Home About us Contact
|
Home About us Contact | ||
|
|
||
Tunnel
Kinds of Tunnel Terms modified by Tunnel Selected AbstractsSimultaneous Measurements of Ion Temperature by Segmented Tunnel and Katsumata ProbeCONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-7 2008J. Adámek Abstract Simultaneous measurements of the ion temperature by the segmented tunnel and Katsumata probe in the CASTOR tokamak are reported. The segmented tunnel probe measures two ion saturation currents Iseg 1, Iseg 2 towards two segments of the tunnel. The axis of the tunnel is aligned with the total magnetic field. The value of the ratio of these two currents combined with the results of the PIC modeling provides the ion temperature. Design and experimental arrangement of the Katsumata probe enable us to measure the pure ion current by sweeping the applied voltage. The ion temperature is then estimated from the exponential part of the measured I , V characteristic. Simultaneous measurements of the ion temperature by the segmented tunnel and Katsumata probe agree within a few eV. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] First and second tube of the Tauern TunnelGEOMECHANICS AND TUNNELLING, Issue 4 2010Article first published online: 5 AUG 2010 After scarcely four years of construction work, the second Tauern Tunnel tube on the A10 was opened for traffic on the 30 April 2010. The 6, 400 m long mined tunnel was constructed in only 22 months by Porr Tunnelbau GmbH. The new valley tube of the Tauern Tunnel, with its seven stopping niches, 26 cross passages, full transverse ventilation, and the light, reflective coating on the tunnel walls, is among the most modern tunnels in Austria. Nach knapp vierjähriger Bauzeit wurde am 30. April 2010 die zweite Tauerntunnelröhre derA10 eröffnet und in Betrieb genommen. Der 6.400 m lange bergmännische Vortrieb wurde in nur 22 Monaten von der Porr Tunnelbau GmbH hergestellt. Die neue Talröhre des Tauerntunnels zählt mit seinen sieben Abstellnischen, 26 Querschläge, einer Vollquerlüftung und der hellen, reflektierenden Tunnelwandbeschichtung zu den modernsten Tunnel Österreichs. [source] Consequences of EC7 on the design of tunnelsGEOMECHANICS AND TUNNELLING, Issue 1 2010Article first published online: 24 FEB 2010 The cover picture shows the assembly of an arch formwork carriage on contract H2-2 Radfeld Mitte, where a 1,600 m long cut-and-cover tunnel is being built for the Lower Inn Valley railway The Brenner Railway Company is currently constructing about 40 km of new line between Kundl/Radfeld and Baumkirchen in the Lower Inn valley in Austria. Almost 32 km of this route will run in tunnels, troughs, box-section cut-and-cover and in a gallery. Track installation in the flatlands of the Tyrol is also on schedule and the new line will be open for traffic in 2012. (Photo: ÖBB H2-2, Arge D2 Consult , Hyder Consulting GmbH). Das Titelbild zeigt den Aufbau eines Gewölbeschalwagens im Baulos H2-2 Radfeld Mitte. Dort ist für die Unterinntalbahn unter anderem ein 1.600 m langer Tunnel in offener Bauweise zu errichten. Zwischen Kundl/Radfeld und Baumkirchen erstellt die ÖBB-Infrastruktur AG rund 40 km zweigleisige Neubautrasse. Fast 32 km dieser Anlage befinden sich in Tunneln, Wannen, Unterflurtrassen und in einer Galerie. Der Schienenausbau im Tiroler Unterland liegt im Zeitplan, die neue Bahnstrecke wird 2012 in Betrieb gehen (Foto: ÖBA H2-2, Arge D2 Consult , Hyder Consulting GmbH). [source] Geomechanics and Tunnelling 2/2010GEOMECHANICS AND TUNNELLING, Issue 1 2010Article first published online: 24 FEB 2010 Semmering and Koralm tunnels Neue Südbahn, Semmering und Koralm Tunnel F. Bauer: Investment in the Austrian rail network , overview of new and upgrading projects , Investitionen in das österreichische Schienennetz , Überblick Neu- und Ausbauvorhaben G. Gobiet and D. Haas: New Semmering Base Tunnel project , an interdisciplinary challenge , Semmering Basistunnel Neu , eine interdisziplinäre Herausforderung A. Fasching, R. Vanek, Th. Stadlmann, P. Reichl, G. Domberger, G. Forstinger and O. Wagner: New Semmering Base Tunnel , the investigation programme 2008/2009 and the knowledge gained in the areas of geology, hydrogeology and geotechnical engineering , Semmering-Basistunnel Neu , Das Erkundungsprogramm 2008/2009 und die daraus gewonnenen Erkenntnisse auf den Gebieten der Geologie, Hydrogeologie und Geotechnik J. Daller, A. Vigl and O. Wagner: New Semmering Base Tunnel , the current state of tunnel design taking the newest investigation results into account , Semmering-Basistunnel Neu , Aktueller Stand der Tunnelplanung unter Berücksichtigung der neuesten Erkundungsergebnisse R. Bopp, V. Langer, Ch. Neumann and O. Wagner: The ventilation and tunnel safety concept for the New Semmering Base Tunnel , Das Lüftungs- und Tunnelsicherheitskonzept für den Semmering-Basistunnel Neu G. Harer and J. Koinig: Current state of design, investigation and construction work at the Koralm Tunnel , Aktueller Stand der Planungs-, Erkundungs- und Ausführungsarbeiten beim Koralmtunnel P. Schubert, H. Hölzl, P. Sellner and F. Fasching: Geomechanical knowledge gained from the Paierdorf Investigation Tunnel in the section through the Lavanttal main fault zone , Geomechanischer Wissenszuwachs durch den Erkundungstunnel Paierdorf im Abschnitt der Lavanttaler Hauptstörungszone D. Handke, M. Nolden, K. Mussger and A. Steidl: Solution methods for the design and construction of contract KAT 3 , Lösungsansätze für Planung und Bauausführung des Bauloses KAT 3 M. Vill, H. Wagner, A. Schweighofer, H. Huber, W. Pichler and J. Kollegger: