differences and we obtain a melting temperature of 270 K in the thermodynamic limit. This result is in agreement with estimates from thermodynamic integration (272 K) and coexistence simulations (270 K). Since the order parameter does not include information about the coordinates of the protons, the spontaneously formed solid configurations contain proton disorder as expected for ice Ih. I. INTRODUCTION ture forms in an orientation compatible with the simulation box9. The study of phase equilibria using computer simulations is of central importance to understand the behavior of a given model. However, finding the thermodynamic condition at II. CRYSTAL STRUCTURE OF ICE Ih which two or more phases coexist is particularly hard in the presence of first order phase transitions. -
Rocio Del Mar, Sea of Cortez, Mexico + Other Articles Undercurrent, March
The Private, Exclusive Guide for Serious Divers March 2010 Vol. 25, No. 3 Rocio del Mar, Sea of Cortez, Mexico good liveaboard and fish life, with well-trained crew -- and sea lions IN THIS ISSUE: Dear Fellow Diver: Rocio del Mar, Mexico........ 1 I’m in the middle of the Sea of Cortez, surrounded by Two Dive Gear Recalls ..... 3 scores of darting sea lions. Their underwater barks seem as loud as if I heard them on land. So I came with a surprise, a Bonaire, Orlando, Mexico ... .4 double-horn Dive Alert that I blew underwater. And guess what? I stopped them in their tracks. Every sea lion stopped barking, Do Drugs Increase Your spun around and looked at me. If sea lions can look amazed, Risk of Bends? ............ 5 these did. I motioned to one curious guy by waving my hand toward me. “Come on over.” He moved a little closer every time Four Factors That Reduce I beckoned so I kept it up. When he got right up next to me, I Your DCS Risk ........... 6 spun my finger and he twirled away as if we had rehearsed it. Order Your Copy of Cockroach I turned around and my fellow divers were clapping. in My Regulator ............ 7 A trip to the Sea of Cortez has its marvels, and the first of them is that a trip on this spanking new liveaboard, New Dangers of Rebreather the 110-foot Rocio del Mar, begins by deplaning in Phoenix, Diving .................... 8 Arizona. Following is a four-hour van ride to Puerto Penasco, Where’s Your Customer Service, but no matter where you go, there’s always a van ride some- Scubapro? ............... -
Mulighetsstudie - Evakueringsrom
Mulighetsstudie - Evakueringsrom Ove Njå Rapport - 2017/140 © Kopiering er kun tillatt etter avtale med IRIS eller oppdragsgiver. International Research Institute of Stavanger AS er sertifisert etter et kvalitetssystem basert på NS-EN ISO 9001 og NS-EN ISO 14001:2004 www.iris.no © Kopiering er kun tillatt etter avtale med IRIS eller oppdragsgiver. International Research Institute of Stavanger AS er sertifisert etter et kvalitetssystem basert på NS-EN ISO 9001 og NS-EN ISO 14001:2004 Prosjektnummer: 7351039 Prosjektets tittel: Mulighetsstudie Evakueringsrom Oppdragsgiver(e): VRI Rogaland / Rogaland fylkeskommune og EUREKA/Align ISBN: 978-82-490-0889-6 Gradering: Åpen Kvalitetssikrer: Geir Sverre Braut, SuS Stavanger, 25.08.2017 Ove Njå Einar Leknes Prosjektleder Direktør IRIS Samfunnsforskning Prosjektet er støttet av Norges forskningsråd gjennom programmet Virkemidler for regional FoU og innovasjon – VRI © Kopiering er kun tillatt etter avtale med IRIS eller oppdragsgiver. International Research Institute of Stavanger AS er sertifisert etter et kvalitetssystem basert på NS-EN ISO 9001 og NS-EN ISO 14001:2004 © Kopiering er kun tillatt etter avtale med IRIS eller oppdragsgiver. International Research Institute of Stavanger AS er sertifisert etter et kvalitetssystem basert på NS-EN ISO 9001 og NS-EN ISO 14001:2004 International Research Institute of Stavanger www.iris.no Forord Tunnelsikkerhet har vært viktig i Rogaland siden Arne Rettedal gjennom sitt virke i Rogaland fylkeskommune fikk bygget Rennfast-tunnelene. Det var nybrottsarbeid, hvor tunnelbrann ikke ble ansett som styrende for beredskapen. Ulykker inntraff, men det ble ikke de samme hendelsene som man erfarte i Sør-Europa. En brann i Mastrafjordtunnelen i 2006 kunne fått fatale følger, men heldigvis klarte Kystbussen å snu i en havarinisje like før alle ble innhyllet i røyk. -
Hele Rapporten Og Dens Enkelte Deler
