Artikeldatenbank
Autor(en) | Titel | Zeitschrift | Ausgabe | Seite | Rubrik |
---|---|---|---|---|---|
Current masonry topics at the third Poroton masonry convention / Aktuelle Mauerwerksthemen beim 3. Poroton-Mauerwerkskongress | Mauerwerk | 3/2015 | 239-240 | Veranstaltungen | |
Exenberger, Hans; Massimo-Kaiser, Ines Maria; Flora, Matthias | Current developments of digital ground modelling in tunnelling | Geomechanics and Tunnelling | 3/2022 | 284-289 | Topics |
KurzfassungThis article analyses and discusses the current state of the art in the development of digital ground models in tunnelling. Following a review and discussion of the literature research combined with interview responses, a deficit analysis was performed. It shows why current projects mainly work with models and software that function as isolated solutions. A lack of software developments and limited collaborative work mean that the effects of current findings cannot immediately be implemented in models. Accordingly, the enormous potential of full coaction can only be imagined. A further problem is the lack of loss-free data exchange across varying project phases and participants. Science is already moving in the right direction with the goal of harmonising the basic systematics. Finally, requirements for a digital ground model are formulated, and in combination with collaborative working and improved communication, these result in a large number of advanced possible applications. x | |||||
Zehfuß, Jochen; Mittmann, Thorsten | Current developments in fire protection - Changeover to design and classification according to the Eurocode / Aktuelle Entwicklungen im Brandschutz - Umstellung auf die Bemessung und Klassifizierung nach europäischen Normen | Mauerwerk | 1/2016 | 49-63 | Fachthemen |
KurzfassungThe European requirements for fire safety design and testing of structural masonry members are already the governing requirements in many cases. In principle, both the European and the German classification may be used according to the Bauregelliste. However, the latter may only be used when European classification of a member or construction material is not possible because the appropriate European standards do not exist. The European standards do not differ fundamentally from the German standard DIN 4102-2. One significant difference is that according to the DIN 4102-2, it was required to carry out two tests with the most unfavourable result governing, while according to the European standard, only one test is required. According to the EN Standard, the tests for fire resistance and the reaction to fire are carried out separately. There are other differences related to the pressure in the furnace as well as the use of plate thermocouples instead of jacketed thermocouples. Fire safety design of masonry is carried out in accordance with EC 6-1-2 and the National Annex. Only the members not regulated in the EC 6-1-2, e.g. pre-cast masonry members, non-load-bearing walls, lintels, connections and joints, should be designed and checked according to the revised DIN 4102-4. x | |||||
Dietzel, Martin; Purgstaller, Bettina; Leis, Albrecht; Reichl, Peter; Stadler, Hermann; Niedermayr, Andrea; Rinder, Thomas; Wagner, Hanns | Current challenges for scaling of tunnel drainage systems - Modelling approaches, monitoring tools and prevention strategies / Aktuelle Herausforderungen bei der Versinterung von Tunneldränagen - Modellierungsansätze, Monitoringwerkzeuge und Präventionsstrategien | Geomechanics and Tunnelling | 6/2013 | 743-753 | Topics |
KurzfassungScaling of tunnel drainage systems comprises complex reaction mechanisms, which are essentially caused by the interaction of water with cement-based materials and the atmosphere. The resulting precipitation of CaCO3 in the drainage is an economically highly challenging task for tunnel operators with respect to maintenance and cleaning action. Hydrochemical modelling is used to decipher reaction mechanisms and thus to provide quantifications, which are required to develop monitoring tools, like in-situ alert systems, and prevention strategies, like application of low-eluting shotcrete and inhibitors. x | |||||
CUB - Fachmesse für den computerunterstützten Bauprozeß | Bautechnik | 1/2003 | 66 | Termine | |
CTRL-Tunnelbauwerke - TBM-Vortriebe beendet | Bautechnik | 12/2004 | 996-998 | Berichte | |
CSC im Internet | Bautechnik | 1/2000 | 89 | Nachrichten | |
Crude steel production in June 2011 | Steel Construction | 3/2011 | 149 | News | |
Dulake, Chris | Crossrail - design and construction / Crossrail - Entwurf, Bemessung und Ausführung | Geomechanics and Tunnelling | 5/2011 | 592-604 | Topics |
KurzfassungCrossrail is a new railway currently being constructed in London and is the largest construction project in Europe. Linking existing surface railways to the east and west of the capital via 21 km of new twin bore tunnels it will run 118 km from end to end. This paper briefly summarises the benefits of the scheme and its sustainability strategy and goes on to describe the design of the sprayed concrete and bored tunnels, management and mitigation of ground movements. It finishes by outlining the contractual framework for the procurement of the main construction contracts. x | |||||