New development of a crack-limited invert slab , Neuentwicklung der rissebeschränkten Sohlplatte M. Stopka: Hengsberg Tunnel , the construction contract as seen by the contractor , Hengsbergtunnel , der Bauvertrag aus Sicht des Auftragnehmers T. Schachinger, H. Gaube and G. Krainer: Results from the Untersammelsdorf test field for the planning of the tunnelling work , Erkenntnisse aus dem Versuchsfeld Untersammelsdorf für die Gestaltung der Vortriebsmaßnahmen K. Chmelina and K. Rabensteiner: Improvement of the safety and profitability of tunnel drives through the use of automated measurement and alarm systems , examples in practice , Verbesserung der Sicherheit und Wirtschaftlichkeit von Tunnelvortrieben durch den Einsatz automatisierter Mess- und Alarm-systeme , Ausführungsbeispiele [source] Big diameter tunnelling beneath low rock cover.GEOMECHANICS AND TUNNELLING, Issue 3 2009Bau eines Großtunnels unter geringer Felsüberdeckung Abstract The Clem Jones Tunnel (former North-South Bypass Tunnel) is the first project to get underway as part of Brisbane's transport plan which aims to improve the urban road network. The total length to be excavated is 6.8 km which includes 4.8 km of driven tunnel and associated road connections. Construction commenced in August 2006 with project completion targeted well before the contractual completion date of October 2010. Due to the local geology, in particular the hard Brisbane tuff and Neranleigh-Fernvale formation a combination of tunnel excavation methods are used. The majority of the tunnel is excavated by two tunnel boring machines in rock having a compressive strength of between 80 and 150 MPa. Ten roadheaders are excavating the remaining tunnels such as ramps, access tunnels, cross passages and merges. A major challenge arose during the planning of the initial mainline excavation underneath the Royal National Association Showground in Bowen Hills. This section contains low rock cover and historical maps indicate that the Showground is located within a former topographic depression (alluvial valley) where a creek once flowed through. Due to traffic merge design requirements, both TBM and roadheader excavation methods were required to be used in this challenging geological profile. The answer was to stabilise the alluvium above both TBM section tunnels from the surface prior to excavation and to operate the TBM in single shield mode with immediate grouting of annular void from the tail shield. In addition, the roadheader section of tunnel required additional support by spiles and canopy tubes installed from the tunnel face. Der Clem Jones Tunnel (ehemals North South Bypass Tunnel) ist das erste in Angriff genommene Projekt des Brisbane-Transportplans. Dieser Plan hat das Ziel, das städtische Straßennetzwerk zu verbessern. Insgesamt wird eine Strecke von 6,8 km aufgefahren, einschließlich 4,8 km bergmännische Tunnel und zugehörige Straßenanbindungen. Die Bauarbeiten begannen im August 2006, und die Fertigstellung des Projekts ist deutlich vor dem vertraglich vereinbarten Fertigstellungstermin im Oktober 2010 geplant. Der größte Teil der Tunnel wird durch zwei Tunnelbohrmaschinen im Hartgestein mit einer Druckfestigkeit zwischen 80 und 150 MPa ausgebrochen. Zehn Teilschnittmaschinen fahren die übrigen Tunnel wie Rampen, Zugangstunnel, Querschläge und Verbindungen auf. Eine große Herausforderung ergab sich während der Planung des Haupttunnelvortriebs unter dem Ausstellungsgelände der Royal National Association in Bowen Hills. Dieses Gebiet besitzt eine geringe Felsüberdeckung, und aus historischen Karten weiß man, dass das Ausstellungsgelände in einer ehemaligen topografischen Senke (alluviales Tal) liegt, durch die früher ein Bach floss. Aufgrund von Verkehrsplanungsanforderungen war es notwendig, sowohl Tunnelbohrmaschinen als auch Teilschnittmaschinen in dieser schwierigen geologischen Situation zu verwenden. Die Lösung bestand darin, das Schwemmland über beiden TBMTunneln von oben her zu stabilisieren und die Tunnelbohrmaschine in der Einfachschildbetriebsart zu fahren, wobei der Ringspalt vom Schildschwanz aus verpresst wird. Die durch Teilschnittmaschinen ausgebrochenen Tunnel mussten außerdem zusätzlich durch Spieße und eine Rohrschirmsicherung gestützt werden. [source] The influence of grout and bentonite slurry on the process of TBM tunnelling.GEOMECHANICS AND TUNNELLING, Issue 3 2009Der Einfluss von Ringspaltmörtel und Bentonitsuspension auf den TBM-Vortrieb Abstract The bentonite and grout flow around a TBM is elaborated, as well as grout flow along the lining. The calculated grout flow along the lining is compared with the results of measurements. Measurement data for the flow around the TBM are not available. Both the bentonite and the grout are modelled as a Bingham liquid and it will be shown that, due to the relatively low flow velocities, the yield stress is the governing parameter. The results of the calculations show that both the flow around the TBM and the flow around the lining may significantly influence loading on the TBM, the soil, and the lining. The bentonite and grout flow around the TBM may result in a lower volume loss than calculated when assuming that the soil follows the tapered TBM. The grout flow and especially grout consolidation lead to lower pressures around the lining if the tunnel is constructed in sandy soil. Der Bentonit- und Mörtelfluss um eine TBM und der Mörtelfluss entlang der Auskleidung werden diskutiert. Der berechnete Mörtelfluss entlang der Auskleidung wird mit Messdaten verglichen. Für die Strömungen um eine TBM existieren