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This paper presents an overview of the contents of 2nd Generation Eurocode 7 Part 2, highlighting two of the major changes introduced, being the Ground Model and the Rock Engineering implementation. The document is organized from a ground property perspective so that the role of Part 2 and the links with the geotechnical design are much clearer than in the previous edition. Its new title is a clear indication of this idea: "Ground properties" including both soil and rock properties. The need to have representative values for the ground properties is the objective of this new Part 2, which is intended to guide designers on the path to obtain those values by means of the Desk Study, Site Inspection, Field Investigation and Laboratory Testing. Given this framework, the paper explains the concepts behind the Ground Model, the main output of the Ground Investigation, which includes the ground profile, the geometric properties of the ground and its layers, groundwater, and the derived values of the ground properties, paying attention of the role of discontinuities in such ground profile. The tasks that form the Ground Investigation and the minimum number of activities to be performed are described. This new version of EN 1997 will include a Rock Engineering perspective for all above items. And finally, the ground properties of the rock material and the rock mass are listed and discussed. [ABSTRACT FROM AUTHOR]

The current first generation of Eurocodes is a suite of ten European standards for the design of buildings and civil engineering works, whose implementation started in 2010. EN 1990 sets the basis of structural design, with the other Eurocodes dealing with different materials and specific aspects of design. Geotechnical aspects of design are covered by EN 1997 "Geotechnical design", usually called Eurocode 7. The evolution of the Eurocodes started in 2012 and the main objectives of their revision were to incorporate improvements that reflect the state‐of‐the‐art in engineering design and the needs of the civil engineering market, to improve the ease‐of‐use and to harmonize practice between countries. While the original version was developed largely based on soil mechanics, the aim was that the revised version treats soil and rock on an equal basis. The second generation of the Eurocodes is now nearly finished, and the revised EN 1997 is expected to be formally approved in 2024. This paper is the first of a set of six informative papers on the revised Eurocodes and rock engineering, prepared by members of the Rock Engineering Platform of CEN/TC250/SC7, a group of rock engineering experts that has been assisting in drafting EN 1997 from a rock‐engineering perspective. The paper presents the main changes to EN 1990 and EN 1997 as far as they affect geotechnical and rock engineering design. [ABSTRACT FROM AUTHOR]

Projects Tunnel construction work in the BBT Eisack underpass construction lot completed / Tunnelbauarbeiten im BBT‐Baulos Eisackunterquerung abgeschlossen Planning process for Frankfurt Inter‐city railway tunnel shortened / Planungsprozess für Fernbahntunnel Frankfurt beschleunigt Operational exercises before commissioning of the Koralm Railway / Einsatzübungen vor Inbetriebnahme der Koralmbahn Limberg 3 – Heavy transport in the mountain / Limberg 3 – Schwertransporte im Berg Second underground lot awarded for Hamburg U5 / Zweites U‐Bahnlos für Hamburger U5 vergeben Ligerz tunnel contract awarded as part of the Ligerz‐Twann double‐track extension project / Tunnel Ligerz im Rahmen des Doppelspurausbaus Ligerz‐Twann vergeben Max Bögl commissioned to produce and deliver segments for the Brenner Base Tunnel / Max Bögl mit Produktion und Lieferung von Tübbingen für den Brenner Basistunnel beauftragt Final breakthrough for the Silvertown Tunnel / Finaler Durchbruch für den Silvertown‐Tunnel STRABAG UK opens precast tunnel segment plant in Hartlepool / STRABAG UK eröffnet Fertigteilwerk für Tunnelsegmente in Hartlepool Extensive diaphragm wall work for Jakarta metro station / Umfangreiche Schlitzwandarbeiten für U‐Bahnstation in Jakarta Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

The current Eurocode revision process is sought to improve Eurocode 7 for application to rock engineering, while including only techniques and procedures that are in widespread customary use. The revision process has exposed much about the application of the Eurocodes to rock engineering, thereby offering hints as to what material should be included in the next revision – tentatively suggested for publication in 2035. Crucially, ideas have developed about how rock engineering practice may need to develop to embrace the principles on which the Eurocodes are based. In particular, aspects of determining the properties of rock masses, and design verification by observational methods, partial factors, numerical modelling, and prescriptive rules are all thought to require significant improvement or dramatic modification. This paper highlights challenges identified regarding the application of the Eurocodes to rock engineering, and which will need to be addressed in the future. Ideas are presented about how these challenges may be overcome, but these are given in the spirit of stimulating ongoing conversation within the rock mechanics and rock engineering community rather than presenting definite proposals. [ABSTRACT FROM AUTHOR]

