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Hrkac T.,Regional Municipality of York | Urschitz G.J.,STRABAG AG
Underground - The Way to the Future: Proceedings of the World Tunnel Congress, WTC 2013 | Year: 2013

The Southeast Collector Project consists of the construction of 15-km of gravity trunk sewer, 16 shafts and six related facilities within the Greater Toronto Area (GTA), Canada. The total project cost is estimated at $550 million (CAD). The tunnel will be constructed using four owner supplied 3.62 metre diameter EPB TBMs. The project design and local geology have introduced several unique challenges. This paper provides an overview of the project and explores some of those challenges. Read how a Segment Handling Device helped mitigate the schedule impacts associated with a requirement to have the two longest tunnel drives mine in orthogonal directions from a 51 metre deep shaft. Discover a unique approach to rotating an EPB TBM within a 14 metre diameter shaft. Learn how a combination of soil replacement and vertical ground freezing helped resolve challenges related to constructing a critical maintenance shaft. And find out how the logistical challenge of managing 16 pre-determined access compounds spread over 15-km, was overcome. Such innovative approaches were necessary to maintain the critical completion schedule and to avoid extensive delays to the project. © 2013 Taylor & Francis Group.

The Rohtang Tunnel has been advancing into the Himalaya Mountains in the northern state of Himachal Pradesh since autumn 2010. After the completion of almost 50 % of the alignment, it is time for an intermediate report. The article will intentionally not only describe technical matters but also describe the local aspects of tunnelling in India. © 2014 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.

Urban S.,Strabag AG | Strauss A.,University of Vienna | MacHo W.,University of Vienna | Bergmeister K.,University of Vienna | And 2 more authors.
Bautechnik | Year: 2012

Concrete structures under cyclic loading - robustness and redundancy considerations for residual lifetime optimization Concerning fatigue analysis of concrete structures, especially in offshore areas, the continuous degradation of material parameters is not taken into account. One effect of the damaged material structure in parts of the concrete cross section is the stress redistribution from highly loaded (damaged) areas to low loaded (undamaged) areas and therefore an elongation of the theoretical residual service life. Concrete is described by the use of material parameters. A very important parameter is the E-modulus, also called the modulus of elasticity. A possibility to consider the degradation process within the material concrete is the gradual adaption and minimization of the E-modulus. In order to analyze and dimension a structure, to predict the internal stress distribution and deflection behavior, it is very important to specify this parameter and to know the variation according loading history and time. In addition to robustness and redundancy definition given in this article, a life time calculation of the Strabag gravity base test foundation in Cuxhaven according Model Code 1990 for the planned fatigue tests with realistic reduction of E-Modulus is performed. Concerning the case study "Cuxhaven" the use of system robustness in order to extend the residual service life is been demonstrated by means of a linear iterative modeling process. Copyright © 2012 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.

Engineering structures are subjected to continuous and increasing static and dynamic loads from artificial and natural environmental conditions (e.g. wind, traffic loads or wave loading on offshore wind turbine structures). Dynamic Loads can result in fatigue phenomena within the material concrete which are not totally explored even in their beginnings. Especially in the fields of Foundations for wind energy plants on- and offshore fatigue is a big problem. The Fatigue associated load combinations are mostly the decisive ones for design and dimensioning of the structure. The targets of the research are the development of a monitoring system for detecting the initiation or the early stage of a fatigue process in concrete and for the identification of the degree of deterioration in the concrete structure. The full scale model of a new type of gravity base foundation for offshore wind turbines in Cuxhaven projected by the Ed. Züblin AG is an optimal possibility to test the monitoring system within a concrete structure of real dimensions. The objective of this contribution is to provide a short review of concrete fatigue properties, to discuss, demonstrate and portray preliminary analyses results which are decisive for the final fatigue test layout at the Strabag gravity base foundation in Cuxhaven. The conduction of the fatigue tests at the gravity base foundation are planned in the beginning of the year 2013. Copyright © 2012 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.

Avery T.,Avar Construction | Porubsky D.,Strabag AG | Leigh C.,Latin America | Martinez H.,Latin America
Proceedings - Rapid Excavation and Tunneling Conference | Year: 2015

Canopy tubes are frequently used in the Sequential Excavation Method (SEM) to provide stability in bad ground ahead of a portal or tunnel face. Canopy tubes or umbrella tubes are a support element consisting of a series of small diameter pipes, ranging from 76.1 mm to 168.3 mm diameter. Two projects demonstrating the ability of canopy tubes are summarized in this paper. The first project is the Santiago Metro in Santiago, Chile, which relied heavily on canopy tubes for construction of new stations and tunnels on the new Line 6. A design methodology using canopy tubes, lattice girders and shotcrete should reduce the construction time of the stations from 17 to 25 months down to 9-10 months. The second project is the expansion of the U1 subway line in Vienna, Austria where telescoping canopy tubes were used to provide support going through a diaphragm wall underneath an existing highway tunnel.

