Artikeldatenbank
Autor(en) | Titel | Zeitschrift | Ausgabe | Seite | Rubrik |
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Hödl, Reinhold; Bach, Dietmar; Lehner, Wolfgang | Execution of tunnel construction projects - analysis of the current situation / Abwicklung von Tunnelbauvorhaben - Analyse der Ist-Situation | Geomechanics and Tunnelling | 6/2021 | 771-780 | Topics |
KurzfassungThe situation on the sites of large tunnel construction projects has become increasingly tense in recent years. On all sides, the implementation of these projects suffers from economic constraints, which inevitably lead to a decline in the culture of dialogue and a deterioration in personal relationships. A solution to this problem cannot be achieved by simple calculations or rules. It is much more a matter of working out new alternative paths and possibilities together, and then taking them. However, those responsible and, above all, those involved on the ground must be able to take this step, and be allowed to do so. x | |||||
Deutschmann, Daniel | Alliance Contracts - Without litigation through the crisis / Allianzverträge - Ohne Rechtsstreit durch die Krise | Geomechanics and Tunnelling | 6/2021 | 782-793 | Topics |
KurzfassungClaim- and anti-claim-management is becoming increasingly important on construction sites. More and more (human) resources from contractor and owner are being invested in projects for this purpose. This is clearly counterproductive for the success of the project, since claim and anti-claim-management do not create any added value in the project and the actual target of a construction project is pushed into the background. In this article, the differences between plannable and dynamic-complex systems are used to show, where classic construction contract models reach their limits and which projects are better implemented with alternative contracts. Based on the Alliance Contract for the successfully completed project “Triebwasserweg Maria Stein”, it is shown why Alliance Contracts are more suitable than classic contract models for dynamic-complex (risky) large-scale projects, such as large tunnel projects in difficult geology. By choosing the right contract model for the project, the best project results can be achieved, and legal disputes can be avoided even in crisis situations. x | |||||
Ertl, Hannes; Hechenblaickner, Kurt | The Emerald Book - A milestone on the road to the future / Das Emerald-Book - Ein Meilenstein auf dem Weg in die Zukunft | Geomechanics and Tunnelling | 6/2021 | 794-800 | Topics |
KurzfassungThe Emerald Book as a joint work of ITA and FIDIC is the first international standard for contracts in tunnelling and shows the necessity and the need for such regulations. The Geotechnical Baseline Report is the key element and can be combined with Austrian regulations such as ÖN B2203 and the guidelines of the Austrian Society for Geomechanics. Characterised by a balanced risk sharing and embedded in the FIDIC suite, the Emerald Book is an attractive alternative to Central European contracts. x | |||||
Klösges, Simon; Müller, Michael | Artificial ground freezing as a consolidation measure for tunnelling under Bern main station / Erstellung eines Gefrierkörpers als Bauhilfsmaßnahme für einen Tunnelvortrieb unter dem Hauptbahnhof Bern | Geomechanics and Tunnelling | 5/2021 | 441-447 | Topics |
KurzfassungIn the course of the planned underground extension of the central station in Bern, an access tunnel had to be constructed from an existing shaft. The first 60 m of this tunnel cross through unstable, water-bearing and unconsolidated rock, and run under existing railway tracks. Thyssen Schachtbau GmbH has been commissioned the contract to carry out an artificial ground freezing measure to enhance the realization of the tunnel construction. The horizontal directional drilling work within the shaft as well as the construction and operation of the freezing plant were carried out in 2020 in a very confined space, and parallel to the ongoing operation of the train station. In order to ensure sufficient water saturation and thus the freezability of the unconsolidated rock, artificial ground irrigation procedure was operated. After completion of the predefined frost body, the tunnel was successfully and safely driven from the shaft into the bedrock. x | |||||
Höser, Sebastian; Bathaeian, Iman | Settlements in urban areas - Evaluation of building settlements as a result of complex underground constructions / Oberflächensetzung im urbanen Raum - Auswertung der Oberflächensetzungen an Gebäuden infolge komplexer unterirdischer Bauabläufe | Geomechanics and Tunnelling | 5/2021 | 448-456 | Topics |
KurzfassungTo 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. x | |||||
Sempelmann, Franz; Matt, Kajetan; Konrad, Frank | The A26 Linz Motorway - A new landmark for Linz / Die A26 Linzer Autobahn - Ein neues Wahrzeichen für Linz | Geomechanics and Tunnelling | 5/2021 | 459-467 | Topics |