Berthellemy, Jacques; Schavits, David; Erre, Charlotte | Crossing motorways under traffic without intermediate piers | Steel Construction | 3/2016 | 200-206 | Articles |
KurzfassungThe European research programme SBRI attempted to reveal the costs caused during the service life of a bridge - direct costs for the bridge owner as well as indirect costs for users. The principal results of SBRI should make it possible to take better account of the true costs of a central pier by considering the risks in the construction phase and those that may threaten the highway overpass during its service life. x | |||||
Knobloch, Markus; Pauli, Jacqueline; Somaini, Diego; Frangi, Andrea | Cross-sectional capacity and flexural buckling resistance under fire conditions - An experimental study | Stahlbau | 9/2014 | 657-667 | Fachthemen |
KurzfassungThis paper presents an experimental study on the cross-sectional capacity and flexural buckling resistance under fire conditions. Steady state stub and slender column tests were carried out at ambient and elevated temperatures on square and rectangular hollow sections as well as H-sections. In addition, transient state slender column tests were performed on H-section test specimens. The compressive load was applied centrically or eccentrically to the test specimens. The paper presents the testing programme, the geometry of the test specimens including initial geometrical imperfection measurements, elevated temperature material properties, test setup, the execution and the results of the stub and slender column tests. x | |||||
Cross-sectional behaviour and design of ferritic and duplex stainless steel EHS in compression | Stahlbau | 2/2022 | 121 | Empfehlungen der Redaktion | |
Mohammed, Asif; Cashell, Katherine A. | Cross-sectional behaviour and design of ferritic and duplex stainless steel EHS in compression | Steel Construction | 4/2021 | 279-287 | Articles |
KurzfassungThis paper describes an investigation into the cross-sectional behaviour of elliptical hollow section (EHS) columns made from ferritic and duplex stainless steel. The EHS is a relatively new structural shape with a number of favourable attributes including aesthetic appeal, high strength-to-weight ratio, good torsional resistance and excellent flexural strength. In recent years there have been significant developments in the analysis and understanding of these shapes, although most studies have focused on carbon steel EHS. The work so far is taken a step further here by considering some of the newer grades of stainless steel that are used in structural applications. A numerical model is developed and validated against test data from the literature and is then employed to generate structural performance data. Subsequently, parametric studies are performed to investigate the influence of individual parameters such as the material properties, aspect ratio and local slenderness of cross-sectional elements. The accuracy of existing design procedures is assessed by comparing the numerical data with the resistances obtained using Eurocode 3. It is shown that the cross-sectional slenderness limits given in Eurocode 3 for EHS members made from carbon steel can also be safely used for sections made from ferritic and duplex stainless steel. x | |||||
Strauss, Armin; Papakonstantinou, Spyridon | Cross passages in soil - ground freezing, segment application, excavation and displacement monitoring for segmental lining / Querschlagherstellung im Lockermaterial - Vereisung, Tübbingsicherung, Vortrieb und Deformationsauswertung für die Tübbingschale | Geomechanics and Tunnelling | 5/2013 | 494-499 | Topics |
KurzfassungAfter more than 30 years of planning, construction of the Biel East city bypass started on 3 December 2007. The biggest challenge of this project was tunnel excavation in a zone of soil-like material with a length of 2 × 1,000 m, with extremely heterogeneous and variable geological conditions. The main tunnels were excavated by an earth pressure balance machine (diameter 12.56 m), and the cross passages (every 300 m) were constructed by conventional tunnelling methods with shotcrete support. In zones where fully saturated sands prevail (“Alte Schwemmsande”), brine ground freezing techniques were used. In order to prevent overloading of the main tunnels due to freezing pressures, these were supported by a combination of steel frames and dowel pins. Back analyses based on measured displacements of the segmental lining led to the conclusion that freezing pressures did not develop to the extent anticipated under the given ground conditions. x | |||||
Schubert, Peter; Moritz, Bernd | Cross passages for segmental lined tunnels - structural analysis, test results and practical solutions / Querschläge bei Tübbingauskleidungen - statische Untersuchungen, Versuche und praktische Lösungen | Geomechanics and Tunnelling | 1/2019 | 2-3 | Editorials |
Cross passages for segment-lined tunnels | Geomechanics and Tunnelling | 1/2019 | Cover Pictures | ||
