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This article provides a summary of the soil investigations conducted for the construction of the S-LINK in Salzburg. The investigations included various tests such as core drillings, cone penetration tests, and seismic profiles. The results indicate relatively homogeneous conditions within the defined layers, although there is variability within the alternating sequences of fine sand and silt. The findings were used to determine soil parameters for the design and construction of the S-LINK, considering the specific characteristics of the Salzburg soil. [Extracted from the article]

The given text provides an update on the S-LINK project in Salzburg, Austria. The project aims to expand the local train network in Salzburg, with the first sub-project being the extension from the central train station to Mirabellplatz. The text highlights the importance of conducting extensive soil investigations in the Salzburg lake clay to avoid costly surprises during construction. The environmental impact assessment has been submitted, and the project company is working on planning the other sections of the project. The expansion of the local train network is expected to have positive economic benefits for Salzburg and Austria as a whole. [Extracted from the article]

This article explores the use of Tunnel Information Modelling (TIM) in the design phases of shallow tunnels. TIM helps improve the reliability of geological prognosis by representing the distribution of prognosis-reliability-classes in the model. It emphasizes the need for accurate ground information and highlights the challenges of interpreting geological investigations. The goal is to create a transparent project environment where participants can evaluate and verify geological data. The TIM method optimizes data acquisition, sharing, and use, and allows for continuous updating of the geological prognosis based on ongoing exploration results. It improves information provision, collaboration, and planning certainty in tunnel construction projects. [Extracted from the article]

The construction lot H41 Sill Gorge–Pfons is one of the biggest construction lots of the Brenner base tunnel and carries out the work on the Austrian side between Austria and Italy. It is situated between the Sill Gorge in Innsbruck and the small mountain village of Pfons. Here, tunnel excavation and inner lining concrete works are carried out based on existing caverns and tunnels made by previous construction lots E41, Sill Gorge and H33 Tulfes–Pfons. The construction lot H41 Sill Gorge–Pfons started in January 2022 with preparation works, and will take 80 months of continuous construction work to complete. All together about 22.5 km of main tubes, 38 bypasses and the remaining parts of the underground Innsbruck emergency station/stop will be excavated by the drill and blast method and by mechanised means (TBM). Additionally, concrete inner lining works will be executed partly alongside the excavation works. In the connection tunnels which are already finished and link the existing Innsbruck bypass with the new Brenner base tunnel, barrier walls are being erected and a new long‐distance water flushing system is being implemented. The limited surface areas in this mountainous region present a huge challenge for logistics and storage as well as on‐site operations for the execution of this complex underground construction lot. [ABSTRACT FROM AUTHOR]

The MRT Orange Line construction works in Bangkok are more complicated than works in earlier projects. As the tunnel alignment passes through the congested urban areas in the city, it either clashes with or passes beneath several existing structures. Underpinning works are then required. Assessment of movement of ground and structure plays an important role in the project. The rebound of piezometric pressure in sand layers that is being developed poses a major point of difficulty in the excavation and underground structure design and construction. Groundwater control measures become a crucial issue in MRT Orange Line project that leads to difficulties in deep MRT station excavations. To control base instability, various methods (e.g., cut‐off wall, staged excavation) are introduced and presented in this article. [ABSTRACT FROM AUTHOR]

The Klang Valley Mass Rapid Transit (KVMRT) project involves the construction of an urban passenger transport system, i.e., Mass Rapid Transit (MRT) system, together with the existing urban rail network, will form the backbone of the public transport system in the Greater Kuala Lumpur/Klang Valley region in Malaysia. The first MRT line implemented is the 47 km Kajang Line, of which 9.5 km is underground tunnels with seven underground stations. Construction of the line began on 8 July 2011 and achieved the full line opening on 17 July 2017. The second MRT line―Putrajaya Line―began fully operations on 16 March 2023, stretches from Sungai Buloh to Serdang and ends at Putrajaya for a length of 57.7 km, of which 13.5 km is underground tunnels with 10 new underground stations. Like all other metro underground stations/tunnels designed as part of the urban city, the KVMRT underground construction faces challenges from a technical (engineering design and construction) as well as social (environmental and land related) point of view. Needless to say, underground construction in Klang Valley is intensified with the inherent geotechnical challenges presented by complex ground conditions ranging from hard granite, heterogeneous Kenny Hill formation and extreme karstic limestone with fully developed weathered profiles to soft recent deposits including alluvium and mine tailing that is under‐consolidated in places due to past mining activities. The development of this large‐scale infrastructure project has not only opened up tremendous works and new frontier for tunnelling and geotechnical engineering in Malaysia, but it also provided a wealth of information of unique geotechnical challenges/accomplishments as well as technology breakthrough and design innovation in underground engineering. This article discusses some aspects of geotechnical challenges and interesting lessons learnt as well as numerous innovations embedded into this highly complex urban underground construction project. [ABSTRACT FROM AUTHOR]

