STUVA’s International Forum for Tunnels and Infrastructure was held in the tradition-steeped Dortmund Westfalenhallen from December 1 to 3, 2015. The outcome was highly impressive – the figures alone speak for themselves, establishing various new records for the STUVA Conference: more than 1800 conference participants and 165 exhibiting companies from the tunnel industry spread over around 6000 m² of display area. However, there was more to it than just records for a genuine innovation was introduced – quite apart from the novelties shown by the exhibiting firms: in addition to the subject area “Tunnelling”, “Tunnel Operation” was integrated in the STUVA Conference for the first time as a new segment with its own two-day long parallel series of lectures. At the same time, something was still preserved as it always was: that really special STUVA Conference feeling!
On December 1, 2015 at 8.00 am on the dot the doors of the Westfalenhallen opened to offer the record number of 1850 tunnelling experts a programme, unparalleled in terms of concentration and diversity. STUVA’s International Forum for Tunnels and Infrastructure, which is held every two years, has gradually developed into one of the most significant gatherings for underground construction and mobility. The grand lecture hall was practically chock-a-block for the opening papers; this year participants from 26 countries attended the STUVA Conference. First of all, STUVA board chairman Univ.-Prof. Dr.-Ing. Martin Ziegler welcomed the conference participants and laid out the current status of tunnelling and the likely perspectives for the future. “Modern society lives from mobility and a functioning infrastructure. And both depend on underground construction,” Ziegler concluded. Apart from new projects, the years ahead will witness more attention than ever being paid to upgrading and redeveloping existing tunnels. “In some cases, we’re travelling through tunnels that are well over 100 years old,” Ziegler emphasized.
In the process, not only the redevelopment of structures is at stake, operational and safety-technical demands must also be addressed. “We must on no account wait, as was the cases with bridges, until we have to close individual tunnels for safety reasons”. As the topic of tunnel operation and safety has taken on such enormous importance, the STUVA decided to introduce a new segment on “Tunnel Operation” at the STUVA Conference.
There was good reason why the 2015 STUVA Conference took place in Dortmund. With the restructuring of the Emscher, Dortmund along with many other towns in the northern Ruhr District is currently experiencing Europe’s largest infrastructural project. Accordingly, Dortmund’s mayor Manfred Sauer referred to the significance of the Emscher project in his welcoming address for urban development in Dortmund and all the other communities in the region. For almost a century, the technically developed Emscher and its dead straight tributaries characterized the region. As with the end of coal mining no more mining subsidence of a serious nature is to be anticipated, waste water can now be passed through underground conduits. Nowadays, you rarely encounter such water openly flowing through built-up areas. The Emscher Valley also saw itself faced with these options albeit involuntarily. The water can be reclaimed for nature and the landscape and as an enriching element in the city. In the related keynote speech, delivered by Dr. Mario Sommerhäuser on behalf of the Emschergenossenschaft CEO, Dr. Jochen Stemplewski, the construction activities that have now lasted all of twenty years, were presented in detail. When the project is completed in 2017, 400 km of sewers will have been reconstructed and 120 km of the river course renaturalized. The total investment volume will amount to around 4.5 billion euros. According to Dr. Sommerhäuser many factors account for such a transformation taking place in one of Europe’s most densely populated regions. Among them the Emscher Master Plan devised in 2006, which is regarded as the guiding principle for the spatial, urban and rural development of the new Emscher Valley, coordinates the numerous part-projects. Without modern engineering methods like trenchless pipe jacking such a project would be inconceivable in Europe’s biggest built-up area.
In a further keynote address Prof. Dirk Rompf, board member responsible for network planning and major projects with the DB Netz AG, provided an overview of major projects planned by the Deutsche Bahn. As first and foremost the big cities are registering over-average growth in Germany, rail transportation between major centres is also growing at an over-average pace. With its network conception 2030, the Deutsche Bahn AG is preparing for an increase in passenger km of 23 % and as much as 42 % growth for goods traffic on rail. The three biggest DB projects for the next five years are all geared to this trend: the German Unity Transport Project between Leipzig and Nuremberg just as the two new/upgraded routes between Stuttgart and Ulm and Karlsruhe and Basle. In this connection, the DB has also recognized that major projects can only be executed providing they are largely accepted by the general public. “Infrastructure projects must not simply fulfil functional, technical, economic and legal criteria, they also must be borne by the citizens,” Rompf believes. As a result, the DB intends investing in ensuring the public takes part at an earlier stage and to communicate in a better manner.