KurzfassungThe squeezed connection developed by DSI Underground for a fast and safe connection of pipe umbrellas is a decisive step in the development history of the AT-Pipe Umbrella System. The system ensures a simple, fast and cost-efficient connection of pipe umbrella tubes. The squeezed connection results in increased bending stiffness in the connection area in comparison to conventional threaded tubes. Furthermore, the load-bearing capacity of the connection is more than 50 % higher than the elastic design value of default pipe umbrella tubes (see page 96). x | |||||
Iasiello, Cosimo; Torralbo, Juan Carlos Guerra; Pérez Caldentey, P.E. Alejandro | Cross passages between TBM tunnels: The experience in Spanish high-speed railway tunnels | Geomechanics and Tunnelling | 1/2019 | 62-68 | Topics |
KurzfassungThis paper describes, by means of two practical examples, the different approaches employed to design and build cross passages between segmental lined tunnels for high speed railway lines in Spain. The increment of principal stresses at the cross passages leads to the need of an additional support system for the tunnel lining. The chosen solution for this support system depends mainly on the ground conditions, the tunnel overburden and contractor's local experience. The first example is related to the Pajares Tunnels bored in the San Emiliano formation and the second one collects the experiences of the Guadarrama tunnels bored in very hard gneiss and granite rocks. The aim of this paper is to establish some key aspects to be considered when choosing the cross passage design and the corresponding excavation process. x | |||||
Yang, Yuguang; den Uijl, Joop; Walraven, Joost | Critical shear displacement theory: on the way to extending the scope of shear design and assessment for members without shear reinforcement | Structural Concrete | 5/2016 | 790-798 | Technical Papers |
KurzfassungThis paper presents a new theory for the shear capacity of reinforced concrete members without shear reinforcement. While recognizing that there are multiple failure mechanisms, the theory attributes the opening of a critical flexural shear crack as the lower bound of the shear capacity. It proposes that the shear displacement of an existing flexural crack can be used as the criterion for the unstable opening of the critical flexural shear crack. Based on the theory, the paper presents a simplified shear evaluation model. Compared with the current shear provisions in the design codes, the model is characterized by good accuracy and a solid physical background. It demonstrates a great flexibility for dealing with complex design conditions. As an example, the paper discusses the possibility of extending the theory to the shear resistance of higher-strength concrete. The suggested method provides a more logical and fluent transition from normal- to high-strength concrete and shows good agreement with experimental observations. x | |||||
Moritz, Bernd; Wagner, Hanns; Mussger, Klaus; Handke, Dieter; Harer, Gerhard | Criteria for the selection of tunnelling method through the example of the Koralm Tunnel / Kriterien zur Wahl der Vortriebsarten am Beispiel des Koralmtunnels | Geomechanics and Tunnelling | 4/2011 | 305-316 | Topics |
KurzfassungWith a length of 32.9 km, the Koralm tunnel is the key structure on the route of the new 130 km Koralm railway between Graz and Klagenfurt (Austria). This paper defines the most important boundary conditions for dividing the sections and for selecting the methods of tunnelling (sequential or continuous). The focus of the article is mainly on section KAT 3, in which both tertiary sediments and crystalline rock sequences, including the Lavanttal fault zone, are excavated by sequential and continuous tunnelling. The considerations for this section also include the decision to excavate the sediments and the Lavanttal fault zone using a shield machine with earth pressure components. The criteria for defining the different operating modes are described. x | |||||
John, Max; Pilser, Gerhard | Criteria for selecting a tunnelling method using the first and the second tube of the Pfänder tunnel as example / Kriterien zur Wahl der Vortriebsmethode am Beispiel Pfändertunnel erste und zweite Röhre | Geomechanics and Tunnelling | 5/2011 | 527-533 | Topics |
KurzfassungFor the construction of the first tube of the Pfänder Tunnel, a pilot tunnel was excavated in 1974/1975 in advance of the main tunnel using two open TBMs. As a result of the positive experiences made with the pilot tunnel, the tenders for the excavation of the first tube included both a NATM advance and a TBM advance with open TBM. On the basis of the offers obtained, the first tube was constructed between 1977 and 1979, using the NATM. x | |||||
CRH Clay Solutions GmbH vertreibt A·K·A Markenprodukte | Mauerwerk | 5/2009 | 299 | Firmen und Verbände | |
Marte, Roman; Hofmann, Robert | Creeping large-scale landslides - Characterisation and assessment of safety / Kriechförmig verlaufende Großmassenbewegungen - Charakterisierung und Bewertungen des Sicherheitszustands | Geomechanics and Tunnelling | 1/2020 | 32-51 | Topics |