India is well on its way to create a world‐class Mass Rapid Transport system environment as an integral part of community infrastructure development. Mumbai Metro Line 3 is one such project being constructed in Mumbai city. It comprises 33.5 km‐long underground metro corridor running along Colaba to Bandra to Santacruz Electronic Export Processing Zone. It includes 27 stations (26 underground and 1 at grade), depot and associated twin‐tube tunnel. Mumbai Metro Rail Corporation Ltd., an affiliate organisation of Mumbai Metropolitan Region Development Authority, is responsible for the implementation of the project. Excavation and tunnelling works posed significant challenges as they cross densely inhabited zones of Mumbai. There were several buildings which were old and in delicate condition, many of which were heritage structures. In Mumbai – being a coastal city – the water table is almost at ground level which added to complications. There were several utilities, many of which were lifeline utilities, which could not be diverted or even closed, thus requiring support during excavation. Likewise, ensuring traffic movement with minimal disruptions with enormous excavation works for the project required several innovative solutions. Other criticalities included low overburden to the existing flyovers and to the air traffic control tower as well as saving a 100 year‐old banyan tree. [ABSTRACT FROM AUTHOR]

The new Ontario Line is one of four priority transit projects announced by the province of Ontario in 2019 for the Greater Toronto Area (GTA). It will be a 15.6 km stand‐alone rapid transit line that will run through the city from Exhibition/Ontario Place in the southwest, through the heart of downtown Toronto, all the way to the Ontario Science Centre in the northeast. Over half of the route (9 km) is planned to run underground through new tunnels, with the remainder running along elevated and at‐grade rail corridor sections of track. Fifteen new stations are proposed, whereby eight are planned as deep underground structures. Most of these underground stations will be built in the downtown core, with numerous connections to the broader transit network of the GTA, including GO Transit rail services, the Toronto Transit Commission's (TTC) existing subway Lines 1 and 2, the Line 5 (Eglinton Crosstown LRT) currently under construction, as well as numerous bus and streetcar routes. The expected project benefits of Ontario Line are as follows: A faster and more reliable access to rapid transit system with more than 227,500 people living within walking distance to the new line.Reduction in crowding of existing Line 1 subway.Up to 47,000 jobs accessible by transit in 45 min or less for Toronto residents.Economic and community growth along the future transit line and significant reduction in traffic congestion and greenhouse gases by providing alternative transportation options. The Ontario Line is currently being delivered through a number of contracts with different procurement approaches. [ABSTRACT FROM AUTHOR]

In 2013, the Austrian Society for Geomechanics published the Guideline for the Geotechnical Design of Underground Structures with TBM Excavation. The Guideline contains general procedures for the geotechnical design and construction. In the design phase, the first steps are evaluating different ground conditions by classifying different ground types, different ground behaviours, their categorization into ground behaviour types, and the determination of construction measures derived from the ground behaviour. On this basis the expected system behaviour in each system sector of the tunnel boring machine (TBM) is predicted and described in detail to enable comparison in the construction phase. In the construction phase, geotechnical relevant ground parameters as well as observations regarding the actual system behaviour are recorded and compared with the assumptions of the design. The geotechnical design is updated continuously based on the encountered ground conditions and geotechnical observations. The improved quality of the geotechnical model allows an optimization of the construction while meeting all safety and environmental requirements. In the first part of the article, the general procedures of the guideline are described and parameters to describe the system behaviour in each system sector adequately are listed. In the second part of the article, the implementation of the guideline during design and construction at the Semmering Basetunnel in Austria is described. [ABSTRACT FROM AUTHOR]

The handling of a tunnel construction project poses great challenges for all those involved. Variables that cannot be clearly quantified can arise during the entire process of the project. The subsoil in tunnelling is one of these parameters which is difficult to forecast. The geological and hydrogeological conditions must be assessed during the planning phase with the help of exploratory measures and from the experience from projects that have already been built. During the execution work, deviations from the documents on which the target determination is based occur in almost all underground construction projects. These changes can either cause a change in the construction process and/or lead to a different construction time in relation to the calculated duration. Based on this initial situation, the development of an innovative contract and remuneration model for machine tunnelling appears to be important. The main focus of the model is to generate a transparent and comprehensible method of how the remuneration‐worthy portion can be calculated in the case of a different construction time in mechanised tunnelling. In order to ensure this transparency and traceability of the system to be developed, the data records that can be digitally recorded during the tunnelling work are used as a fundamental basis for the created model. [ABSTRACT FROM AUTHOR]