KurzfassungThe A26 not only relieves the central part of the road network in Linz but also allows the river Danube to be crossed by means of a 300 m long bridge, anchored in the rock slopes which form the banks of the Danube.The elements of the 1st phase are the Danube bridge and two underground motorway junctions, Danube North and South, with excavation cross-sections of up to 375 m2 and the tight radii of the motorway on-ramps. In addition to the elevated location of the main portals, the river Danube, the infrastructure facilities and the built-up area take space in the valley cause unfavourable conditions. Besides these conditions, urban planning requirements have an effect on the realization of the construction project. The excavated material from the tunnel is transported off-site by ship. The project conditions such as the high number of portals, the noise-reflecting effect of the “Danube gorge” and the low overburden require substantial measures to limit and monitor the immissions. x | |||||
Radon i , Nedim; Vesely, Jan | Urban Swedish tunnelling practice - Middle European designer's perspective / Die schwedische innerstädtische Tunnelbaupraxis aus der Sicht eines mitteleuropäischen Planers | Geomechanics and Tunnelling | 5/2021 | 468-476 | Topics |
KurzfassungAmberg Engineering was involved in numerous subsurface infrastructure projects in Sweden, predominantly in the Stockholm metropolitan area. Our rock mechanical and engineering expertise represented and represents our key contribution to the projects, while we came in touch with valuable, and sometimes very different tunnelling approaches. While certain technical solutions still appear exotic, majority of them have to be valued as correct and consequent answers to the predominant geological conditions in Scandinavia. The present publication will show our experience based on one case study. Special attention is given to rock mass characterisation, design processes and tunnelling philosophy. The issues of support, water ingress control and vibration control are treated in detail, and a comparison with our local practice is presented. The paper attempts to deliver an objective treatise and honest presentation of our experience, and a summary of “lessons learned”. x | |||||
Suchmann, Christoph; Fuchs, Christian | Intersection U2xU5 - Tunnelling works at the lot U2/22 / Linienkreuz U2xU5 - Tunnelbaumaßnahmen am Bauabschnitt U2/22 | Geomechanics and Tunnelling | 5/2021 | 477-488 | Topics |
KurzfassungThe next expansion phase of the U2xU5 intersection is currently under construction in the inner districts of the City of Vienna. The construction lot U2/22 Rathaus (City Hall) takes place in the inner districts 1, 7 and 8. Three shafts are the main focus of the construction works at Friedrich-Schmidt-Platz, directly behind the Vienna City Hall as well as a shaft with extensive works on the building of the University of Vienna and another shaft at Josefstädter Straße. Due to difficult and changing geology, different support measures from full face tunnel excavation to tunnelling under a roof of jet grouting piles will be used. In addition, measures such as groundwater drainage, structural improvements of buildings and settlement compensations are necessary in advance. x | |||||
Hochart, Arnaud; Vialle, Denis | Innovative slurry solutions for demanding TBM drives through soil with high permeability in a dense urban area | Geomechanics and Tunnelling | 5/2021 | 489-500 | Topics |
KurzfassungThe extension of the Metro B line in Lyon represents a technical challenge combining difficulties with very few equivalents in pressurised TBM history. Alluviums with wide porosity and high permeability (up to 10-2 m/s) imply a risk of slurry loss leading to ground instabilities. To mitigate geological risks without using heavy ground treatment, two lines of research were followed: x | |||||
Schröfelbauer, Thomas; Permanschlager, Katrin; Montag, Oliver; Avender, Thomas | S1 Tunnel Donau-Lobau - The complex path to geological exploration in the Donau-Auen National Park / S1 Tunnel Donau-Lobau - Der komplexe Weg zur Baugrunderkundung im Nationalpark Donau-Auen | Geomechanics and Tunnelling | 5/2021 | 501-509 | Topics |
KurzfassungThe S1 Donau-Lobau tunnel closes the gap in the road network around Vienna. Its two tunnel tubes run under the Danube and the Donau-Auen National Park, with the provision that no work is allowed to take place on the surface of the site. The (hydro-)geological subsurface conditions in the project area can be described as “difficult”. The tunnel project must also meet all safety-related requirements that arise during construction and operation, while at the same time minimizing the environmental impact. x | |||||
Gächter, Werner; Exenberger, Hans; Fasching, Alfred; Hillisch, Stefan; Mulitzer, Günther; Seywald, Martin; Rettenbacher, Martin; Fröch, Georg; Flora, Matthias | Possible applications for a digital ground model in infrastructure construction / Anwendungsmöglichkeiten eines digitalen Baugrundmodells im Infrastrukturbau | Geomechanics and Tunnelling | 5/2021 | 510-520 | Topics |