keine Messdaten. Sowohl der Bentonit als auch der Mörtel werden als Bingham Flüssigkeit modelliert, und es wird gezeigt, dass wegen der relativ niedrigen Strömungsgeschwindigkeiten die Fließspannung der bestimmende Parameter ist. Die Ergebnisse der Berechnungen zeigen, dass sowohl die Strömung um die TBM als auch entlang der Auskleidung einen bedeutenden Einfluss auf die Belastung der TBM, des Bodens und der Auskleidung haben. Der Bentonit- und Mörtelfluss um die TBM kann einen niedrigeren Volumenverlust zur Folge haben als berechnet, wenn man annimmt, dass der Boden der konisch zulaufenden TBM folgt. Der Mörtelfluss und besonders die Mörtelverfestigung führen zu einem niedrigeren Druck auf die Auskleidung wenn der Tunnel in sandigem Boden errichtet wird. [source] Basic Surveying of the Koralm TunnelGEOMECHANICS AND TUNNELLING, Issue 4 2008Arnold Eder The "Koralm tunnel basic network" had to be prepared for the design, construction, and construction supervision of the ÖBB railway project "Koralmbahn Graz-Klagenfurt" with the 32.8 km long Koralm tunnel as its core piece. This network is based on the "primary network" which is integrated into a network of GPS permanent stations and was or will be complemented as required. Since the project area covers two meridian zones of the national system, it was necessary to create a projection in a separate meridian zone for planar calculations. The paper describes the preparation, surveying and calculation of this network. In addition, it includes procedure instructions for the use of the network by planners and construction companies. Since the network has to be adapted to each construction phase, it has to be continuously developed. This will be described too. All data are managed by means of an ArcGIS server. Grundvermessung des Koralmtunnels Das Koralmtunnel-Grundlagennetz wurde für die Planung, den Bau und die Bauüberwachung des Koralmtunnels erstellt. Der 32,8 km lange Koralmtunnel bildet das Schlüsselbauwerk im Rahmen der neuen Eisenbahnverbindung Koralmbahn zwischen Graz und Klagenfurt. Das Netz baut auf einem Grundnetz, das in einem permanenten GPS-Stationsrahmen integriert ist, und wird je nach Projektfortschritt und -anforderungen erweitert. Durch die Lage des Projekts über zwei Meridianstreifen des öffentlichen Systems war es außerdem erforderlich, eine neue, ebene Projektion zu entwerfen. Der Beitrag beschreibt die Vorbereitungen für dieses System, die erforderlichen Vermessungs- und Berechnungstätigkeiten sowie die Hinweise für den Gebrauch dieses Netzes durch Planer oder bauausführende Firmen. Da in jeder Projektphase eine ständige Adaptierung des Netzes unabdingbar ist, werden auch Hinweise zu diesen Tätigkeiten gegeben. Alle Daten werden mithilfe eines ArcGIS-Servers verwaltet. [source] Handling of Excavated Material from the Koralm Tunnel in StyriaGEOMECHANICS AND TUNNELLING, Issue 4 2008Peter Pichler The Koralm Railway Line represents an essential section of the Pontebbana corridor between Graz and Klagenfurt. It creates new capacities and significantly improved conditions for the freight transportation. Furthermore, the travel time of the passenger traffic will be considerably reduced. The heart of the Koralm railway Line is the Koralm tunnel with a length of approximately 32.8 km. Right from the first steps of planning it became clear that there would be a demand for an economical and ecological handling of the excavated materials. So a specific programme was performed, which is presented in this paper. The experiences made will strongly influence the programme of construction and the detailed design of the future main tunnel structure. Umgang mit dem Ausbruchsmaterial des Koralmtunnels in der Steiermark Die Koralmbahn, welche zwischen Graz und Klagenfurt ein maßgebliches Teilstück im Rahmen des Pontebbana-Korridors darstellt, schafft neue Kapazitäten und deutlich verbesserte Voraussetzungen für den Bahngüterverkehr und wird die derzeitige Fahrzeit im Personenverkehr erheblich reduzieren. Der Koralmtunnel stellt mit einer Länge von rund 32,8 km das Kernstück der neuen Koralmbahn dar. Bereits seit den frühesten Planungsphasen wurde konsequent an einem Programm für den wirtschaftlichen und umweltfreundlichen Umgang mit den Tunnelausbruchsmaterialien gearbeitet. Die Erkenntnisse aus den bisherigen Untersuchungen sind im vorliegenden Artikel zusammengefasst. Diese Erkenntnisse fließen maßgeblich in die Bauablauf- und Detailplanungen des zukünftigen Haupttunnels ein. [source] A Numerical Simulation Model for Shield Tunnelling with Compressed Air SupportGEOMECHANICS AND TUNNELLING, Issue 3 2008Felix Nagel Dipl.-Ing. This paper is concerned with a numerical simulation model (ekate) specifically designed for shield tunnelling in fully and partially saturated soils based upon the Finite Element Method (FEM). The model considers all relevant components , the soil, the lining, the tail void grouting, the hydraulic jacks and different types of face support , involved in shield tunnelling. The surrounding soft soil is formulated as a three-phase material, consisting of the soil skeleton, pore water and air. This model allows for the simulation of consolidation processes in partially saturated soils as well as of flow of compressed air often used as temporary face support during repair interventions at the cutting wheel. Despite the complexity connected with the relatively high degree of realism of the simulation model, only little effort is required from the user to establish a realistic 3D model for shield tunnelling. To this end an automatic model generator has been developed