KurzfassungThis article investigates to what extent a “condition and safety assessment” with a classically defined safety factor &eegr; (now partial safety factor or load factor) is useful or indeed possible for creeping slides of large masses as are often encountered in the Alps, or whether different quantities like the displacement rate and its change with time are more useful for the description of the condition of such large-scale slides. This discussion is held under the viewpoint that various procedures with different results are available for the determination of such a “safety factor” and consequently there are also justified discrepancies between experts in the assessment of such a “safety factor for the current state” of the moving slope. The authors are of the opinion that the partial safety factors required by standards or former “safety factors” are predominantly intended for engineering structures, earthworks and dams but not generally for creeping slopes. In this case, classification of creep rate and the geological engineering assessment are always preferred. This is illustrated with two examples. x | |||||
Hofmann, Robert; Sausgruber, Johann Thomas | Creep behaviour and remediation concept for a deep-seated landslide, Navistal, Tyrol, Austria / Kriechverhalten und Sanierungskonzept einer Großhangbewegung, Navistal, Tirol, Österreich | Geomechanics and Tunnelling | 1/2017 | 59-73 | Topics |
KurzfassungIn the valley of Navis, the village of Kerschbaum with 84 houses stands on a slowly downhill moving, relatively corase grained, aqua bearing earth-flow/-slide about 40 m thick. This secondary movement overlies a deep-seated rock slide. The rates of movement at the surface of the earth-flow/-slide were between 1 und 3 cm/a before the implementation of remedial works. Starting from the geotechnical and geomechanical model of the slope, measures were developed, which were intended to reduce the movement. A monitoring system was installed to provide information about the movement and slope water conditions of the earth-flow/-slide and the sliding rock mass. In order to estimate the creep behaviour of the earth-flow/-slide, the ductility index ILZR was determined from shear tests. A simple flow law was assumed for the estimation of the change of creep rate. Measurements over a period of about 18 months after the first phase of remedial works show rates between 0.5 and 1.2 cm/a. The reduction of the rate of movement is compared with the creep model applied and the viscosity index ILZR to check the validity. x | |||||
Groli, Giancarlo; Pérez Caldentey, Alejandro; Soto, Alejandro Giraldo | Cracking performance of SCC reinforced with recycled fibres - an experimental study | Structural Concrete | 2/2014 | 136-153 | Technical Papers |
KurzfassungThis paper presents an experimental campaign aiming to assess the cracking behaviour of flexural members made with self-compacting concrete (SCC) and reinforced with both rebars and steel fibres recycled from end-of-life tyres (ELT). The characteristics, constructability and performance of this new type of fibre are first discussed. The results of the tests carried out are then presented and discussed. The parameters that have been investigated are: &phgr;/&rgr;s,ef, concrete cover and fibre content. The results obtained show improvement in cracking behaviour, especially for low reinforcement ratios and large covers. Results are compared with the predictions of the recently published fib Model Code for Concrete Structures 2010. The main objective of this investigation is to evaluate the efficiency of a new type of fibre technology for crack width control of RC elements, with advantages in sustainability from the point of view of recycling and durability. x | |||||
Pérez Caldentey, Alejandro; Corres Peiretti, Hugo; Peset Iribarren, Joan; Giraldo Soto, Alejandro | Cracking of RC members revisited: influence of cover, &phgr;/&rgr;s, ef and stirrup spacing - an experimental and theoretical study | Structural Concrete | 1/2013 | 69-78 | Article |
KurzfassungThis article describes an experimental programme aimed at studying the effect of cover, ratio between diameter and effective reinforcement ratio (&phgr;/&rgr;s, ef) and the influence of stirrup spacing on the cracking behaviour of reinforced concrete elements. The experimental programme was conceived in order to contribute to the debate - fuelled by the publication in recent years of Eurocode 2 EN1992-1-1 and the revision of the Model Code under way when the tests were carried out (and now published as a finalized document) - regarding the influence of these parameters on cracking. Important theoretical aspects are discussed, including where the crack width is estimated by current code formulations and what relevance this may have on the correlation between crack opening and durability of RC structures, especially with regard to structures with large covers. The effect of stirrup spacing, a variable absent from current codes, is also discussed. x |