KurzfassungThe BIM pilot project “New Köstendorf-Salzburg Line” for ÖBB-Infrastruktur AG covers a new twin-track section about 21 km long involving a wide variety of different engineering structures and a corresponding need for close interdisciplinary collaboration within a sensitive project space. The pilot project successfully achieved its objective of generating a largely software-independent overall model and transferring the knowledge gained to the Employer's Information Requirements and subsequently to a BIM execution plan. In addition to internal coordination meetings, a preliminary external meeting took place to discuss the model elements required for a government agency as part of an approval process and the availability of such elements by means of direct access to the model. x | |||||
Mesic, Muhamed | New insights into the contractual subsoil risk - A view beyond the Austrian horizon / Neues zum Baugrundrisiko - Ein Blick über den Tellerrand | Geomechanics and Tunnelling | 5/2021 | 522-528 | Topics |
KurzfassungDifferent approaches have emerged in dealing with the subject of subsoil risk over the last 25 years. The complex area of geotechnical engineering has contributed significantly to the problem through the development of new technologies. A contractually correct “absorption” of the external conditions has thus become an increasing challenge. This paper describes some of the more recent developments on the subsoil risk, not least in the delimitation to other contractual risks and the contractual arrangement of risk allocation. The topic has also provided for interesting approaches outside Austria, which are also discussed here. The aim is to provide new impulses for dealing with the subsoil risk. x | |||||
Purrer, Walter | Dispute adjudication in Austrian conditions of contract for underground works / Der TSV im Spannungsfeld von Baugrundrisiko und Sphärentrennung | Geomechanics and Tunnelling | 5/2021 | 529-536 | Topics |
KurzfassungThe institution of a neutral Tunnelling Expert (TE) has proven to be of benefit to Austrian Tunnelling Projects. However, misdevelopments have been observed during recent years, which lead to setbacks and obstructions against utilizing its full potential. On the basis of practical experiences, the reasons and backgrounds are explained and options for improved collaboration of the participants by targeted involvement of the TE are shown. These considerations are not restricted to structural topics. They also take into account the mechanism of the social system of manpower cooperating in construction projects, x | |||||
Weh, Markus | Dealing with geological risk in Switzerland - Mix shield TBM on the Eppenberg tunnel site, field report / Umgang mit dem Baugrundrisiko in der Schweiz, Erfahrungsbericht zum Vortrieb einer Mix-Schild-TBM auf der Baustelle Eppenbergtunnel | Geomechanics and Tunnelling | 5/2021 | 537-546 | Topics |
KurzfassungOn the mix-shield TBM excavation of the Eppenberg tunnel, unexpected conditions were encountered in both the rock and soil excavations, which resulted in a modified execution of the project. In this case, the openly formulated contract made it possible to take advantage of improvements in the ground and to manage unexpected system behaviour with the right measures in such a way that economical and time-saving excavation was possible. In all three examples presented in this paper, time is one of the key success factors, because recurring processes result in feedback processes that change the system behaviour more and more rapidly as time goes on. In order to reduce the resulting additional costs and time losses, it is necessary to understand what is happening on site, then evaluate, test and check the possible measures, and finally decide on their implementation in a timely manner. At Eppenberg tunnel, this enabled unexpectedly adverse system behaviour to be overcome in two cases without any major loss of construction time. This was only possible because the responsible persons from all parties involved were able to discuss the situation together and make decisions at short notice. x | |||||
Sellner, Peter Johann; Pacher, Wolfgang; Weinmar, Wolfgang; Moser, Herwig; Monsberger, Yvonne | Impact of alternative tunnelling procedure on contractual allocation of ground risk at S 7 motorway Tunnel Project Rudersdorf / Alternatives Vortriebskonzept - Verlagerung des Baugrundrisikos beim Tunnel Rudersdorf | Geomechanics and Tunnelling | 5/2021 | 547-556 | Topics |
KurzfassungThe approx. 3 km long twin-tube Rudersdorf tunnel is part of the Fürstenfeld Motorway S7. In addition to jet grouting and steel pipe umbrella sections, the excavation is mainly carried out according to the NATM. After the contract had been signed, the contractor proposed a value engineering concept including a stepped (almost) full excavation with a short ring closure. This concept avoids jet grouting sections and reduces sections with steel pipe umbrellas and the temporary top heading invert. A fair risk transfer between both contractual partner enables the full technical and economic potential of the project to be released and guarantees a win-win situation. The modified construction methodology consequently also requires a change of tasks and responsibility for the contractual partners for the project. This paper highlights the main topics of the contractual modifications required and explains the handling of the ground risk with examples. x | |||||