which allows for a user friendly generation of the discretized model including all components involved and to investigate variants with a minimum effort for the user. The model allows for realistic predictions of settlements and also provides information on deformations and stresses in the ground, the lining and the TBM, respectively. In addition to its use as a prognosis tool in the design process, in particular for tunnelling projects in sensitive urban areas, the model also may be used to assist the driving and steering process in mechanized tunnelling. The paper provides an overview over the main components of the model, the automatic model generator and the tri-phasic representation of the soil. A simulation of a compressed air intervention of a shield tunnel in soft soil demonstrates the applicability of the model. Ein numerisches Simulationsmodell für druckluftgestützte Schildvortriebe In diesem Beitrag wird ein Simulationsmodell basierend auf der Methode der Finiten Elemente (FEM) für die Berechnung schildvorgetriebener Tunnel in un-, voll- und teilgesättigten Böden vorgestellt. In diesem numerischen Modell werden alle beim maschinellen Tunnelbau wesentlichen Komponenten , der Boden, der Ausbau, die Schildschwanzverpressung, die Vortriebspressen sowie unterschiedliche Arten der Ortsbruststützung , wirklichkeitsnah berücksichtigt. Der Baugrund wird im Simulationsmodell als dreiphasiges Material modelliert, bestehend aus dem Korngerüst, dem Porenwasser und der Porenluft. Diese Materialformulierung für den Baugrund ermöglicht die Analyse von Konsolidierungsprozessen in teilgesättigten Böden ebenso wie von Strömungsvorgängen im Boden bei Verwendung von Druckluft als temporärer Ortsbruststützung. Druckluft wird häufig beim Wechsel von Schneidwerkzeugen eingesetzt. Ungeachtet der Komplexität des Modells, die mit der relativ wirklichkeitsnahen Abbildung des Vortriebsgeschehens verbunden ist, ist nur ein sehr geringer Aufwand für die Modellgenerierung erforderlich. Um diesen Eingabeaufwand auf ein Minimum zu reduzieren, wurde ein automatischer Modellgenerator entwickelt, der den Ingenieur bei der Eingabe unterstützt und die Untersuchung von Planungsalternativen deutlich vereinfacht. Das Modell ermöglicht wirklichkeitsnahe Prognosen von Bodenbewegungen und Beanspruchungen, wie sie für die Planung von Vortrieben insbesondere unter setzungsempfindlichen, innerstädtischen Gebieten erforderlich sind. Darüber hinaus stellt das Modell ein wertvolles Hilfsmittel bei der vortriebsbegleitenden Steuerung von Vortriebsmaschinen in Lockergestein dar. Neben den wesentlichen Komponenten des numerischen Modells, des Modellgenerators und der Dreiphasen-Formulierung für den Boden enthält der Beitrag als prototypisches Anwendungsbeispiel die Simulation einer Druckluftintervention in Lockergestein. [source] Steady Flow into a Tunnel with a Constant Pressure HeadGROUND WATER, Issue 5 2000ShiZhong Lei No abstract is available for this article. [source] In situ hydraulic tests in the active fault survey tunnel, Kamioka Mine, excavated through the active Mozumi-Sukenobu Fault zone and their hydrogeological significanceISLAND ARC, Issue 4 2006Tsuyoshi Nohara Abstract The spatial hydrogeological and structural character of the active Mozumi-Sukenobu Fault (MSF) was investigated along a survey tunnel excavated through the MSF in the Kamioka Mine, central Japan. Major groundwater conduits on both sides of the MSF are recognized. One is considered to be a subvertical conduit between the tunnel and the surface, and the other is estimated to be a major reservoir of old meteoric water alongside the MSF. Our studies indicate that part of the MSF is a sub-vertical continuous barrier that obstructs younger meteoric water observed in the south-eastern part of the Active Fault Survey Tunnel (AFST) and water recharge to the rock mass intersected by the north-western part of the AFST. The MSF might be a continuous barrier resulting in the storage of a large quantity of older groundwater to the northwest. The observations and results of in situ hydraulic tests indicate that the major reservoir is not the fault breccia associated with the northeast,southwest trending faults of the MSF, but the zone in which blocks of fractured rocks occur beside high angle faults corresponding to X shears whose tectonic stress field coincides with the present regional stress field and antithetic Riedel shears of the MSF. The results from borehole investigations in the AFST indicate that secondary porosity is developed in the major reservoir due to the destruction of filling minerals and fracture development beside these shears. The increase in hydraulic conductivity is not directly related to increased density of fractures around the MSF. Development of secondary porosity could cause the increase in hydraulic conductivity around the MSF. Our results suggest that minor conduits of the fracture network are sporadically distributed in the sedimentary rocks around the MSF in the AFST. [source] AFRICA: Light at the End of TunnelAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 3 2010Article first published online: 4 MAY 2010 No abstract is available for this article. [source] Simple Repair of Aortico-Left Ventricular Tunnel in a Newborn with Early Prenatal DiagnosisJOURNAL OF CARDIAC SURGERY, Issue 4 2008Roland Henaine M.D. Early recognition of ALVT by antenatal ultrasound allows prompt neonatal management and avoidance of harmful aortic valve regurgitation. The present case is unique because of the conjunction of very early antenatal diagnosis, prompt postnatal