Lackner C.,Strabag AG | Lackner K.,ZT Dr. Lackner Consult
GA 2012 - 5th Asian Regional Conference on Geosynthetics: Geosynthetics for Sustainable Adaptation to Climate Change | Year: 2012

This paper presents the case study B114 Trieben-Sunk and is dealing with conventional, analytical calculation methods and numerical simulations of geosynthetic reinforced embankments. Two and threedimensional analysis are performed. For conventional calculations GGU Software is used and for numerical simulations Plaxis V.8 and Plaxis 3D Tunnel is employed. The goal is to simulate respectively to evaluate the behavior of geosynthetic reinforced embankments. The differences between conventional and numerical calculations are shown and the results are compared. An important aspect is the determination of the global safety factor and the failure mechanism. With Plaxis the deformations of the embankment and the resulting forces in geosynthetics and anchors are calculated. Variation of the ground stiffness and the road roller compaction force shows the influence on the forces in geosynthetics. The settlements of the embankment are calculated and a comparison with measurements at the project Trieben-Sunk is provided. Finally advantages and disadvantages of each, conventional and numerical method of calculation, are shown. Further the actual performance of the road under traffic is presented.

Berger J.,Vienna University of Technology | Bruschetini-Ambro S.Z.,Strabag AG | Kollegger J.,Vienna University of Technology
Structural Concrete | Year: 2011

It is proposed to build concrete bridges with tendons fully encapsulated in plastic ducts and without the use of reinforcing steel. In this case the durability of the proposed bridge depends only on the durability of the concrete because corrosion is no longer a determining factor regarding the lifetime of the structure. The requirements of the serviceability and ultimate limit states are fulfilled by providing post-tensioned tendons with strands fully encapsulated in plastic ducts and watertight anchorages. Since the proposed bridge does not contain any steel, which would be endangered by material-related corrosion, there is no need for insulation to the deck. Consequently, there is also no need for pavement and edge beams. This concept of building bridges represents a breakthrough with regard to sustainability and durability of concrete bridges and is applicable to small and mediumsized bridges. The method has already been implemented for the design of the Egg-Graben Bridge in the Großarl valley in the province of Salzburg, Austria. Prior to the actual construction of the bridge, large-scale tests were performed to obtain practical values for the serviceability, ductility and loadbearing capacity of this structural system. Copyright © 2011 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.

Agency: European Commission | Branch: FP7 | Program: CP-IP | Phase: EeB.NMP.2013-5 | Award Amount: 11.10M | Year: 2013

eeEmbedded will develop an open BIM-based holistic collaborative design and simulation platform, a related holistic design methodology, an energy system information model and an integrated information management framework for designing energy-efficient buildings and their optimal energetic embedding in the neighbourhood of surrounding buildings and energy systems. A new design control and monitoring system based on hierarchical key performance indicators will support the complex design collaboration process. Knowledge-based detailing templates will allow energy simulations already in the early design phase, and BIM-enabled interoperability grounded on a novel system ontology will provide for a seamless holistic design process with distributed experts, and a seamless integration of simulations in the virtual design office (energy performance, CO2, CFD, control system, energy system, climate change, user behaviour, construction, facility operation), thus extending it to a real virtual design lab. A test period of 12 project months, overlapping the first 42 development months of the project, will provide for real pre-market validation of the system on two real embedded buildings of different types, namely (1) residential or office, and (2) hospital buildings. The development work will be soundly based on 2 business models the business model of the owners and hence the equipment providers and the business model of construction and design companies, and on a set of ISO and industry standard data structures and specifications such as IFC, STEP, CityGML and OWL. A new ontology-based Link Model will provide the bridge between the multiple physical and mathematical models involved in the eeBuilding domain warranting the desired data and services interoperability.

Lackner C.,STRABAG AG | Bergado D.T.,Asian Institute of Technology | Semprich S.,Graz University of Technology
Geotextiles and Geomembranes | Year: 2013

This paper presents experimental investigations on an innovative construction method for reinforced soil structures by geosynthetics called prestressed reinforced soil. The concept of prestressed reinforced soil, (PRSi) developed to increase the bearing capacity of a reinforced soil structure and to improve its displacement behaviour is introduced. The concept of PRSi is validated by experimental studies. Large scale experimental tests conducted at the Institute of Soil Mechanics and Foundation Engineering at Graz University of Technology, Austria and their results are presented. Over 60 path-controlled static load displacement tests have been performed to investigate the load displacement behaviour of 10 different reinforced soil structures. The reinforced soil structures have been constructed under homogeneous laboratory conditions with respect to construction sequence, compaction, temperature and measurement equipment to assure high quality reproducible test results. The overall results show a considerable improvement of the macroscopic load displacement behaviour of the soil structure by utilizing the concept of prestressed reinforced soil. In addition 80 cyclic load displacement tests have been conducted in Weimar, Germany to validate the concept of PRSi under cyclic loading conditions. A soil element, theoretically taken out of a reinforced soil structure, is used to investigate its behaviour under vertical cyclic load and horizontal support conditions. The macroscopic research shows that displacements occurring under cyclic loading can be reduced tremendously by installing a geogrid with the concept of PRSi. Besides investigating the macroscopic load displacement behaviour of the reinforced soil structure a detailed mesoscopic analysis using the Particle Image Velocimetry (PIV) method has been performed. From the PIV analysis it was demonstrated that the vertical and horizontal displacements under cyclic loading and below the geogrid layer decreased rapidly. © 2013 Elsevier Ltd.

Strabag Ag | Date: 2012-09-05

An air introduction nozzle for high pressure-ventilated spaces has a substantially low-cylindrical structure and a centrally located air inlet space with a cylinder shell, which is provided with openings and is radially cylindrically surrounded by at least two air expansion spaces, filled with an air-permeable material. The air expansion spaces are separated from one another by cylinder shells provided with openings. The air is discharged from the nozzle through openings of the outermost cylinder shell enclosing the at least two air expansion spaces.

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