Steiner, Walter | Geotechnical processes at the tunnel face - The key to successful tunnelling / Erkennen geotechnischer Vorgänge an der Ortsbrust als Schlüssel zum erfolgreichen Tunnelvortrieb | Geomechanics and Tunnelling | 5/2021 | 557-568 | Topics |
KurzfassungWhen tunnelling with a TBM (Tunnel Boring Machine) in rock and soil, mostly the machine is described and often reduced to a slogan. Such descriptions say little about geotechnical processes at the tunnel face that are key to the success of tunnel driving and must be considered when selecting a tunnelling system. In soil tunnels the tunnel face must be safely supported and extracting material must be possible. For a slurry shield the slurry must not escape and pressure must act on the face. In the literature mostly bentonite content is considered. With an Earth-Pressure balance machine the soil has to have characteristics that it can be remoulded and transformed in a mass of adequate consistency with mechanical means, adding water and additives such that this mass can support the face and be extracted. Long-term experience shows that the fine content and polymers are also important factors. Flow channels (pores) in open gravel may be clogged, and the face supported by seepage forces. Also, the drag forces in the slurry circuit are increased and the operation of the slurry circuit became more stable. Rates of advance exceeding 10 m/day were achieved with a 11.6 m slurry shield. The limited depth of penetration of the slurry could be determined in-situ. For fine-grained soils the characteristics of the fines are crucial and are described by the Atterberg limits. Soil mechanics strength properties may be vastly different. x | |||||
Jukes, Simon; Schenk, Stephan | Feeder 9 Gas Pipeline Replacement Tunnel - Achieving a world record for pipe insertion of a new gas pipeline within a tunnel beneath the river Humber (UK) | Geomechanics and Tunnelling | 5/2021 | 569-573 | Topics |
KurzfassungSince December 2020, at a pressure of 70 bar, up to 25 % of Britain's gas requirements was flowing through the new Feeder 9 gas pipeline, which installed in a 4.9 km long tunnel 30 m below the River Humber. With the insertion of the new pipeline, the Humber Pipeline Joint Venture (HPT JV), consisting of the companies Porr, Skanska and A. Hak, achieved a major milestone when it was officially recognised as a Guinness World Record for the longest hydraulically-inserted pipe at 4,963.7 m long. Replacing the existing pipeline was an absolute necessity due to the shifting river bed which, over the years, had exposed sections of the pipeline threatening the supply to the customers in the UK. The solution adopted by the client, National Grid to provide a long-term permanent solution, was for the construction of a segmental lined tunnel with an inner diameter of 3.65 m accommodating the new 1050 mm diameter welded steel gas pipe. The tunnel was excavated with a 4.4 m diameter mix shield type TBM. The small diameter together with the length, without intermediate access including a tidal range in the Humber estuary of up to 6.4 m and an overburden on the tunnel of 10 m below the river bed resulted in a number of challenges. The installation of the concrete-coated steel pipeline was particularly high risk. The individual strings ranging from 595 to 620 m in length and weighing about 850 t, were pushed consecutively into the water-filled tunnel employing two hydraulic thrusters in just 18 days. x | |||||
Bäppler, Karin; Battistoni, Frédéric; Burger, Werner; Flora, Matthias; Schwärzel, Matthias | Initial project experiences with variable density TBMs in Europa - Extension of the Lyon metro line B / Erste Projekterfahrungen mit Variable-Density-TVMs in Europa - Erweiterung der U-Bahnlinie B in Lyon | Geomechanics and Tunnelling | 5/2021 | 574-583 | Topics |
KurzfassungGlobalisation and advancing urbanisation around the globe have a significant influence on market dynamics in tunnelling. The expansion of infrastructures in urban and regional centres calls for the construction of new transport, supply, and disposal systems to link individual economic centres. Innovative technologies in mechanised tunnelling, such as the now well-established Variable Density TBM, are making a significant contribution to the safe and low-settlement construction of sustainable tunnel infrastructure projects in extremely challenging and variable ground conditions. In this publication, the current developments and design features as well as the application areas of the Variable Density Technology are addressed, based on one of the first project experiences in Europe, in Lyon. x | |||||