management, early surgical repair on the sixth day of life, direct closure from the aorta of the aortic orifice only, and optimal postoperative course with excellent mid-term result. [source] Organization and Management in an Anglo-French Consortium: The Case of Transmanche-LinkJOURNAL OF MANAGEMENT STUDIES, Issue 5 2000Graham M. Winch This paper presents the results of a comparative organizational assessment of the behaviour and organization of the British and French managers who constructed the Channel Tunnel. In the context of a common adhocratic organization, a principal components analysis of the survey results differentiates the British and French respondents on five dimensions: fonceur/procedural; competitive/collegial; involved/distanced; individualistic/supportive; and stress. These quantitative results are supported by qualitative data from interviews and open-ended questions. A preliminary explanation of the results in terms of a configurational analysis of the differences between the British and French managers surveyed is then offered. The paper argues that an organizational assessment methodology is compatible with societal approaches which attempt to understand nationally distinctive configurations of organization and management. [source] Biochemical and Structural Characterization of the Tautomycetin Thioesterase: Analysis of a Stereoselective Polyketide Hydrolase,ANGEWANDTE CHEMIE, Issue 33 2010Jamie Ein enger Tunnel: Struktur- und biochemische Analyse der Tautomycetin-Thioesterase (TE) lieferten die erste hoch aufgelöste Struktur einer TE mit einer linearen Kette als Endstück in der Polyketidbiosynthese und zeigten, dass das Enzym stereoselektiv ist und eine engere Substratkammer aufweist als Makrolactone bildende Thioesterasen. [source] Response of Molecular Junctions to Surface Plasmon Polaritons,ANGEWANDTE CHEMIE, Issue 33 2010Gilad Noy Tunnel in die Freiheit: Durch Laserbestrahlung erzeugte Plasmonen beeinflussen die Leitfähigkeit an einem molekularen Übergang mit ,schwebendem Draht" (siehe Bild). Die Stromzunahme, die von Wellenlänge und Laserleistung abzuhängen scheint, ist in halbquantitativer Übereinstimmung mit theoretischen Modellen auf der Grundlage eines photonenvermittelten Tunnelmechanismus. [source] Bahnsteigerweiterung der U6 unter dem neuen Rathaus in München , Spritzbetonvortrieb mit VereisungBAUTECHNIK, Issue 7 2005Jochen Fillibeck Dr.-Ing. Im Rahmen der Infrastrukturmaßnahmen für den Bau des neuen Fußballstadions in Fröttmaning wurde es erforderlich, die Bahnsteige der U-Bahnlinie U6 unter dem Rathaus in München zu erweitern. Nach dem Entwurf des Baureferats der Landeshauptstadt München wurde hierzu parallel und im direkten Anschluß an die beiden bestehenden Tunnelröhren je ein Tunnel in Spritzbetonbauweise unter atmosphärischen Bedingungen ausgeführt. Die Vortriebe liegen in einem vertikalen Abstand von ca. 10 m zum Münchner Rathaus. Zur Sicherung der Firste und zur Reduzierung der Verformungen wurden im Rahmen eines Sondervorschlags Vereisungsschirme vorgesehen, die von einem über der Firste befindlichen Pilotstollen aus hergestellt wurden. Für die erfolgreiche Umsetzung des Bauvorhabens war es entscheidend, welche Verformungen , Hebungen in der Gefrierphase und Setzungen während des Vortriebs , sich mit dem Baufortschritt einstellen. Dies wurde vorab anhand von Frostversuchen im Labor und mit FE-Berechnungen untersucht. Durch einen Vergleich der Berechnungsergebnisse mit den umfangreichen Kraft- und Verformungsmessungen während des Vortriebs konnte zu jedem Zeitpunkt ein verformungsarmer Tunnelvortrieb mit tolerierbaren Baugrundverformungen sichergestellt werden. Im folgenden Beitrag werden die wesentlichen Berechnungen und Meßergebnisse zu den Baugrundverformungen und zur Wasserhaltung und die Maßnahmen zur Reduzierung der Frosthebungen erläutert. Ferner werden durch einen Vergleich der Bau- und Berechnungsweisen der alten Bestandstunnels mit dem neuen Erweiterungstunnel die mit der Spritzbetonbauweise einhergehenden Entwicklungen im Tunnelbau veranschaulicht. Platform extension of the subway U6 below the historical town hall in Munich , shotcrete method combined with ground freezing. The construction of the new football stadium in Munich-Fröttmaning made it necessary to extend the platform of the subway station U6 "Marienplatz" below the historical town hall of Munich. For this, two new tunnels for pedestrians were driven parallel to the existing subway tunnels. They were planned as shotcrete construction and driven under atmospheric conditions. The tunnels have a vertical distance of approx. 10 m to the foundation of the town hall. Artificial ground freezing was used to guarantee the stability and safety of the tunnel roof and to reduce the deformations. The freezing pipes were implemented in a smaller pilot tube lateral above the tunnels. Both the magnitude of the frost heave displacements and the settlements had to be predicted prior to undertake the construction. Therefore frost heave tests and FE-computations were carried out. During the construction process these results were permanently compared to measurements in order to control and ensure tolerable deformations. In the following contribution the substantial computations and results of measurement relating to the ground deformations and to the lowering of groundwater are described. Furthermore the methods for the reduction of the frost heave are explained. A comparison of the methods of construction and calculation of the old tunnels and the new tunnels illustrates the developments in tunnel construction resulting from the shotcrete method. [source] Bauwerks-Management-System (BMS) , Werkzeug zur Substanzerhaltung für VerkehrsbauwerkeBAUTECHNIK, Issue 10 2004Peter Haardt Dr.