CERN (Conseil Européen pour la Recherche Nucléaire) is the world's largest research centre for high‐energy and particle physics. The research infrastructure contributed to the greatest successes in the field of experimental physics. A new, approximatively 91 km long subsurface infrastructure connected to the existing particle accelerator complex is being conceived in the frame of the Future Circular Collider. It would serve a global community of researchers with two subsequently operated particle colliders until the end of the 21st century. Even at an early stage of such a project, comprehensive investigations have to be carried out into the nature of the subsoil in order to find an optimal utilisation strategy for the excavated material in accordance with the national and international regulations in order to promote the recycling of excavated tunnel material in terms of resource conservation and the improvement of the sustainability of underground construction projects. [ABSTRACT FROM AUTHOR]

Sustainability is a guiding principle for political, economic and ecological action, which in companies, societies and countries all over the world, is based on the following three pillars: ecology, economy and social aspects. With the associated worldwide efforts to reduce emissions, this topic has also arrived in the construction industry in general and thus in tunnel construction in particular. In addition to the actual planning, construction, use and maintenance of mined structures, tunnel builders certainly have a special role to play, since the creation of underground structures relieves overground structures and can also change living space for the better. However, the influences and impact must always be considered in the overall context of all three pillars of sustainability – and in our fast‐paced times, this requires a considerable change in mindset as well as a clear change and expansion of the assessment standards. The following article draws a current picture of "sustainable tunnelling" on the basis of four sub‐sections that describe selected tasks and approaches from the perspective of operators, planners, the construction industry and science as a basis for discussion. [ABSTRACT FROM AUTHOR]

West Link (Swedish: Västlänken) is one of the biggest infrastructure projects in Sweden building an in total 8 km double‐track railway tunnel in Gothenburg, which is currently under construction. "E05 Korsvägen" is a construction lot which is part of the West Link project with the Swedish transport authority Trafikverket as the client. The works were awarded to the Joint Venture (JV) West Link Contractors consisting of Wayss & Freytag Ingenieurbau AG and NCC. A special contract model with a design and build part combined with a regular bill of quantities comprises building an underground double‐track railway tunnel with a length of 3.2 km and the new Korsvägen station. This sub‐project includes three drill and blast sections and three open excavation sections. All three construction pits will be executed in challenging soft ground conditions. The JV is confronted with high environmental demands and special requirements for the blasting works in the urban area of Gothenburg. [ABSTRACT FROM AUTHOR]

Tunnel construction is not immune to the climate crisis – here too there is an urgent need to improve the carbon footprint. The production of concrete and consumption of cement cause climate‐damaging CO2 emissions. A tunnel with a 10 m diameter, for example, generates around 10 t of CO2 per linear metre. The main priority is thus to reduce the amount of concrete and steel reinforcement used and to select low‐carbon cements and binders, as well as employing single‐shell construction methods suited to the requirements of the construction project. We need to consider practical approaches to reducing concrete volumes which go beyond structural requirements. CO2 reduction in tunnelling starts with the design and approval process, so financial incentives must be built into award criteria and construction contracts. This article aims to highlight ideas which in future will play an increasingly important role in the design of underground construction works than is currently the case. Although many well‐established work practices and design details in underground construction are based on decades of experience and are bound by normative and contractual framework conditions, it is now time to re‐examine the facts and consider new ideas that reflect the need to reduce CO2 in concrete construction. [ABSTRACT FROM AUTHOR]

Tunnelling and underground construction is a material‐intensive undertaking that involves the use of large quantities of concrete. Analyses of the life‐cycle assessment of a new tunnel show that the carbon footprint is largely determined by cement and concrete consumption. Optimising the quantity used, composition and properties of this construction material is thus crucial to reducing ''grey'' emissions – CO2 emissions arising from the construction phase. While strength and durability requirements along with exposure classes are clearly set out in directives and tender specifications, CO2 emissions per cubic metre of concrete are not currently considered a relevant criterion when it comes to project design, award and implementation. And this, despite the fact that the current state of knowledge and research shows that substantially lower‐carbon concretes could be used than is generally the case today. A paradigm shift is required to achieve the goal of carbon neutrality in the construction industry. This paper shows how CO2 emissions per cubic metre of concrete can be declared and reduced in tunnel construction, and how concrete recipes can be formulated using climate‐friendly materials, while maintaining the required strengths and durability properties. Using the design approaches outlined here, it is possible to increase clinker efficiency and reduce CO2 intensity without adversely affecting the structure and its functionality. [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]

When it comes to underground structures, water ingress from the surrounding formations leads to several environmental, economic and sustainability issues. To obtain the sealing, the grouting of rock fractures is done. Today, in the grouting operations, which are commonly conducted in almost all the tunnel and subsurface infrastructure projects, the pressure applied is static. This type of applied pressure might be suitable for the large fracture apertures > 100 μm, but it has been acknowledged that it is difficult to obtain sufficient penetration through smaller apertures, where filtration of cement particles starts to occur. Research is already done to overcome this issue by applying dynamic grouting pressure instead of static. It was proved that this approach erodes the formed filter cakes and improves grout penetrability in fractures below 100 μm. This research focuses on low‐frequency rectangular pressure impulse as an alternative to other methods. The goal is to improve grout spread in micro‐fractures (especially in apertures < 70 μm). During the investigation, a prototype dynamic injection equipment was built and tested under laboratory conditions. The 4 m variable aperture long slot (VALS) was used in the experiments to simulate rock fractures. The test showed better grout penetrability using dynamic pressure approach. At the current time of writing this article, preparation works are done for field test of prototype equipment at SKB Hard Rock Laboratory (HRL) at Äspö, Sweden. [ABSTRACT FROM AUTHOR]