Tintelnot, Götz; Koch, Michael | Injection materials in tunnel excavation material - Waste or substitute construction material? / Injektionsstoffe im Tunnelausbruchmaterial - Abfall oder Ersatzbaustoff? | Geomechanics and Tunnelling | 5/2021 | 584-591 | Topics |
KurzfassungThis paper examines the possibility of using excavated material with system-related admixtures as a substitute construction material, considering the current rules and regulations in the field of landfilling or disposal. In addition to conventional injections with bentonite- and cement-containing suspensions, which always require longer setting times and are relevant for classification during disposal with sulfate values in the eluate, fast-setting multicomponent resins are suitable for filling or consolidation, e.g. fast-reacting, high-foaming silicate resins, polyurethane resins for stopping water ingress, or rubber-elastic, versatile 3-component acrylate gels. However, the discussion is currently focusing on tunnelling compounds to which foams or resins have been added and which, according to Systal's “system-related admixtures”, are to be remunerated as special services. This paper deals with the question how to deal with the excavated material contaminated with organic matter under soil protection law and waste law. On the basis of the results of laboratory tests, the question arises as to whether tunnel excavation with a few percent of organic, system-related admixtures would not make an excellent substitute building material in the sense of the draft substitute building materials ordinance. x | |||||
Flora, Matthias; Weiser, Torsten; Zech, Philipp; Ruepp, Anna; Bergmeister, Konrad | Added value in mechanized tunnelling by intelligent systems / Mehrwerte im maschinellen Tunnelvortrieb durch intelligente Systeme | Geomechanics and Tunnelling | 5/2021 | 592-599 | Topics |
KurzfassungBoth conventional and mechanized tunnelling have a fantastic tradition. The technical progress of the industry moved in step with social developments, characterized by crises and leaps in innovation. In the field of mechanized tunnelling, the driving force for some years now has been the desire to excavate heterogeneous construction sites with changes in tunnelling modes without the need for costly conversions underground. In addition, two innovation surges are currently discernible. On the one hand, the demands on innovation and technology management again follow a societal challenge, namely the goal of climate neutrality. On the other hand, digital processes and tools are changing all areas of our lives at an enormous speed, which means that the construction industry will also undergo a transformation in the coming years. Automation, robotics, the Internet of Things, machine learning, or artificial intelligence are all gradually encroaching on current processes and methods. x | |||||
Türtscher, Matthias; Mark, Simon; Leitner, Wolfgang; Innerhofer, Guntram | "Flying" start with gripper TBM in flat and inclined shaft / "Fliegendes" Andrehen mit einer Gripper-TBM in Flach- und Steilstrecke | Geomechanics and Tunnelling | 5/2021 | 600-608 | Topics |
KurzfassungContractor G. Hinteregger & Söhne Baugesellschaft mbH submitted an alternative proposal for the “Rodundwerk I, new headrace and distribution pipe system” project commissioned by Illwerke vkw AG which uses a new launch structure for an open gripper TBM. An Austrian utility model has been registered for this new development. This paper describes the process. x | |||||
Dickmann, Thomas; Hecht-Méndez, Jozsef; Krüger, Dirk; Sapronova, Alla; Unterlaß, Paul Johannes; Marcher, Thomas | Towards the integration of smart techniques for tunnel seismic applications | Geomechanics and Tunnelling | 5/2021 | 609-615 | Topics |
KurzfassungApplications of seismic measurements for the prediction of hazard zones are applied practice in many tunnel drives in rock mass today. Next to a large exploration range and accurate localisation of discontinuities, seismic data provide attributes for a comprehensive characterisation of the ground conditions. A good synchronisation of all technical components is required to obtain optimum data quality and quantity while the tunnel excavation is not obstructed thereby. Firstly, the signal source must feed as much energy as possible into the rock in a very short time. Secondly, continuity of the signal generation with constant quality and its precise timing by means of wireless data transmission also ensure a reliable measurement process. Artificial intelligence is used to determine the quality of the recorded data already in the tunnel and feedback is given to the user keeping the data quality high. From the tunnel site, recorded raw data can be transferred to a cloud, from where an authorised processor collects them, wherever in the world. An immediately started data processing delivers a result within an hour that includes a geological forecast of up to 150 m of heading, depending on the rock mass condition. In addition to data quality, the quality of the results is crucial. Therefore, techniques are currently under development using machine learning to correlate and analyse seismic attributes with geological properties. This should lead to a more objective evaluation of the geological forecast in the future. x | |||||