-Ing. Das Bundesfernstraßennetz beinhaltet eine große Anzahl von Brücken und anderen Ingenieurbauwerken, wie Tunnel, Lärmschutzeinrichtungen und Stützwände. Die für diese Bauwerke aufzustellenden Erhaltungsprogramme erfordern nicht nur erhebliche Geldmittel, sondern beeinflussen auch Wirtschaft und Gesellschaft insgesamt. Neben den ständig wachsenden Verkehrsbeanspruchungen zwingen die ungünstiger werdende Altersstruktur und der wirtschaftliche Einsatz der zur Verfügung stehenden Haushaltsmittel alle Beteiligten dazu, die Erhaltung der Bundesfernstraßen zu systematisieren, um auch zukünftig den Verkehrsteilnehmern eine ausreichende Qualität der Verkehrswege zu sichern. Diese Aufgabe wird durch die Anwendung eines umfassenden Management Systems (Bauwerks-Management-System, BMS) unterstützt und erleichtert. Das BMVBW realisiert ein umfassendes Bauwerks-Management-System mit Teil modulen für Bundes- und Länderverwaltungen, welches als Hilfsmittel für die Erstellung von Erhaltungsplanungen dient und als Controlling-Instrument die Realisierung von Zielen und Strategien ermöglicht. Angestrebt werden damit eine bundesweite Vereinheitlichung von Planungsverfahren sowie die Verbesserung der Wirtschaftlichkeit im Rahmen der Erhaltung der Bauwerke des Bundesfernstraßennetzes. Der Beitrag beschreibt neben den bereits existierenden Regelungen und Verfahren die aktuellen Entwicklungen von Verfahren zur Unterstützung der Erhaltungsplanungen, die derzeit für Computeranwendungen bereitgestellt werden. Wesentliche Einzelthemen sind Informationsbereitstellung, Entwicklung von Erhaltungsstrategien und Bewertungsverfahren auf Objekt- und Netzebene. Bridge Management System (BMS) , a tool for maintenance of highway structures. The federal road network of Germany contains a large number of highway structures like bridges, tunnels, retaining walls and others. The maintenance programs to be prepared for this purpose not only require a high budget, but also influence the economy and society as a whole. Due to growing volumes of traffic and higher weights of trucks, bridges are subjected to increasing loads which implies that maintenance costs will be rising in the future. Considering the fact that financial resources become continuously tighter, the maintenance costs have to be spent in a way to obtain the greatest possible benefits. This task will in the future be supported by the application of individual computer programs in the frame of a comprehensive Management System (Bridge Management System, BMS). Firstly, the BMS is to provide the Federal Ministry with an overview of the current situation at the overall network level, and allow it to come to financial requirements as well as strategies for realising long-term objectives. Secondly, the states and authorities are to be supplied with recommendations for performing improvements at the object level and the state network level in compliance with given strategies and budgetary restrictions. The paper describes the existing regulations as well as procedures for the support of maintenance planning which are currently being developed for computer application. Important topics are information technology, development of maintenance strategies and assessment procedures on object and network level. [source] Malmö City Tunnel, SchwedenBETON- UND STAHLBETONBAU, Issue 7 2010Article first published online: 30 JUN 2010 No abstract is available for this article. [source] Titelbild: Beton- und Stahlbetonbau 2/2007BETON- UND STAHLBETONBAU, Issue 2 2007Article first published online: 29 JAN 200 Das Titelbild zeigt die neu gebaute teilweise Überdeckelung der Konrad-Adenauer-Straße (B 14) in Stuttgart im Bereich der Innenstadt. Durch diese Baumaßnahme wurden knapp 2000 m2 zusätzliche Grünfläche im innerstädtischen Raum geschaffen. Das Wilhelmspalais und das Hauptstaatsarchiv konnten in hoher ästhetischer Qualität mit dem Akademiegarten verbunden werden, was einen großen städtebaulichen Gewinn bedeutet. Das Fernziel ist die vollständige Verlegung der Konrad-Adenauer-Straße in einen Tunnel. Durch die teilweise Überdeckelung konnte die Situation kurzfristig und mit relativ niedrigen Kosten verbessert werden. Die Verwendung von Spannbetonfertigteilen ermöglichte eine sehr schnelle Erstellung der Baumaßnahme, so dass nach nur fünfmonatiger Planungszeit und ebenso langer Bauzeit die Einweihung kurz vor der Fußballweltmeisterschaft im Juni 2006 erfolgen konnte. Mehr darüber im Bericht ab Seite 114 (Foto: Zooey Braun, Stuttgart). [source] ChemInform Abstract: A New Molybdenum(V) Phosphate with a Tunnel: Hydrothermal Synthesis and Characterization of (C2N2H10)6 [Na2Mo12O31(PO4) (HPO4)2(H2PO4)5] ×4H2O.CHEMINFORM, Issue 32 2008Shao-Yu Mao Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Failure Mechanism of Deformed Concrete Tunnels Subject to Diagonally Concentrated LoadsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2009Wei He Based on the experimental findings, an extended discussion is carried out to select a rational compressive model for concrete that represents the dominant failure modes of deformed concrete tunnels. Three main dominant final failure modes are described: structural failure due to the plastic rotation of softening hinges, tensile failure caused by localized cracks, and material failure due to concrete deterioration. A parametric analysis of the material properties of concrete shows that the compressive strength of concrete has a dominant