In 2025 the new generation of the Eurocode 7 will be introduced and set a framework for geotechnical design for the next 20 years. As Eurocode 7 is an essential design code, the changes will affect numerous practising geotechnical Engineers. The paper provides an overview of significant changes in rock engineering design introduced in the new EN 1997 part 3, considering limit state design, durability, reliability, testing and other crucial design aspects. It focuses on the anchor clause revision and first introduced design rules for rock bolts and soil‐nailed structures. The improvements described include distinguishing between different tension supporting elements that have often been confused. Furthermore, the provisions for groundwater control measures influencing the working condition and limit states for all other geotechnical systems that have not yet been comprehensively addressed in the current Eurocode 7 are also clarified. Finally, the design of the described geotechnical structure will also be strongly affected by changes in the overall philosophy of the Eurocodes, which is also explained. [ABSTRACT FROM AUTHOR]

The second generation of Eurocode 7 includes both soil and rock. In addition to the current practice of ground engineering, this document aims at incorporating rock engineering, improving the ease of use, the harmonization of regulations and covering new developments. This paper provides an overview of some of the significant changes to Eurocode 7 in rock engineering design, taking into consideration limit state design, robustness, durability, and reliability. It focuses on the design of slopes, spread foundations, and retaining structures. The clauses focus on soil mechanics, but also include special rock mechanical issues such as the influence of discontinuities and strength anisotropy on the limit states. Many matters associated to verification of rock mechanical design are linked to the use of prescriptive rules and shall be given in National Annexes. For geotechnical structures in rock, it is mentioned that geotechnical mapping and documentation is important to verify the limit states. However, the basic issues with partial factor methods for verification of the ground‐structure interaction of reinforced slopes and retaining structures are not fully resolved. This has caused some difficulties in setting up partial factors and obtaining a sufficient overview of the application of partial factor method, especially in rock engineering. The design of slopes, spread foundations and retaining structures must likewise consider other clauses in the Eurocode. Rock support for slopes and retaining structures is described in Clause 13 "Rock Bolts and Surface Support". Groundwater‐related issues are described in clause 12 "Ground water control" which influence the design and limit states for the actual geotechnical structure. Dams and levees are featured in Clause 4 "Slopes, Cuttings and Embankments". [ABSTRACT FROM AUTHOR]

The second generation of Eurocode 7 aims at covering ground, including both soil and rock. Current practice of ground engineering forms the basis, and the aim is to include rock engineering, improving ease of use, harmonization of regulations, and covering new developments. This paper deals with EN 1997 part 1 addressing the general rules of geotechnical design, connected to EN 1990, the basis of structural and geotechnical design, and parts 2 and 3 of EN 1997. The design process from ground investigation to the verification of limit states is illustrated with a focus on rock engineering. The following topics are dealt with in more detail: Geotechnical Categories: They are now based on Consequence Classes and newly introduced Geotechnical Complexity Classes. A limit state design to be sufficient has to be combined with other checks depending on these classes.Replacement of the Design Approaches of the current Eurocode 7: Ultimate limit states will be verified by a combination of Verification Cases with partial factors on actions and action effects, and sets of partial factors on ground properties and resistances, respectively.Application of numerical methods, where a ULS‐verification with two sets of partial factors is defined.Use of probabilistic methods in design by calculation, especially appropriate in cases where properties of discontinuities govern the design.Practice of the Observational Method, including design variants and regulations about their choice. [ABSTRACT FROM AUTHOR]