The installation of pipe umbrella systems is a complex process that requires well‐trained machine operators and installation crews. Due to project and time constraints, adequate operator training in a safe environment without risk of personnel accidents or machine damage often falls victim to cost cuts. Previously, this shortcoming has been compensated by the deployment of selected expert personnel to respective tunnel projects for a certain period. This practice is, however, limited to availability of expert personnel and associated with high travel costs and significant waiting time on‐site. Virtual reality (VR) simulator‐based trainings have become state‐of‐the‐art in underground construction. They provide enhanced occupational safety by conducting virtual training before commencing works in the tunnel, increased operator performance, and improved installation cycle times. In addition to basic training, the VR simulator can be used for assembly and commissioning, maintenance, as well as refresher trainings and ongoing just‐in‐time support. Around mid‐2019, DSI Underground initiated the development of a realistic and authentic scenario‐based VR simulator for the AT – Pipe Umbrella System. This training tool also includes extensive theory background supported by a series of video modules illustrating best underground work practices. This article illustrates the background and development plan of the VR simulator and the implementation based on use cases. [ABSTRACT FROM AUTHOR]

The construction phase of underground railway stations executed with top‐down method is often susceptible to a considerable number of interferences. The interference between the excavation of the Florence high‐speed station and tunnels' execution is a critical element of the Florence underpass project, which foresees the simultaneous construction of the two infrastructures. The project's complexities and the interference between the various construction phases have been studied and resolved by developing the entire project in a Building Information Modeling (BIM) environment. In particular, the implemented four‐dimensional (4D) BIM model managed to simulate the possible macrophases and identify an optimal construction solution or, at least, the crucial actions to be taken to ensure the simultaneous construction of the station and tunnels. The 4D BIM model allowed an accurate simulation of the specific critical construction phases by identifying spatial interferences between completed works, temporary structures, and overlapping interventions. Consequently, it was possible to adopt appropriate technical solutions and develop a reliable work plan. In addition, it was possible to verify the potential scenarios of the TBM passage through the excavated station, which allowed to foresee some specific interventions needed to ensure works' continuity. The BIM methodology also allowed to find optimal solutions in a reasonable time, preventing a significant use of resources. [ABSTRACT FROM AUTHOR]

In tunnel construction there is a clear need for specific contractual regulations, as unforeseen events make it far more difficult to predict the construction measures required than is the case in above‐ground construction. Tunnel construction contracts must make provision for all such events associated with changes in performance to ensure conflict‐free invoicing wherever possible. Conflict avoidance begins at the tender phase. In addition to the two ÖNorm B 2203 standards, the Guideline for the Geotechnical Design of Underground Structures with Conventional Excavation is an important basis for tunnelling contracts. Austrian standard ÖNorm B 2118 also plays a major role in tunnel construction as the agreed contractual basis in most cases. It contains contractual provisions for building services based on the partnership model and is intended for large‐scale projects and complex construction works. In future, other alternative contract models with a partnership approach could become an even greater focus of attention. For instance, the alliancing contract model is particularly suitable for complex, technically challenging projects requiring innovative solutions. The early involvement of all key project participants is intended to reduce design errors and encourage innovation. [ABSTRACT FROM AUTHOR]

To relieve congestion on the S‐Bahn main line in Munich (urban railway), a second main line is being built over a length of 10 km, with more than 7 km of tunnels and three new underground stations. These new stations at Hauptbahnhof, Marienhof and Ostbahnhof each have a length of about 250 m and are located at depths of up to 45 m. The stations mostly have a central staircase, which will be constructed using the top‐down method with building pits enclosed by diaphragm walls. The platform tubes subsequently constructed using NATM, with a 40 m wide cross‐section consisting of five tubes, have an overall excavation cross‐section of approx. 450 m2. This paper presents the evaluation of the calculated building settlements due to a construction process comprising groundwater drawdown, building pit construction, platform tubes constructed using NATM, traffic tunnels constructed using TBM, and the exploration and rescue tunnel located between the two traffic tunnels, using the Marienhof West station as an example. To perform the evaluation it is necessary to superpose all settlements arising from the different construction stages for each structure, which in some case are calculated across planners and construction sections. From these superposed calculated settlements, the corresponding angular distortions are calculated according to the type of curvature, i.e. concave type or spandrel type of settlement, and compared with the permissible limit values. [ABSTRACT FROM AUTHOR]