effect on the load-carrying capacity, although the compressive fracture energy of concrete remarkably influences the post-peak deformation behavior of the tunnel. Moreover, the soil pressure, which is regarded as a distributed external load, plays an important role in controlling the final failure modes and the deformation behavior of concrete tunnels. The size effect on the load-carrying capacities of different-sized concrete tunnels is also discussed based on the numerical simulations. [source] Simultaneous Measurements of Ion Temperature by Segmented Tunnel and Katsumata ProbeCONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-7 2008J. Adámek Abstract Simultaneous measurements of the ion temperature by the segmented tunnel and Katsumata probe in the CASTOR tokamak are reported. The segmented tunnel probe measures two ion saturation currents Iseg 1, Iseg 2 towards two segments of the tunnel. The axis of the tunnel is aligned with the total magnetic field. The value of the ratio of these two currents combined with the results of the PIC modeling provides the ion temperature. Design and experimental arrangement of the Katsumata probe enable us to measure the pure ion current by sweeping the applied voltage. The ion temperature is then estimated from the exponential part of the measured I , V characteristic. Simultaneous measurements of the ion temperature by the segmented tunnel and Katsumata probe agree within a few eV. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Elementary Many-Particle Processes in Plasma MicrofieldsCONTRIBUTIONS TO PLASMA PHYSICS, Issue 3 2006M. Yu. Abstract The effect of electric and magnetic plasma microfields on elementary many-body processes in plasmas is considered. As detected first by Inglis and Teller in 1939, the electric microfield controls several elementary processes in plasmas as transitions, line shifts and line broadening. We concentrate here on the many-particle processes ionization, recombination, and fusion and study a wide area of plasma parameters. In the first part the state of art of investigations on microfield distributions is reviewed in brief. In the second part, various types of ionization processes are discussed with respect to the influence of electric microfields. It is demonstrated that the processes of tunnel and rescattering ionization by laser fields as well as the process of electron collisional ionization may be strongly influenced by the electric microfields in the plasma. The third part is devoted to processes of microfield action on fusion processes and the effects on three-body recombination are investigated. It is shown that there are regions of plasma densities and temperatures, where the rate of nuclear fusion is accelerated by the electric microfields. This effect may be relevant for nuclear processes in stars. Further, fusion processes in ion clusters are studied. Finally we study in this section three-body recombination effects and show that an electric microfield influences the three-body electron-ion recombination via the highly excited states. In the fourth part, the distribution of the magnetic microfield is investigated for equilibrium, nonequilibrium, and non-uniform magnetized plasmas. We show that the field distribution in a neutral point of a non-relativistic ideal equilibrium plasma is similar to the Holtsmark distribution for the electrical microfield. Relaxation processes in nonequilibrium plasmas may lead to additional microfields. We show that in turbulent plasmas the broadening of radiative electron transitions in atoms and ions, without change of the principle quantum number, may be due to the Zeeman effect and may exceed Doppler and Stark broadening as well. Further it is shown that for optical radiation the effect of depolarization of a linearly polarized laser beams propagating through a magnetized plasma may be rather strong. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Light at the end of the tunnel for the blind leading the blind?DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 2 2006Colin Kennedy No abstract is available for this article. [source] Judgment and action knowledge in speed adjustment tasks: experiments in a virtual environmentDEVELOPMENTAL SCIENCE, Issue 2 2003Susanne Huber Two experiments were conducted to investigate children's and adults' knowledge of time and speed in action and judgment tasks. Participants had to set the speed of a moving car to a new speed so that it would reach a target line at the same time as a reference car moving at a higher speed and disappearing in a tunnel at the midway point. In Experiment 1 (24 10-year-olds, 24 adults), children's and adults' speed adjustments followed the normative pattern when responses had to be graded linearly as a function of the car's initial speed. In a non-linear condition, only adults' action responses corresponded with the normative function. Simplifying the task by shortening the tunnel systematically in Experiment 2 (24 10-year-olds, 24 adults) enabled children to grade the speeds adequately in the action conditions only. Adults now produced normative response patterns in both judgment and action. Whether people show linearization biases was thus shown to depend on the interaction of age, task demands and response mode. [source] Targeting Alzheimer's disease: Is there a light at the end of the tunnel?DRUG DEVELOPMENT RESEARCH, Issue 2 2002David Gurwitz Abstract The prevalence of Alzheimer's disease (AD) is on the rise in developed nations as a consequence of longer human lifespan. Current costs to society are alarming, and are