Projects Starting the second tunnel boring machine at the Brenner construction site Sillschlucht‐Pfons / Andrehen der zweiten Tunnelbohrmaschine am Brenner‐Baulos Sillschlucht‐Pfons Contracts for caverns and gallery system for Forbach pumped storage power station awarded / Kavernen und Stollensystem für Pumpspeicherkraftwerk Forbach beauftragt Brenner north approach: gallery construction between Schaftenau and Radfeld / Brenner‐Nordzulauf: Stollenbau zwischen Schaftenau und Radfeld First part of the Fehmarnbelt tunnel concreted / Erster Teil des Fehmarnbelt‐Tunnels betoniert EU funds Brenner Base Tunnel with another 700 million euros / EU fördert Brenner Basistunnel mit weiteren 700 Mio. Euro Four international consortia have been selected for railway equipment of the Fehmarnbelt Tunnel / Vier internationale Konsortien für bahntechnsiche Ausrüstung des Fehmarnbelt‐Tunnel ausgewählt Porr wins a major contract for the SuedLink Elbe crossing / Porr gewinnt Großauftrag für SuedLink Elbquerung Lucerne through station: preliminary project completed / Durchgangsbahnhof Luzern: Vorprojekt abgeschlossen Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Projects First tunnel boring machine goes into action at Brenner "Sill Gorge‐Pfons" / Andrehen der ersten Tunnelbohrmaschine am Brenner‐Baulos Sillschlucht‐Pfons Deutsche Bahn starts tunnelling for Wendlingen "big bend" / Deutsche Bahn startet Vortrieb für Große Wendlinger Kurve Renaturalisation of Lake Uri using tunnel spoil / Renaturierung des Urnersees mit Tunnelausbruchmaterial Contract awarded for H53 "Pfons‐Brenner" / Zuschlag für Baulos H53 Pfons‐Brenner erteilt Companies New estimate for total cost of the Brenner Base Tunnel / Neue Schätzung der Gesamtkosten für den Brenner Basistunnel Events 2nd European short course "Grouting Fundamentals & Current Practice" in Munich / Zweiter europäischer Short course "Grouting Fundamentals & Current Practice" in München Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Projects First tunnel boring machine in Brenner contract section H61 reaches destination / Erste Tunnelbohrmaschine im Brenner‐Baulos H61 am Ziel Breakthrough at Sarnersee / Durchbruch am Sarnersee Tunnel construction for the Brenner Base Tunnel North feeder / Stollenbau für den Nordzulauf zum Brenner Basistunnel beauftragt A13 Ceremony to mark start of work on the Isla Bella Tunnel / A13 Anschlagfeier Sicherheitsstollen Tunnel Isla Bella Implenia wins subway projects in Toulouse and Oslo / Implenia erhält U‐Bahnprojekte in Toulouse und Oslo Preparations for machine tunnelling in Construction Lot H41 of the Brenner Base Tunnel / Vorbereitungen für den maschinellen Vortrieb im Baulos H41 des Brenner Basistunnels Tunnel refurbishment for the Lahn Valley Railway / Tunnelsanierung für Lahntalbahn Restoration of the land to its natural state in the Eisack underpass construction lot / Renaturierungsmaßnahmen im Baulos Eisackunterquerung Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

In the construction industry, increased efforts are being made to automate production processes using industrial robots in order to increase efficiency, improve quality and optimize the use of materials. Tunnel construction is particularly suitable for the use of modern production methods, as the increased use of machines and the high repetition factor of the components used make it possible to scale production technology across project boundaries. This paper provides examples of current developments in segment production, in particular the use of industrial robots in the prefabrication of reinforcement cages and subsequent concreting. Necessary adaptations in segment design are pointed out when welded reinforcement is used, and conceivable further developments are shown. The medium‐term goal is a continuous IT‐based production control system that allows short‐term adjustments to segment production, logistics and subsequent installation in the tunnel. [ABSTRACT FROM AUTHOR]

Glacial soil deposits are present in Europe on both sides of the Alps, in Scandinavia, Northern Germany, Poland and in North America. There are typical names of the stages of the glaciation, however, the geotechnical characteristics of glacial deposits are similar in all regions; but are very heterogeneous locally. Glacial deposits extend from boulders to invisible silt particle (rock flour) and to clay particles, both of similar grain size. In this paper the focus will be on clean gravel without fines, so‐called open gravel and the challenges and solutions for tunnelling. Face support by pure bentonite slurry is insufficient in open gravel. Different techniques have been used in practice: clogging the pore channels with fines of appropriate gradation by controlling the content fines in the slurry. Use of high viscous slurry with increased clay or bentonite content. In another solution lime powder and polymers were added in the excavation chamber of an earth‐pressure shield to modify the ground. Other aspects such as muck disposal will be evaluated. [ABSTRACT FROM AUTHOR]