The use of geophysical methods for the planning of complex underground structures such as deep tunnels has made significant progress in the last two decades. The realization of large underground construction projects in complex geological environments has led to an increase of geophysical exploration during excavation activities, drilling, and geological documentation. The aim is to continuously update and improve the geological model in order to identify and mitigate potential risks. Flexible planning of geophysical measurements and their fast and efficient implementation are required to minimize the impact on ongoing construction works. During construction of the Semmering Base Tunnel geophysical measurements were and are used to supplement exploratory drillings and tunnel documentation. This paper presents results from the construction lots SBT1.1 (Gloggnitz) and SBT3.1 (Grautschenhof) with an emphasis on carbonate prediction, and from the Göstritz cavern where sudden water ingress required an update of the geologic model. For each assignment a tailored‐made geophysical methodology was designed and applied. [ABSTRACT FROM AUTHOR]

The Design and Build project "Metro Doha Green Line Underground" has been awarded to a joint venture composed of Porr, the Saudi Bin Ladin Group and HBK in summer 2013. It contains the "ready to use" construction of the underground part of the Green Line with 2 × 17 km tunnels, six stations, switching areas as well as cross passages and emergency exit shafts. The 34 km of tunnelling, realized with six EPB machines simultaneously, have been completed in only 18 months. The main impact on the determination of the design and build specification in terms of the segmental ring design is based on the extraordinary geological environment properties of the project area of Doha City. The geology is characterized by a dominating 3‐rocklayers system comprising massive upper and lower limestone deposits, which are commonly separated by a thin shale layer. Additionally, and in regard to the nearby located sea‐side the type of identified aggressive exposure conditions relevant to the concrete segment lining in terms of significant sulphate and chloride impact requires a durable reinforcement solution fit for required 120‐year service life. Especially due to chloride attack an ordinary steel bar reinforcement system including a projected 90 mm nominal concrete cover at lining's intrados and extrados turns out statically difficult and constructionally non‐practicable. Therefore, steel fibres are chosen to meet the strict design constraints. [ABSTRACT FROM AUTHOR]

Base tunnels usually require temporary intermediate construction accesses in order to be able to carry out the tunnelling work in a timely, economical and logistical reasonable scope. Intermediate construction accesses in the form of shafts lead to particular logistical challenges in supplying the tunnel headings. At contract SBT 1.1‐Tunnel Gloggnitz as the eastern section of the Semmering Base Tunnel, the shafts of the intermediate construction access Göstritz cannot be sunk from the surface for topographical reasons but are instead developed by an access tunnel. This fact requires the construction of complex underground structures and logistical interfaces to supply the four tunnel headings, beginning from the building site facilities, via the access tunnel, through the shafts to the tunnel face. In addition to the ongoing supply of all kinds of support measures, the excavated material is mucked by means of fully automatic belt and shaft conveyor systems. To ensure the permanent safety of the crew on‐site, the highest demands and resilience are placed on the transport systems through the two 250 m deep shafts, the ventilation and the mountain water drainage systems of up to 500 l/s. The article describes the experience and ongoing optimization of the logistics concept as well as innovative new developments that are applied in this special tunnel project. [ABSTRACT FROM AUTHOR]

Projects Construction of the Tauernmoos pumped storage power station gets underway / Baustart für das Pumpspeicherkraftwerk Tauernmoos Federal Council approves Rheintunnel Basel general project / Bundesrat genehmigt generelles Projekt Rheintunnel Basel Initial break‐through under the Eisack / Erster Durchschlag unter dem Eisack Expansion of underground railway (U‐Bahn) station in Vienna / U‐Bahnausbau in Wien Call to tender issued for Brenner Base Tunnel contract section H41 Sillschlucht‐Pfons / Brenner Basistunnel schreibt Baulos H41 Sillschlucht‐Pfons aus 2. Munich trunk route: Rotary tower crane erected at Marienhof / 2. Stammstrecke München: Turmdrehkran am Marienhof aufgestellt New Berlin underground railway U5 in operation / Neue Berliner U‐Bahnlinie U5 in Betrieb Education and Training A specialist in tunnelling – the new education and training for blue‐collar‐worker / In vier Monaten zur Fachkraft im Tunnelbau Companies Sandvik acquires DSI Underground / Sandvik übernimmt DSI Underground BASF Bauchemie to become MBCC Group / Bauchemie von BASF wird zur MBCC Group Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Breakthrough of Rosenstein S‐Bahn tunnel / Durchschlag für S‐Bahntunnel Rosenstein InnoTrans postponed until 2022 / InnoTrans auf 2022 verschoben Breakthrough of third tube in Gubrist Tunnel / Durchschlag 3. Röhre Gubristtunnel ÖBB refurbishes the Karawanks Tunnel / ÖBB modernisiert den Karawankentunnel Tunnel driving under the Eisack / Vortrieb unter der Eisack ITA Tunnelling Awards list of finalists disclosed / Finalisten für den ITA Award Kühtai development: contract awarded for main contract section / Kühtai‐Ausbau: Zuschlag für Hauptbaulos erfolgt Deutsche Bahn awards contracts for Stuttgart 21 track construction / Bahn vergibt Aufträge für den Gleisbau von Stuttgart 21 Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