Following the opening papers, the STUVA Conference split into two separate parallel series of lectures for the very first time. Consequently, more than 60 papers were presented, 25 of which were delivered in the new “Tunnel Operation” segment. The forenoon of the first day of the Tunnelling segment was devoted to exciting international major projects. Dipl.-Ing. Rainer Rengshausen from Porr Tunnelbau reported on his experiences under highly tricky climatic and geological conditions while building the Doha Green Line of the Metro in Qatar, driven by six TBMs. Heinz Ehrbar, who is in charge of managing major projects on behalf of the DB AG, discussed the suitable choice of systems for long rail tunnels. Claus Iversen, construction manager of the Femern A/S in Copenhagen provided an overview of progress made in designing the Fehmarn Belt immersed tunnel, and Brian Fulcher as responsible tunnel division manager gave interesting impressions of building the New York Second Avenue Subway. Tim Babendererde opened the “mechanized tunnelling” block of topics with a paper on the application of sprayable membranes and synthetic soils to free blocked tunnelling machines from the extraction chamber. Then, Dr.-Ing. Bertram Ostermeier, managing partner of PSP Consulting Engineers GmbH spoke of findings made during the building of seven cross-passages in the Slowacki Tunnel in Danzig. For this purpose, special segments and extensive ground freezing were applied. Subsequently, Dipl.-Ing. Frank Nenninger as authorized representative of the KASIG summarized the requirements for plan approval, design, tendering, execution and measurement technical monitoring for the Karlsruhe Combined Solution project, prior to Univ.-Prof. Dr.-Ing. Markus Thewes from the Bochum Ruhr University dealing with the significance of process simulation for planning and performance analysis of mechanized tunnel drives. Dr.-Ing. Janosch Stascheit, Maidl Tunnelconsultants, examined new recognitions on control accuracy of support pressure for shield driving with active face support taking topical case examples. Then Dr. Karin Bäppler from the Herrenknecht AG rounded off the first day of the Tunnelling segment with her paper devoted to altering the application limits of mix-shields.
The first series of papers of the new Tunnel Operation segment opened in the second conference hall to coincide with the tunnellers’ session. In the first block “Future Perspectives” first of all, Dr.-Ing. Gero Marzahn, responsible for bridges, tunnels and other engineering structures at the Federal Ministry of Transport and Digital Infrastructure (BMVI), reported on the retrofitting programme for road tunnels and the necessary measures to assure the greatest possible availability of tunnels for users. Subsequently, Dr. Lutz Rittershaus from the department for cooperative traffic and driver assistance systems at the Federal Highway Research Institute (BASt) then addressed networked mobility and future infrastructures. Dr. Renzo Simoni, the CEO of the AlpTransit Gotthard AG explained the approach adopted in making the Gotthard Base Tunnel, the world’s longest rail tunnel, operational. Subsequently, Prof. Dr.-Ing. Wolfgang Baltzer, who chairs the RABT Committee, provided an overview of the many new aspects contained in the revised “Guidelines for Furnishing and Operating Road Tunnels (RABT), due to be published shortly. The afternoon for the “tunnel operators” was given over to no less than six papers dealing with operational safety: considerations for avoiding congestion by temporarily opening up emergency lanes in tunnels, initial experiences with implementing a real-time safety management system (ESIMAS) for tunnel monitoring, measures to manage control technology in road tunnels, safety issues when applying open-pored asphalt in enclosures and road tunnels, intelligent induction loops for automatically detecting incidents in road tunnels and the validation and verification process from design to opening for the Spaarndammer Tunnel, Amsterdam. Just like the parallel series of lectures provided for tunnellers, the afternoon block wound up at 4.15 pm so that all conference participants could attend the STUVA competition for up-and-comers in the "Youth Forum", either as members of the audience or jurors.
165 exhibitors set up an exciting and diversified fairscape over more than 2600 m² of rented space. Both exhibition days were well attended – with the stands in some cases being swamped with visitors – not just during the conference breaks but almost without interruption. Furthermore, around 500 exhibition visitors also turned up in addition to the registered conference participants, who had been attracted by the prospect of attending the exhibition free of charge. Both the exhibitors as well as the trade visitors are unanimous: the STUVA Conference combined with such an extensive accompanying fair is the ideal location for presenting one’s own products, refreshing existing business contacts, establishing new ones or simply looking beyond the rim.