Projects Final major tunnelling contract awarded for Sydney Metro West / Letzter großer Tunnelbauauftrag für Sydney Metro West vergeben Implenia builds Boknafjord tunnel in Norway / Implenia baut Boknafjord‐Tunnel in Norwegen Contracts for main tunnel and materials management for second tube of Gotthard road tunnel / Verträge über Haupttunnel und Materialbewirtschaftung für zweite Röhre Gotthard Straßentunnel Greywacke – Rock of the Year 2023 / Grauwacke – Gestein des Jahres 2023 Carcassing work in the Albula Tunnel complete / Roharbeiten im Albulatunnel abgeschlossen Second tube of Long Itchington Wood Tunnel launched / Zweite Röhre der Long Itchington Wood Tunnels angefahren Shell construction of cross passages in Rastatt Tunnel complete / Querschläge im Tunnel Rastatt im Rohbau fertig Blast driving in Cholfirst safety tunnel started / Sprengvortrieb im Sicherheitsstollen Cholfirst gestartet North Portal of Brenner Base Tunnel is taking shape / Nordportal des Brenner‐Basistunnels nimmt Gestalt an New Wendlingen‐Ulm line goes into operation / Neubaustrecke Wendlingen‐Ulm in Betrieb Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Projects First TBMs launch in London for HS2 project / Erste TBMs in London für das HS2‐Projekt gestartet Breakthrough in the Kerenzerberg tunnel / Durchschlag im Kerenzerbergtunnel The Inn district power station has been put into operation / Gemeinschaftskraftwerk Inn in Betrieb genommen New schedule and cost plan for 2nd Munich main line / Neuer Zeit‐ und Kostenplan für 2. Stammstrecke München Contract awarded for the Wendlingen Tunnel on the new Stuttgart–Ulm railway line / Tunnel Wendlingen auf der Neubaustrecke Stuttgart‐Ulm vergeben All tunnelling work in the Stuttgart basin has been completed / Alle Tunnelvortriebe im Stuttgarter Talkessel beendet Sustainable pilot project in the Filder Tunnel uses cement‐free building materials / Nachhaltiges Pilotprojekt im Fildertunnel setzt auf zementfreie Baustoffe Herrenknecht AG wins bauma innovation award 2022 / Herrenknecht AG gewinnt bauma Innovationspreis 2022 Events Award ceremony for the international Mining the Future competition / Preisverleihung für den internationale Wettbewerb Mining the Future People Obituary Dipl.‐Ing Guntram Innerhofer / Nachruf Dipl.‐Ing Guntram Innerhofer Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Projects Tunnelling work for the Obervellach II power station has been completed / Vortriebsarbeiten für Kraftwerk Obervellach II abgeschlossen Refurbished Bosruck tunnel is fit for the future / Sanierter Bosrucktunnel ist fit für die Zukunft Opening of the refurbished Belchen tunnel / Eröffnung des Sanierungstunnels Belchen Start of tunnelling for the BBT H41 "Sill Gorge – Pfons" contract section / Tunnelanschlag im BBT‐Baulos H41 Sillschlucht‐Pfons Tunnel boring machine started in Göschenen / Tunnelbohrmaschine in Göschenen gestartet Manufacturing of test element for the Fehmarnbelt Tunnel successfully completed / Erfolgreiche Fertigung eines Testelements für den Fehmarnbelt‐Tunnel Pilot project for renewal of the Elleringhausen Tunnel / Pilotprojekt zur Erneuerung des Elleringhausener Tunnels Construction of Hamburg's district heating tunnel gets underway / Baustart für Hamburgs Fernwärmetunnel Deutsche Bahn submits planning for Offenburg Tunnel ‐ Deutsche Bahn reicht Planung für Tunnel Offenburg ein Entire route of the new section of the Brenner North feeder now established / Gesamtverlauf der Neubaustrecke Brenner‐Nordzulauf steht fest Contract awarded for Gotthard main northern section / Gotthard Hauptbaulos Nord vergeben Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Great importance is attached to 'pressure‐volume records' for the execution, documentation and billing of rock grouting. In this context, special digital data management systems are now available which can provide data in a structured and consistent format that is also suitable for artificial intelligence (AI) approaches. Using datasets from a tunnel project in Scandinavia, this paper shows that artificial neural networks can be used to reliably predict the evolution of pressure‐volume records or the volume of grout injected at the end in the interests of construction site efficiency. Taking into account the technical feasibility of using AI to support tunnel grouting, we then show which contractual modifications would be required in order to make effective use of corresponding developments. [ABSTRACT FROM AUTHOR]