TØI rapport 1542/2016 Tor-Olav Nævestad Karen Ranestad Beate Elvebakk Sunniva Meyer Kartlegging av kjøretøybranner i norske vegtunneler 2008-2015 TØI-rapport 1542/2016 Kartlegging av kjøretøybranner i norske vegtunneler 2008-2015 Transportøkonomisk institutt (TØI) har opphavsrett til hele rapporten og dens enkelte deler. Innholdet kan brukes som underlagsmateriale. Når rapporten siteres eller omtales, skal TØI oppgis som kilde med navn og rapportnummer. Rapporten kan ikke endres. Ved eventuell annen bruk må forhåndssamtykke fra TØI innhentes. For øvrig gjelder åndsverklovens bestemmelser. ISSN 0808-1190 ISBN 978-82-480-1823-0 Papirversjon ISBN 978-82-480-1821-6 Elektronisk versjon Oslo, desember 2016 Tittel: Kartlegging av kjøretøybranner i norske Title: Vehicle fires in Norwegian road tunnels vegtunneler 2008-2015 2008-2015 Forfattere: Tor-Olav Nævestad Authors: Tor-Olav Nævestad Karen Ranestad Karen Ranestad Beate Elvebakk Beate Elvebakk Sunniva Meyer Sunniva Meyer Dato: 12.2016 Date: 12.2016 TØI-rapport 1542/2016 TØI Report: 1542/2016 Sider: 96 Pages: 96 ISBN papir: 978-82-480-1823-0 ISBN Paper: 978-82-480-1823-0 ISBN elektronisk: 978-82-480-1821-6 ISBN Electronic: 978-82-480-1821-6 ISSN: 0808-1190 ISSN: 0808-1190 Finansieringskilde: Statens vegvesen, Financed by: Norwegian Public Roads Vegdirektoratet Administration Prosjekt: 4398 – Vegtunnelbrann2016 Project: 4398 – Vegtunnelbrann2016 Prosjektleder: Tor-Olav Nævestad Project Manager: Tor-Olav Nævestad Kvalitetsansvarlig: Rune Elvik Quality Manager: Rune Elvik Fagfelt: 24 Sikkerhet og organisering Research Area: 24 Safety and organisation Emneord: Vegtunnel Keywords: Road tunnels Branner Fires Undersjøiske vegtunnel Undersea tunnel Tunge kjøretøy Heavy vehicles Sammendrag: Summary: Det er godt over 1100 vegtunneler i Norge. -
Freezing in Naples Underground
THE ARTIFICIAL GROUND FREEZING TECHNIQUE APPLICATION FOR THE NAPLES UNDERGROUND Giuseppe Colombo a Construction Supervisor of Naples underground, MM c Technicalb Director MM S.p.A., via del Vecchio Polit Abstract e Technicald DirectorStudio Icotekne, di progettazione Vico II S. Nicola Lunardi, all piazza S. Marco 1, The extension of the Naples Technical underground Director between Rocksoil Pia S.p.A., piazza S. Marc Direzionale by using bored tunnelling methods through the Neapo Cassania to unusually high heads of water for projects of th , Pietro Lunardi natural water table. Given the extreme difficulty of injecting the mater problem of waterproofing it during construction was by employing artificial ground freezing (office (AGF) district) metho on Line 1 includes 5 stations. T The main characteristics of this ground treatment a d with the main problems and solutions adopted during , Vittorio Manassero aspects of this experience which constitutes one of Italy, of the application of AGF technology. b , Bruno Cavagna e c S.p.A., Naples, Giovanna e a Dogana 9,ecnico Naples 8, Milan ion azi Sta o led To is type due to the presence of the Milan zza Dante and the o 1, Milan ial surrounding thelitan excavation, yellow tuff, the were subject he stations, driven partly St taz Stazione M zio solved for four of the stations un n Università ic e ds. ip Sta io zione Du e omo re presented in the text along the major the project examples, and theat leastsignificant in S t G ta a z r io iibb n a e Centro lldd i - 1 - 1. -
Report 2008/05 Pacific Earthquake Engineering Research Center College of Engineering University of California, Berkeley August 2008
PACIFIC EARTHQUAKE ENGINEERING RESEARCH CENTER Performance-Based Earthquake Engineering Design Evaluation Procedure for Bridge Foundations Undergoing Liquefaction-Induced Lateral Ground Displacement Christian A. Ledezma and Jonathan D. Bray University of California, Berkeley PEER 2008/05 AUGUST 2008 Performance-Based Earthquake Engineering Design Evaluation Procedure for Bridge Foundations Undergoing Liquefaction-Induced Lateral Ground Displacement Christian A. Ledezma and Jonathan D. Bray, Ph.D., P.E. Department of Civil and Environmental Engineering University of California, Berkeley PEER Report 2008/05 Pacific Earthquake Engineering Research Center College of Engineering University of California, Berkeley August 2008 ABSTRACT Liquefaction-induced lateral ground displacement has caused significant damage to pile foundations during past earthquakes. Ground displacements due to liquefaction can impose large forces on the overlying structure and large bending moments in the laterally displaced piles. Pile foundations, however, can be designed to withstand the