Undoubtedly the festive evening represents a highlight of every STUVA Conference. This time around it was held in the mighty oval formed by Westfalenhalle 1, a true Dortmund landmark. In a delightful atmosphere, the participants were able to consolidate existing contacts and establish new ones. The artistic performance of the two artistes at a dizzying height provided the evening with a particular flair. As in previous years, the official end of the gala evening certainly did not mean at all that the day itself was over. The Keller Grundbau Company once again set up their “Kellerbar” and displayed what good construction logisticians are capable of in terms of handling barrels of beer. There was free beer for all until the wee small hours and a “currywurst” sausage to still anyone’s hunger around midnight.
In the early part of the second day, the tunnellers tackled a whole series of topics devoted to combined construction methods, construction technology and legal issues as well as safety in tunnels. The tunnel operation segment at the same time was preoccupied with the fields of “personal security” and “rehabilitation and maintenance”. In the afternoon, the tunnellers concentrated on “conversion and redevelopment”, whereas the tunnel operation segment examined fire protection issues and ventilation. Unfortunately there’s not enough space available here to do justice to all the interesting topics. As a result, whoever is interested is advised to follow up by perusing the Proceedings. With more than 400 pages, it’s a real record breaking read. Both series of lectures finished at 4.00 pm so that all those taking part were in a position to turn up at the closing session “Underground Construction in Dortmund”. In their papers, the four lecturers in the closing block provided a comprehensive picture of the major Emscher rehabilitation project. Dipl.-Ing. Reinhard Ketteler reported on the special aspects of technology and logistics during the parallel excavation of small tunnels by shield driving and Dipl.-Geol. Markus Kühnel dealt with special features when producing the huge circular diaphragm wall excavation pit for the Oberhausen pumping station for the Emscher Interceptor. Dipl.-Ing. Gerd Martini concentrated on the development of quality demands for reinforced concrete for pipes, segments and in situ concrete structures. The 2015 STUVA Conference’s final lecture was presented by Dipl.-Ing. Christian Strasser, who summarized the findings obtained from planning and executing 50 km of pipe jacking for the Interceptor project.
The third day of the STUVA Conference was given over to excursions as has always been the case. These are undertaken in small groups headed by experts. The Emscher redevelopment scheme with its numerous interventions in the underground of the northern Ruhr District was of course the main topic. In fact, several excursion groups were given a thorough insight into this mega project by the Emschergenossenschaft. However, diverse excursions such as to the site for the Dortmund light rail system station at the Central Station, to the new Lennetal Bridge on the A45 or a works visit to ThyssenKrupp were also on the programme as well as opportunities to look at the North-South light rail system in Cologne or the site for the Wehrhahn Line in Düsseldorf. Certainly, descending into one of the two last active coal mines in Germany – “Prosper-Haniel” – represented a real highlight. The STUVA Conference participants, who were fortunate enough to secure a ticket for this excursion in time, are numbered among the last people able to experience a German coal mine in operation. For Prosper-Haniel will close down completely in 2018 thus finally bringing to an end the long-standing tradition of hard coal mining in Germany.
When there’s one down, there’s always another to go! As was also the case in 2013, the STUVA Conference will again be held in Stuttgart, from December 6–8, 2017. The amount of progress achieved by “Stuttgart–Ulm”, Germany’s biggest rail project at present, will once again provide the exciting backdrop for the No. 1 conference dealing with underground construction. It’s certainly well worthwhile occasionally referring to www. stuva-conference.com to stay abreast of how the preparations for the 2017 STUVA Conference are advancing. Anyone interested in being present with an exhibition booth at the “tunnellers’ family gathering” should not hesitate. Make sure you register so that you receive all the necessary details for signing up. Start of registration will probably be in November 2016. Heiko Heiden, the CEO of Deltacom Projektmanagement GmbH, is now available as your competent contact partner for the STUVA-Expo (tel.: +49 40 357232-0; firstname.lastname@example.org). For this time, the STUVA team would finally like to express its sincere thanks to all the lecturers, participants, exhibitors, sponsors and trade visitors. Without your involvement, the STUVA Conference would not be what it is. For the time being, all the best and see you in two years’ time!