The Rudolf‐Fettweis hydropower plant, owned and operated by EnBW Energie Baden‐Württemberg AG, is situated in the Murg valley in the Northern Black Forest. The construction of a new underground Lower Basin is planned to upgrade the existing hydropower station. The in‐situ rock mass consists of Forbach Granite with local weakness zones, as encountered in the boreholes. Considering the extent of the project area, a 3D geological prediction model was used to allow a better interpretation of the spatial relationships of weakness zones in the rock mass and to optimize the orientation of the underground caverns. Adverse effects for the public were counteracted at a very early stage, so that the project received a high level of public acceptance. The present paper describes the current state of the project. [ABSTRACT FROM AUTHOR]

Various methods have been developed in recent decades to predict hazards associated with karst voids in underground construction. Common to all these methods is that the predicted range of water inflow is often insufficient for the purpose of implementing the planned construction works. This is usually due to an incomplete knowledge of the karst conduit system within a project area, making it difficult to predict the position and characteristics of karst voids. The method presented in this paper permits a robust prediction of karst water inflow. It is based on a combination of stochastically generated, pseudo‐genetic karst conduit systems and hydraulic modelling of the hydrogeological conditions using a Monte Carlo approach. This approach facilitates a plausible estimation of the expected range of karst‐induced water inflows and also enables the probability of encountering a karst voids. to be determined. The predictions allow for differentiated treatment of the hazards associated with karst water during the construction and operation phase of underground structures. In concrete terms, this relates to the planning and implementation of exploratory measures and ground‐improvement measures, the design of the dewatering system and its monitoring during the construction and operation phase. [ABSTRACT FROM AUTHOR]

Slow moving landslides are a common phenomenon in the Alps. Often built‐up areas, infrastructure such as motorways, water storage or stream control structures are affected by such landslides. In this paper two case studies are discussed to present a decision‐making system for the evaluation and handling of such slow‐moving landslides. [ABSTRACT FROM AUTHOR]

Abstract: Start for the first mechanised tunnel drive at the Semmering Base Tunnel / Startschuss für den ersten maschinellen Vortrieb beim Semmering‐Basistunnel TBM turns after the third shield drive in the Filder Tunnel / TVM wendet nach dritter Schildfahrt im Fildertunnel Implenia to extend Metro in Lyon / Implenia erweitert Metro in Lyon Porr to build tunnel project in Dubai / Porr baut Tunnelprojekt in Dubai DB celebrates breakthrough in the Feuerbach Tunnel / Bahn feiert Durchschlag im Tunnel Feuerbach Swietelsky to build second bore of the Karawanken Tunnel / Swietelsky baut zweite Tunnelröhre des Karawankentunnels Züblin to build Boyneburg Tunnel on the A44 / Züblin baut Tunnel Boyneburg auf der A44 Start of refurbishment of the Furka Tunnel / Auftakt für die Sanierung des Furkatunnels Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling” [ABSTRACT FROM AUTHOR]

Abstract: In April 2016 a newly formed working group began with the revision of the Austrian standard ÖNORM B 2203‐2. The goal of the group was the establishment of a practicable advance classification scheme, which would be applicable both for the design and for the construction phase. In addition, a clear separation should be established between a regular advance, which is clearly described and can be calculated by the bidding contractor, and a ”hindered advance“, which cannot clearly be described and calculated. The contractual framework is used to compensate for the regular advance, and hindering occurrences such as water ingress or increased wear are compensated by additional contractual time‐dependent costs. Fair compensation regulations for hindered advance (such as an advance through blocky rock mass, mixed face conditions, swelling, squeezing ground, major face instabilities, increased adhesion and stickiness of muck, obstacles and suspension losses) are to be defined as well. The method presented in this paper and based on systematic TBM data evaluation achieves both the goal of contractual advance classification and the goal of establishing a simple threshold differentiating regular advance and hindered advance. [ABSTRACT FROM AUTHOR]