The construction of underground structures in metro rail projects is always challenging as the project works normally affect a large number of adjacent surface structures with stringent settlement criteria and protection requirements. Project implementation becomes even more complex when the overburden is shallow and the area of the cross‐section is comparatively large. In the case of design and build metro rail projects, the Client provides a tender stage design to the Contractor's designer; this initial design is often based on limited data and does not consider the construction phase in detail. This is a significant challenge for the Contractor's designer as the new design has to consider all relevant parties and boundary conditions with respect to the compatibility of other parts of the project. This paper describes such a challenge at Mumbai metro line 3, where a crossover structure had to be implemented during the detailed design as a change of scope. The initially proposed crossover cavern was re‐arranged during the detailed design. The main emphasis of this paper is to explain the revised crossover arrangement, for optimized construction feasibility, construction staging and geotechnical stability of the excavation. After the options presented by the Contractor's designer met the original objectives, the detailed design of the primary support and modified construction sequence was carried out in accordance with the principles of NATM design. [ABSTRACT FROM AUTHOR]

Infrastructure in large cities is getting denser over time. Therefore, interferences with existing structures and complying to project constraints are fast becoming a very common feature during the implementation process of new projects in urban areas. As a consequence, actual geotechnical challenges often require application of innovative methods of construction in order to minimize potential construction impact or disruption. The paper intends to direct the focus on the application of unusual construction methods and will highlight and discuss some very specific solutions to some major challenges of constructing underground projects in urban environments. This is presented in the form of examples applying unusual construction methods for underground structures related to shallow overburden situations such as passenger linkways, which do not normally stand in the forefront of the attention. The paper is written from the viewpoint of a practitioner, who is deeply involved in the actual design for the implementation of such projects. [ABSTRACT FROM AUTHOR]

The aim of this project is to achieve a uniform and comparable method for the technical assessment of the state of structures throughout Germany (for bridges, tunnels, culverts; in general, for underground and support structures). By clustering defects, damage and measures according to their relevance to the technical condition of the structures, it is possible to make a more precise analysis and compare the repair and investment requirements for the system. This makes it easier for DB Netz AG to prioritize work and allocate the necessary resources. For the end user, the new process management and the support for damage assessment provided by the newly introduced damage catalogue, including pictures of the damage, is an essential part of uniform comparability and also ensures the transfer of know‐how necessary for the actual work to be done. The article provides an insight into the progress with the project to date, the current state of the work and an outlook for the introduction of the new procedures for tunnels and culverts. [ABSTRACT FROM AUTHOR]

BIM modelling of infrastructure works is controlled by a global market consisting of few software suppliers and is contingent upon the functions provided by them. Customization options furnished by the software suppliers often enable enhancement of functions, which is essential for infrastructure BIM although not completely available. This enables improved interoperability of the software tools used in this area. IFC is most likely to become an established international format for data exchange with its constant but also intricate further development. However, in underground infrastructure construction, both international and national standards are used and the integration of the latter in IFC cannot be anticipated. Hence, the implementation of BIM has to apply national standards in the use cases of collaborative data exchange among the different disciplines in tunnelling. In this contribution, the use case of payment of excavation classes and its implementation in a BIM environment are addressed. It discusses the interoperable interlinkage of software tools commonly used in construction to generate consistent digital data transfer and it underscores the need for an interdisciplinary agreement to integrate national standards into adequate practice for the implementation of BIM. [ABSTRACT FROM AUTHOR]

The digitalisation of many areas of the economy is progressing, also in construction, where the intention is to provide information about built facilities for decision‐makers concerning the design, building and operation of construction works in a consistently high quality, easily read and data‐based. Until now, digitalisation in construction has been retarded by the high complexity of construction, which should however now rapidly change. The DAUB recommendation "Digital Design, Building and Operation of Underground Structures" is intended to make a contribution in this regard. Recommendations from the German Tunnelling Committee DAUB normally represent "best practice" solutions from German tunnelling. For Building Information Modelling (BIM) in tunnelling, there is not however yet sufficient experience. There have indeed been many solutions on projects but there is a lack of the appropriate standards for systematically applicable industry‐wide solutions. The DAUB recommendations show how appropriate standards can be created. The following article discusses selected themes from the DAUB recommendations. [ABSTRACT FROM AUTHOR]

