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Vienna, Austria

Herdina J.,OBB Infrastruktur Bau AG
Geomechanik und Tunnelbau | Year: 2010

Although the expert circle of NATM users has demonstrated that they are technically capable of using the NATM successfully under almost any conditions, there are repeated difficulties concerning the handling of contracts. The construction contract with flexible provisions regarding classification and the invoicing of common costs as the basis for a collaborative project implementation has been subjected to extreme stress recently by various construction companies. The expectations of the contractor concerning tendering are not identical to the tender documents currently in use in the market. The article explains the differences and proposes a way of overcoming such problems in the future. The author maintains that in his view three main points could lead to an improvement of contract implementation: The appointment of contractors only for a plausible total price, Consultants as a partner of the client and The provision of a behaviour code for NATM construction measures.© 2010 Ernst & Sohn Verlag fu7die;r Architektur und technische Wissenschaften GmbH & Co. KG, Berlin. Source

Kohler M.,OBB Infrastruktur Bau AG | Maidl U.,Mtc Maidl Tunnelconsultants GmbH and Co. KG | Scholz M.,Ingenieurburo Muller und Hereth | Wendl K.,ILF Beratende Ingenieure ZT GmbH
Geomechanik und Tunnelbau | Year: 2012

Two tunnels were driven in the Lower Inn valley in the years 2007 to 2009 using almost identical mixshields (Ø 13.03 m) under difficult geotechnical conditions. The tunnelling works were monitored and recorded permanently in real time, from which information can be gained about the system of shield machine and surrounding ground. The documentation of the ground conditions was undertaken by geologists working for the client. The continuous documentation of tunnelling included reporting on the excavated material as the drive was underway and the documentation of face conditions during compressed air interruptions. The combination of recorded machine data and the geological documentation of the tunnel drive provides an extensive data basis, whose evaluation shows the complex relationships of the various tunnelling parameters. © 2012 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin. Source

Gehwolf P.,University of Leoben | Walter A.,Viglconsult ZT | Galler R.,University of Leoben | Wagner H.,OBB Infrastruktur Bau AG
Geomechanik und Tunnelbau | Year: 2016

For the driving of cross passages in mechanized tunnelling, different systems can be used for load transfer at the cross passage opening. With thin segmental linings, achieving high load-bearing capacity of the precast lining and the load transfer elements used pose a great challenge. For the selection of a system, not only the required support measures but also practical construction aspects such as the integration of the load transfer elements into the precast element and the installation of the elements play an important role. The use of shear dowels as a connection and load transfer element between segment rings in the cross passageoffers new possibilities in mechanized tunnelling. Particularly in connection with thin segmental linings, flexible systems of plastic with integrated steel core make it possible to resist loads with large deformations, both in the radial and longitudinal directions. In order to investigate the system behaviour of the overall system of segmental lining with thin construction and plastic shear dowels, shear tests were performed at the Chair for Subsurface Engineering of the Montanuniversität Leoben with a dowel system as the connecting element between segments. The objective of the research project initiated by the ÖBB-Infrastruktur AG is to determine the effects of different reinforcement concepts on the load-bearing capacity of the connection system. Ways of determining the failure of the construction element based on crack detection are also described. Für das Anfahren von Querschlägen im maschinellen Tunnelbau kommen unterschiedliche Systeme für die Lastabtragung im Bereich der Querschlagsöffnung zum Einsatz. Bei schlanken Tübbingauskleidungen stellt das Erzielen einer hohen Lastkapazität der Fertigteilauskleidung sowie der eingesetzten Lastabtragungselemente eine hohe Herausforderung dar. Bei der Auswahl der Systeme spielen neben den erforderlichen Sicherungsmaßnahmen die baupraktischen Aspekte wie das Integrieren der Lastabtragungselemente in das Fertigteilsegment und die Installation der Elemente eine wesentliche Rolle. Durch Verwendung von Scherdübeln als Verbindung- und Lastübertragungselement zwischen Tübbingringen im Querschlagsbereich ergeben sich neue Möglichkeiten im maschinellen Tunnelvortrieb. Insbesondere im Zusammenhang mit schlanken Tübbingauskleidungen bieten flexible Systeme aus Kunststoff mit integriertem Stahlkern die Möglichkeit, Lasten mit großen Verformungen sowohl in Radial- als auch in Längsrichtung zu übertragen. Um das Systemverhalten des Gesamtsystems zwischen Tübbingauskleidung mit schlanker Bauteildicke und Kunststoffscherdübel zu untersuchen, wurden am Lehrstuhl für Subsurface Engineering der Montanuniversität Leoben Scherversuche mit einem Dübelsystem als Verbindungselement von Tübbingen durchgeführt. Ziel des von der ÖBB-Infrastruktur AG initiierten Forschungsprojekts ist es, die Auswirkungen unterschiedlicher Bewehrungskonzepte auf die Tragfähigkeit des Verbindungssystems zu bestimmen. Ergänzend werden Möglichkeiten zur Bestimmung des Bauteilversagens auf Basis der Risserkennung aufgezeigt. © 2016 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin Source

La Poutre D.,BERNARD Ingenieure ZT GmbH | Vill M.,OBB Infrastruktur Bau AG | Immig R.,BERNARD Ingenieure ZT GmbH
Structural Stability Research Council - Annual Stability Conference, SSRC 2010 - Proceedings | Year: 2010

This paper sets out to investigate the spatial stability of twin free standing arches of a road bridge recently under construction. The bridge is located in the southern part of Austria crossing a branch line of the newly built Koralm high speed railway line from the city of Graz to the city of Klagenfurt. The bridge is composed of concrete cantilevering abutments, a composite deck and steel circular arches with tubular cross section. The arches are arranged in a basket handle scheme, spanning 30 m and the bridge deck is suspended from them by means of twin hangers consisting of round steel bars. This paper focuses on the stability design according to Eurocode 3 of the steel arches. The critical elastic buckling loads (eigenvalue) of the entire system (including abutments) is determined numerically and the plastic strength is determined for the arches only with a separate FE-Model. Finally full non-linear FE-analyses are carried out to determine the actual ultimate load. In conclusion, the suitability of the design after Eurocode 3 is determined. Source

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