Abstract: Nowadays, tunnels with single‐shell segmental lining are often constructed pressure‐tight using gaskets. The economic application limit of this construction type is about 50 metres head of water. If the water pressure exceeds this value, considerably more complex – and thus more expensive – two‐shell construction with an additional drainage layer between the inner and the outer lining is required. To extend the field of application of mechanized tunnelling with single shell lining in mid‐mountain formations, an innovative approach was developed based on the application of a drainage layer in the annular gap fill with a water permeability kF >10–4 m/s. The basic idea of the newly developed water‐permeable material for annular gap grouting is the use of a foam generator without a disturbing body, which foams the cement suspension in a defined way with sufficient compressive strength. Complex interrelations of material, process engineering and construction had to be considered comprehensively. The overall suitability of the developed process has been demonstrated in an extensive experimental program including field tests. The present paper focuses on the development of the construction material. [ABSTRACT FROM AUTHOR]

Abstract: Second breakthrough in Obertürkheim tunnel / Zweiter Durchschlag beim Tunnel Obertürkheim Excavation in Bossler tunnel completed / Vortrieb im Boßlertunnel beendet Double breakthrough at the underground in Lucknow / Doppeldurchbruch bei der U‐Bahn in Lucknow TBM gathers speed for the exploratory tunnel in Mauls 2‐3 / TVM für den Erkundungsstollen in Mauls 2‐3 nimmt Fahrt auf First TBM en route for phase 2 of the Sydney metro / Erste TVM für Phase 2 der Metro Sydney ist auf dem Weg Golden sleeper at Ceneri base tunnel / Goldene Schwelle im Ceneri‐Basistunnel First preliminary route designs presented for Brenner‐Nordzulauf / Erste Grobtrassen‐Entwürfe für Brenner‐Nordzulauf vorgestellt 11th VÖBU Fair and 12th Austrian Geotechnical Conference / 11. VÖBU Fair und 12. Österreichische Geotechniktagung 2019 award – Ulrich Finsterwalder Civil Engineering Prize / Auslobung 2019 – Ulrich Finsterwalder Ingenieurbaupreis Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling” [ABSTRACT FROM AUTHOR]

Abstract: The clogging of Tunnel Boring Machine (TBM) tools by soils has long been investigated, owing to the numerous difficulties arising in shield tunnelling as a result. Its occurrence leads to operation delays owing to the frequent and lengthy interventions required to unblock the soil stuck to the excavation tools and screw conveyor. Several authors have proposed laboratory tests for evaluating the clogging potential, however, those include limitations, such as not considering the clay fraction in a soil. One of these methods is the empirical stickiness evaluation, whereby a mixer and a beater are used to define a clogging evaluation parameter. Following an extended test campaign using soils with different clay contents and minerals, it became clear that this method was not adequate to provide reliable information regarding the tendency of a soil to clog in a tunnel drive. A new device was then implemented, which adds to the first method a kinetic energy impulse via dropping of the beater from a certain height. This combination of methods could provide a reasonable approximation of the potential for clogging to occur along Earth Pressure Balance Machine (EPB) tunnel drives. This paper presents the results of the proposed combined methodology for clogging evaluation, as well as the research evolution that led to the addition of the beater dropping stage. [ABSTRACT FROM AUTHOR]

Abstract: Brenner Base Tunnel: largest contract in the Austrian project area awarded / Brenner Basistunnel: Größtes Baulos auf österreichischem Projektgebiet vergeben With world record speed to the 10,000 metre mark / Mit Weltrekordtempo zur 10.000‐Meter‐Marke Multi‐mode TBM modernises Czech infrastructure / Multi‐Mode‐TVM modernisiert tschechische Infrastruktur Gemeinschaftskraftwerk Inn: Power house soon complete, challenging tunnelling works / Gemeinschaftskraftwerk Inn: Krafthaus vor Fertigstellung, herausfordernde Vortriebsarbeiten Denmark intends to bring forward work on the Danish side of the Fehmarn Belt / Dänemark will Arbeiten auf dänischer Seite des Fehmarnbelts vorziehen Breakthrough at the Untersammelsdorf Tunnel / Durchschlag beim Tunnel Untersammelsdorf CERN awards construction contract for extension project / CERN vergibt Bauauftrag für Erweiterungsprojekt DSI Underground Australia acquires Fero Group / DSI Underground Australia übernimmt Fero Gruppe Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling” [ABSTRACT FROM AUTHOR]