Brenner Base Tunnel half excavated / Brenner Basistunnel zur Hälfte ausgebrochen Grouting Fundamentals & Current Practice / Grundlagen und aktuelle Praxis der Injektion Tunnel Conference Innovation Prize / Innovationspreis Tunneltag GKI site in Ovella running at full speed again / GKI‐Baustelle in Ovella läuft wieder auf Hochtouren Construction design for the second road tunnel at the Gotthard approved / Ausführungsprojekt für zweite Straßenröhre am Gotthard genehmigt 20 years of Erkat – three years under Epiroc / 20 Jahre Erkat – drei Jahre unter Epiroc Tsurumi pumps – dynamics in European business / Tsurumi Pumpen – Dynamik im Europa‐Geschäft S‐Bahn tunnel under the Rosenstein Park broken through / S‐Bahn‐Tunnel unter dem Rosensteinpark durchgeschlagen London Power Tunnel awarded / Londoner Stromtunnel im Wert vergeben Andesite is the rock of the year 2020 / Andesit ist das Gestein des Jahres 2020 Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

The closing of the gap in line U5 of the Berlin underground completes the missing connection between the Alexanderplatz and Brandenburger Tor stations. The existing line U5 currently ends at the Alexanderplatz. With the closure of the gap, the existing tunnels at the Berliner Roten Rathaus will be connected to the Brandenburger Tor station on the line U55. The project includes the construction of three new underground stations and two single‐track tunnels connecting them, which are being tunnelling by shield machines. The new alignment thus passes deep under the city, under the River Spree, the new Berliner Schloss and the Spreekanal as well as running along beneath the street Unter den Linden to the Brandenburger Tor. The construction activities are taking place right in the centre of Berlin and the particular local conditions are a logistical and technical challenge. [ABSTRACT FROM AUTHOR]

The U2 station Neubaugasse will become one of the busiest interchange stations in the Vienna underground network, with passengers changing between the existing line U3 running along under the Mariahilfer Straße and the new line U2 crossing the Mariahilfer Straße. The Mariahilfer Straße, one of the best known shopping streets in Vienna with shopping centres and high numbers of passers‐by in the middle of a densely built‐up residential area, and its side streets have been redesigned in the last few years with the aim of traffic calming and creating new public spaces. The building of an underground railway station in such surroundings thus poses a great challenge. Extensive soil investigations, house strengthening measures and utility diversions were carried out in advance. The shafts were constructed top‐down in restricted space conditions. Due to the scarcity of available site facilities areas, deliveries to the site are only possible "just‐in‐time". Access for local inhabitants and delivery traffic to the side streets, and also for emergency services, has to be maintained during the construction period. [ABSTRACT FROM AUTHOR]

The interaction of tunnel boring machines with the rock mass is highly influenced by human, technical and geological factors. Interpretation of geological observations and TBM data is currently done on a subjective basis. Technologies based on Artificial Intelligence research, can be used to automatically classify TBM data into rock mass behaviour types. Albeit first results look promising, any technology poses the threat of malicious use that deliberately harms / benefits one or another party. This paper shows how an Artificial Neural Network (ANN) can be trained to achieve the best possible rock mass behaviour classification, or how such a system can be misused to yield a more optimistic, respectively pessimistic classification to fortify the interests of one party. However, ANN also pose the chance to serve as an independent objective opinion and to improve the self‐consistency of geological classifications. [ABSTRACT FROM AUTHOR]

Tunnel groundbreaking on the Pfons‐Brenner contract / Tunnelanschlag für das Baulos Pfons‐Brenner Successful use of a refurbished TBM in Den Haag / Erfolgreicher Einsatz einer sanierten TVM in Den Haag Breakthrough for the north TBM at the Gemeinschaftskraftwerk Inn (GKI) / Durchschlag der Tunnelvortriebsmaschine Nord beim Gemeinschaftskraftwerk Inn (GKI) Construction works in the Mosi Tunnel completed / Bauarbeiten am Mositunnel beendet Züblin hand over the Albabstieg Tunnel to the Deutsche Bahn / Züblin übergibt Tunnel Albabstieg an die Deutsche Bahn Strabag starts extended contract for polyhalite mine in Great Britain / Strabag beginnt erweiterten Auftrag für Polyhalit‐Bergwerk in Großbritannien DEGES publishes a BIM guideline and supplementary documents / DEGES veröffentlicht BIM‐Leitfaden und ergänzende Dokumente Walter Wittke Prize 2020 / Auslobung Walter‐Wittke‐Preis 2020 Five approximate routes for the Brenner north approach / Fünf Grobtrassen für den Brenner‐Nordzulauf 40th Annual Short Course – Grouting Fundamentals & Current Practice, 1st European Edition Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Even in the 1920s were already the plans for hydropower exploitation of the upper River Inn. Since the resumption of design work, the Gemeinschaftskraftwerk Inn (GKI) project has been optimised and adapted to the latest state of the technology as well as ecological requirements. After a collaborative process involving the authorities from both countries, the start of construction could be approved in 2014. The project will build a diversion hydropower station with an annual generation of about 414 GWh in the border area of Switzerland and Austria. [ABSTRACT FROM AUTHOR]