Chwatal, Werner; Domenig, Angela; Kostial, Dieter; Rudel, Thomas; Schlögel, Günter; Wagner, Hanns | Review of the "Tunnel Seismic While Drilling" measurements during construction of the Koralm Tunnel at section KAT2 / Erkenntnisse aus den "Tunnel Seismic While Drilling" Messungen während des Vortriebs am Koralmtunnel Baulos KAT2 | Geomechanics and Tunnelling | 5/2021 | 616-625 | Topics |
KurzfassungThe 32.9 km long Koralm tunnel (Austria) is the core piece of the Koralm railway and will be one of the longest railway tunnels worldwide after completion. At the longest construction section “KAT2” two approx. 17 km long parallel single-track tunnels were driven by two double-shield tunnel boring machines with a diameter of about 10 m. Accompanying the tunnelling of the two tubes, the continuous Tunnel Seismic While Drilling (TSWD) method was used shortly after the start of mechanical excavation in January 2013 until the final position was reached in February 2018. The aim was to consistently explore the rock mass up to 100 m in front of the tunnel face to detect faults and water-bearing zones which were relevant for tunnel construction. Another purpose of the measurements was to reduce the number of exploration drillings ahead of the tunnel face. After an initial test phase of about 5000 m, where exploration drillings were continuously carried out parallel with TSWD, an advanced and optimized exploration concept was evaluated and performed for permanent operation. This paper summarizes the findings gained from the TSWD measurements at this tunnel site. x | |||||
Kratz, Thorsten; Vogel, Guido; Ouschan, Michael | Combined exploration drilling with digital data management / Einsatz kombinierter Bohrverfahren zur Vorauserkundung mit digitalem Bohrdatenmanagement | Geomechanics and Tunnelling | 5/2021 | 626-636 | Topics |
KurzfassungThe purpose of exploration drillings in tunnelling operations is to investigate rock structure, geological composition of the rock, especially with regard to fault zones, and the identification and characterisation of water-bearing zones. When determining the quality of exploration, the economic parameters must be taken into account. The application of combined exploration drilling methods allows the successful drilling of exploration drillings even in complex geotechnical and hydrogeological rock conditions. The concept provides the flexibility to switch between drilling systems and to realise probe measures tailored to the specific geology quickly and according to economic requirements. For successful exploration projects, documents and findings from past projects are used in the planning phase. The use of digital drilling data management offers enormous potential for optimising data evaluation. The determination of machine, equipment and the preparation of a drilling plan can thus be prepared much more specifically for the upcoming exploration. During execution, direct conclusions can be reached regarding e.g. drillability or drilling tool condition on the basis of the process-oriented process analysis. x | |||||
Schmidt, Markus; Zenz, Reinhard; Richter, Thomas | Innovative geophysical exploration technologies in karst-prone and crystalline rock formations / Innovative geophysikalische Vorauserkundungstechnologie in verkarstungsfähigen und kristallinen Gesteinen | Geomechanics and Tunnelling | 5/2021 | 637-652 | Topics |
KurzfassungIn rock formations prone to karstification there are only limited geological/hydrological principles that allow a safe prognosis of the existence and location of karstic and fault structures. A combination of geophysical borehole radar measurements utilizing both reflection and crosshole probe setups can be used to reliably detect anomalous structures, especially air-filled karstic cavities and fault zones, when a sensible measuring concept for karstified or crystalline rocks is applied. Besides the determination of the anomalous structure's location it is also possible to distinguish its type of filling. Using examples from the major railway project Albaufstieg between Wendlingen-Ulm the investigation concepts ahead of the tunnel construction are presented. The borehole radar measurements were successfully utilized during different phases of the tunnel excavation and could be integrated into the construction process without significant delays, thus contributing to a safe construction process and later operation of the tunnels. The reliability and high efficiency of these borehole radar investigation concepts places this technology of karst detection at a significant advantage over the commonly applied seismic methods, especially in karst-prone and crystalline rocks. x |