projected to become even more demanding on future health budgets. Considering the relative success of Parkinson's disease pharmacotherapy, the success of AD therapy has been disappointing. Quite a few novel and promising AD drug targets are presented in this special issue of Drug Development Research. These are built on countless research studies, by many bright minds, carried out over the last several decades. However, the answer to the growing AD threat must include reliable and accurate tools, presently lacking, for its early diagnosis in at-risk individuals. Drug Dev. Res. 56:45,48, 2002. © 2002 Wiley-Liss, Inc. [source] Improvement and validation of a snow saltation model using wind tunnel measurementsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 14 2008Andrew Clifton Abstract A Lagrangian snow saltation model has been extended for application to a wide variety of snow surfaces. Important factors of the saltation process, namely number of entrained particles, ejection angle and speed, have been parameterized from data in the literature. The model can now be run using simple descriptors of weather and snow conditions, such as wind, ambient pressure and temperature, snow particle sizes and surface density. Sensitivity of the total mass flux to the new parameterizations is small. However, the model refinements also allow concentration and mass flux profiles to be calculated, for comparison with measurements. Sensitivity of the profiles to the new parameterizations is considerable. Model results have then been compared with a complete set of drifting snow data from our cold wind tunnel. Simulation mass flux results agree with wind tunnel data to within the bounds of measurement uncertainty. Simulated particle sizes at 50 mm above the surface are generally larger than seen in the tunnel, probably as the model only describes particles in saltation, while additional smaller particles may be present in the wind tunnel at this height because of suspension. However, the smaller particles carry little mass, and so the impact on the mass flux is low. The use of simple input data, and parameterization of the saltation process, allows the model to be used predictively. This could include applications from avalanche warning to glacier mass balance. Copyright © 2008 John Wiley & Sons, Ltd. [source] Experimental determination of saltating glass particle dispersion in a turbulent boundary layerEARTH SURFACE PROCESSES AND LANDFORMS, Issue 14 2006H. T. Wang Abstract A horizontal saltation layer of glass particles in air is investigated experimentally over a flat bed and also over a triangular ridge in a wind tunnel. Particle concentrations are measured by light scattering diffusion (LSD) and digital image processing, and velocities using particle image velocimetry (PIV). All the statistical moments of the particle concentration are determined such as mean concentration, root mean square concentration fluctuations, skewness and flatness coefficients. Over the flat bed, it is confirmed that the mean concentration decreases exponentially with height, the mean dispersion height being a significant length scale. It is shown that the concentration distribution follows quite well a lognormal distribution. Over the ridge, measurements were made at the top of the ridge and in the cavity region and are compared with measurements without the ridge. On the hill crest, particles are retarded, the saltation layer decreases in thickness and concentration is increased. Downwind of the ridge, particle flow behaves like a jet, in particular no particle return flow is observed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Impact of a rock avalanche on a moraine-dammed proglacial lake: Laguna Safuna Alta, Cordillera Blanca, PeruEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2005Bryn Hubbard Abstract Moraines that dam proglacial lakes pose an increasing hazard to communities in the Andes and other mountain ranges. The moraines are prone to failure through collapse, overtopping by lake waters or the effect of displacement waves resulting from ice and rock avalanches. Resulting floods have led to the loss of thousands of lives in the Cordillera Blanca mountains of Peru alone in the last 100 years. On 22 April 2002 a rock avalanche occurred immediately to the south-west of Laguna Safuna Alta, in the Cordillera Blanca. The geomorphic evidence for the nature, magnitude and consequences of this event was investigated in August 2002. Field mapping indicated that the avalanche deposited 8,20 × 106 m3 of rock into the lake and onto the surface of the frontal region of Glaciar Pucajirca, which flows into the lake. Repeated bathymetric surveying indicated that ,5 × 106 m3 of this material was deposited directly into the lake. The immediate effect of this event was to create a displacement wave that gained in height as it travelled along the lake basin, overtopping the impounding moraine at the lake's northern end. To achieve overtopping, the maximum wave height must have been greater than 100 m. This, and subsequent seiche waves, caused extensive erosion of both the proximal and distal faces of the impounding terminal moraine. Further deep gullying of the distal face of this moraine resulted from the supply of pressurized water to the face via a relief overflow tunnel constructed in 1978. Two-dimensional, steady-state analysis of the stability of the post-avalanche moraine rampart indicates that its proximal face remains susceptible to major large-scale rotational failure. Copyright © 2005 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||