Rock bolting in tunnelling and mining has been used for more than 100 years. The mechanism of how anchors behave, application and patterns have evolved into standard practices for all types of underground excavation. Passive acting bolts and dowels, as well as the active pre‐tensioned bolts act in a way to limit shear and are subject to tension, which nails the rock mass together. Injection is used in underground structures to manage water ingress and less often to reinforce the rock mass systematically. Typically, the injected cementitious material fills the cracks and fissures in the rock mass and increases the shear resistance within the treated area. The use of pumpable, thixotropic, water insensitive, fast reacting resins to encapsulate rock bolts potentially offers to combine the nailing and shear resisting effect of the bolts with an injection approach. When using an accurately controlled pressure and volume regime, the rock mass can be bonded together, resulting in a significant improvement of the overall rock mass properties. A new rock bolt anchoring resin has been developed to improve the efficiency of underground support combining the positive effects of rock bolting and injections as outlined above. The driving idea behind this concept and test results are discussed in this paper. [ABSTRACT FROM AUTHOR]

Full upgrading of the Klaus tunnel chain completed – Vollausbau der Tunnelkette Klaus abgeschlossen Two new EPB machines for the Istanbul Metro – Zwei neue EPB‐Maschinen für die Metro Istanbul Three main construction contracts for the 2nd main line in Munich awarded – Drei Hauptbaulose für die 2. Stammstrecke in München vergeben Contract for the Rudersdorf Tunnel awarded – Auftrag für Tunnel Rudersdorf vergeben DB completes investigation drilling for the Brenner north approach in the Inntal – Bahn schließt Erkundungsbohrungen für den Brenner‐Nordzulauf im Inntal ab 14 km Tunnel to improve electricity supply in Stockholm – 14‐km ‐Tunnel für den Ausbau der Stockholmer Energieversorgung Gallery for the Argenbach small hydropower station awarded – Stollen für Kleinwasserkraftwerk Argenbach beauftragt Slate: rock of the year 2019 – Schiefer: Gestein des Jahres 2019 Skanska to build tunnel in north Norway – Skanska baut Tunnel in Nord‐Norwegen WTC 2019: Technology and innovation meet archaeology, architecture and art – WTC 2019: Technik und Innovation treffen Archäologie, Architektur und Kunst Call for papers – Themes for the next issues of Geomechanics and Tunnelling – Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Underground construction sites represent a complex challenge for all project participants. Precisely in the area of health and safety as well as fire safety, therefore, good coordination is necessary in order to successfully counteract the increased accident and health risks. Clear definition of tasks and responsibilities is therefore essential. Through a continuous risk management process, it is possible to ensure from the design phase to the construction phase that risks can be minimized in advance and that the best risk reduction measures can be derived. The Guideline and Regulation for the Planning, Construction and Maintenance of Roadways (RVS) 09.01.51 "Health and Safety on underground construction sites" provides the necessary basis for this and thus represents an essential tool for all project participants to improve the level of safety. [ABSTRACT FROM AUTHOR]

The Salzburg S-LINK project aims to connect Salzburg's main railway station with the south of the city and later with the city of Hallein. The project involves extensive soil investigations and faces various geotechnical and construction challenges. The article provides an overview of the project, summarizes the results of the soil investigations, and highlights the challenges involved. It also includes other articles on topics such as shallow tunneling, subway construction, and various tunnel projects around the world. [Extracted from the article]

The new Tauernmoos power plant is an important cornerstone for the supply of traction power from hydropower. The project includes the construction of an underground powerhouse with a length of 73 m, a width of 25 m, and a height of 40 m. In addition, 11.5 km of tunnels and galleries were excavated for the project, for which DSI Austria supplied the complete range of ground support means. (photo DSI Underground Austria) [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: Final breakthrough in the Granitztal tunnel chain / Letzter Durchschlag bei der Tunnelkette Granitztal Road tunnel under the Suez Canal broken through / Straßentunnel unter dem Suez‐Kanal durchgeschlagen Mechanised driving of the north bore of the Albvorland Tunnel started / Maschineller Vortrieb in der Nordröhre des Albvorlandtunnels gestartet Groundbreaking for third bore at Gubrist / Anschlagdritte Röhre Gubrist Chinese TBM for Blacksnake Creek Project in Missouri / Chinesische TBM für Blacksnake Creek Projekt in Missouri Wayss & Freytag wins contract for the Göteborg West Link / Wayss & Freytag erhält Auftrag beim Göteborg West Link Strabag to build a section of the Stockholm motorway ring / Strabag baut Abschnitt des Stockholmer Autobahnrings Breakthrough in the Bözberg Tunnel / Durchschlag im Bözbergtunnel Technical equipment of the new line from Wendlingen to Ulm awarded / Technische Ausrüstung der Neubaustrecke Wendlingen‐Ulm vergeben Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling” [ABSTRACT FROM AUTHOR]