Abstract: The Institute of Rock Mechanics and Tunnelling at the Graz University of Technology was founded in 1992. From the beginning, the primary focus of research and development was on Alpine tunnelling and slope stability issues, considering geological conditions and their impact on construction. The aim was to improve the current practice, as well as to reduce uncertainties. The research areas can be roughly grouped into rock mass characterization, improvement of monitoring data interpretation, ground behaviour assessment, as well as development and improvement of support elements. The research is documented in about 110 master theses and 30 doctoral theses, and approximately 350 papers. [ABSTRACT FROM AUTHOR]

Abstract: First tube of the Feuerbach Tunnel broken through / Erste Röhre des Tunnels Feuerbach durchgeschlagen Rastatt Tunnel: Works continue in the east bore / Tunnel Rastatt: Arbeiten in Oströhre gehen weiter Preparations for mechanised tunnelling in Mauls / Vorbereitungen für die maschinellen Vortriebe in Mauls Breakthrough in the Eppenberg Tunnel / Durchschlag im Eppenbergtunnel ILF gains follow‐up contract at the Brenner Base Tunnel / ILF erhält Folgeauftrag für den Brenner Basistunnel Hochtief and Vinci to design and build Metro line in Copenhagen / Hochtief und Vinci planen und bauen Metrolinie in Kopenhagen Rail tunnel for Erding ring closure at Munich airport / Bahntunnel für Erdinger Ringschluss am Flughafen München Asfinag invests 1.1 billion Euros / Asfinag investiert 1,1 Milliarden Euro Risk analysis for the ”train into the clouds“ in Argentina / Risikoanalyse für Argentiniens „Zug in die Wolken” DSI takes over specialist for robotic maintenance / DSI übernimmt Spezialist für Roboter gestützte Instandhaltung Drill and blast excavation of the main tubes of the Filder Tunnel completed / Sprengvortrieb in den Hauptröhren des Fildertunnels beendet Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling” [ABSTRACT FROM AUTHOR]

Abstract: In hard rock TBM drilling, wear issues play a crucial role in the success of a tunnelling project. Thus, excavation tools must be selected carefully and be adapted to ground conditions. Wear‐related changes in the tools that occur over the course of the tools' operating lives must also be taken into account. This paper presents five basic types of macroscopic wear for cutter rings: (1) abrasive/normal wear, (2) tapering, (3) mushrooming, (4) brittle fracture of the cutter ring (special wear type 1) and (5) blockade of the roller bearing (special wear type 2). These basic wear types lead to distinct cutter ring shapes which allow deriving some fundamental characteristics of the interacting rock types. In addition, a microscopic analysis of the surfaces and associated metallographic sections from worn cutter tools has been performed. As a result, the tribological processes under the cutter, leading to tool wear, can be better understood. In summary, the investigations may contribute to a better understanding to make it easier to choose the proper TBM disc cutter for a distinct rock type in order to minimize the risk of tool‐related downtimes. [ABSTRACT FROM AUTHOR]

Abstract: For underground construction projects in the United States and Canada it is standard procedure to use a Geotechnical Baseline Report (GBR) to contractually define subsoil conditions. The GBR sets baselines based on which tunneling contractors develop bids and plan the works. Baseline values for soil abrasiveness are a focus especially where drives with pressurized‐face Tunnel Boring Machines (TBM) beneath the groundwater table and in unstable face conditions require changing the cutterhead tools under hyperbaric conditions or in pre‐constructed safe havens. Several laboratory procedures exist that can be used for providing soil abrasiveness baselines in the context of the GBR. However, none of them cover all the soil characteristics that are relevant in causing tool wear. Also, other factors need to be considered for wear rate prediction. Analyzing the performance of previous TBM drives is a proven way to gain insight into the wear system behavior. This paper presents correlation analyses of geotechnical conditions, TBM operational data, and tool wear measurements from several TBM drives in the metropolitan areas of Seattle and Vancouver, B.C. These drives with earth pressure balance and slurry TBMs include various tool types and were conducted in glacial and interglacial deposits that are considered highly abrasive. [ABSTRACT FROM AUTHOR]