displacement and forces induced by lateral ground displacement. Piles may actually “pin” the upper layer of soil that would normally spread atop the liquefied layer below it into the stronger soils below the liquefiable soil layer. This phenomenon is known as the “pile-pinning” effect. Piles have been designed as “pins” across liquefiable layers in a number of projects, and this design methodology was standardized in the U.S. bridge design guidance document MCEER/ATC-49-1. A number of simplifying assumptions were made in developing this design procedure, and several of these assumptions warrant re-evaluation. In this report, some of the key assumptions involved in evaluating the pile-pinning effect are critiqued, and a simplified probabilistic design framework is proposed for evaluating the effects of liquefaction-induced displacement on pile foundations of bridge structures. -
JBT Lecture Paper
JACKED BOX TUNNELLING Using the Ropkins System TM , a non-intrusive tunnelling technique for constructing new underbridges beneath existing traffic arteries DR DOUGLAS ALLENBY, Chief Tunnelling Engineer, Edmund Nuttall Limited JOHN W T ROPKINS, Managing Director, John Ropkins Limited Lecture presented at the Institution of Mechanical Engineers Held at 1 Birdcage Walk, London On Wednesday 17 October 2007 © Institution of Mechanical Engineers 2007 This publication is copyright under the Berne Convention and the International Copyright Convention. All rights reserved. Apart from any fair dealing for the purpose of private study, research, criticism or review, as permitted under the Copyright, Designs and Patent Act, 1988, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without the prior permission of the copyright owners. Reprographic reproduction is permitted only in accordance with the terms of licenses issued by the Copyright Licensing Agency, 90 Tottenham Court Road, London W1P 9HE. Unlicensed multiple copying of the contents of the publication without permission is illegal. Jacked Box Tunnelling using the Ropkins System TM , a non-intrusive tunnelling technique for constructing new underbridges beneath existing traffic arteries Dr Douglas Allenby BSc(Hons) PhD CEng FICE FIMechE FGS, Chief Tunnelling Engineer, Edmund Nuttall Limited John W T Ropkins BSc CEng MICE, Managing Director, John Ropkins Limited The Ropkins System TM is a non-intrusive tunnelling technique that enables engineers to construct underbridges beneath existing traffic arteries in a manner that avoids the cost and inconvenience of traffic disruption associated with traditional construction techniques. The paper outlines a tunnelling system designed to install large open ended rectangular reinforced concrete box structures at shallow depth beneath existing railway and highway infrastructure. -
Modeling the Ice VI to VII Phase Transition
Modeling the Ice VI to VII Phase Transition Dawn M. King 2009 NSF/REU PROJECT Physics Department University of Notre Dame Advisor: Dr. Kathie E. Newman July 31, 2009 Abstract Ice (solid water) is found in a number of different structures as a function of temperature and pressure. This project focuses on two forms: Ice VI (space group P 42=nmc) and Ice VII (space group Pn3m). An interesting feature of the structural phase transition from VI to VII is that both structures are \self clathrate," which means that each structure has two sublattices which interpenetrate each other but do not directly bond with each other. The goal is to understand the mechanism behind the phase transition; that is, is there a way these structures distort to become the other, or does the transition occur through the breaking of bonds followed by a migration of the water molecules to the new positions? In this project we model the transition first utilizing three dimensional visualization of each structure, then we mathematically develop a common coordinate system for the two structures. The last step will be to create a phenomenological Ising-like spin model of the system to capture the energetics of the transition. It is hoped the spin model can eventually be studied using either molecular dynamics or Monte Carlo simulations. 1 Overview of Ice The known existence of many solid states of water provides insight into the complexity of condensed matter in the universe. The familiarity of ice and the existence of many structures deem ice to be interesting in the development of techniques to understand phase transitions.