Institut für Verbrennungskraftmaschinen und Thermodynamik Technische Universität Graz Institute of Internal Combustion Engines and Thermodynamics Graz University of Technology th 8 International Conference TUNNEL SAFETY AND VENTILATION - New Developments in Tunnel Safety - 25. - 26. April 2016 Graz University of Technology Redaktion / Editor: P. Sturm / S. Minarik I m p r e s s u m: Verlag der Technischen Universität Graz Technikerstraße 4 A-8010 Graz Tel.: +43 316 873 6157 Fax: +43 316 873 6671 E-Mail: [email protected] UID(VAT) ATU 57477929 Reports of the Institute of Internal Combustion Engines and Thermodynamics, Graz University of Technology, Vol. 100 Herausgeber/Publisher: Univ.-Prof. Dr. H. Eichlseder ISBN: 978-3-85125-464-8 ORGANISATION A.Univ.-Prof. Dr. Peter STURM Tel.: +43/316-873 30200 Mrs. Sabine MINARIK Tel.: +43/316-873 30231 Graz University of Technology Fax.: +43/316-873 10 30231 Institute of Internal Combustion E-Mail: [email protected] Engines and Thermodynamics Homepage: www./ivt.turgraz.at A-8010 Graz, Inffeldgasse 21a, Austria - I - PREFACE Ladies and Gentlemen, Dear Participants, In 2002, the Institute of Internal Combustion Engines and Thermodynamics organized an International Conference on Tunnel Safety and Ventilation. The aim of that conference was to provide a forum for information exchange among operators, users, technicians, scientists and companies involved in the design, construction and equipping of road and rail tunnels. The success of the 2002 conference led to the organization of biennial follow up meetings. Each conference has been accompanied by an exhibition, and each year, like the conference itself, the exhibition has grown. The success of the exhibitions has forced us to leave the confines of our University campus and to move to the roomier facilities of the trade fair centre. Our interests and focus have also changed and this is reflected in our topics. The first conferences were strongly influenced by the tunnel incidents of the late 1990’s and related safety issues. Nowadays road tunnel operation, the conflict between the needs for upgrading existing road tunnels and requirements given in a legal framework dominate. Traffic is increasing, at both a national as well as an international level. Thus, while in densely populated areas there is much greater demand for sub-surface transportation, in rural areas there is an increasing need to upgrade the road infrastructure. The implementation of the EU Directive on the minimum safety requirements for tunnels in the trans-European road network (2004/54/EC) forced many of the tunnel operators to upgrade the existing tunnels. Many of the existing tunnels (i.e. those 20 to 30 years old), are currently being refurbished and upgraded by the addition of a second tunnel tube. The upgrading process as well as the construction of second tubes constitutes a big challenge in practice, as – in contrast to new tunnel construction – several prevailing structures and systems act as constraints and have to be taken into consideration in planning. There is also the additional need to ensure that traffic flow can be maintained throughout the construction period. The question of tunnel safety is a highly controversial field. It is often claimed that several new techniques are now on the market and that these can help improve safety due to quicker and more reliable detection, more efficient installations and/or additional equipment. However, such ‘improvements’ often result in significant increases in complexity, as well as in the cost of operation and maintenance of the new safety equipment. Cost benefit analyses combined with risk assessment studies provide a valuable tool when attempting to deal with questions of safety at an acceptable cost level. The time is now right for us to discuss what safety standards are required in our tunnels and at what price. We hope that the present conference will be of some value in such a discussion. This conference wouldn’t be the “Graz” conference without the related exhibition. Many companies have put a lot of effort into presenting their latest developments and technologies. Conference participants now have the chance to get into contact with leading companies in the electro-mechanical tunnel business, to establish new contacts, and also to strengthen existing ones. 8thInternational Conference ‘Tunnel Safety and Ventilation’ 2016, Graz - II - Another exciting and distinguishing aspect of the “Graz” conference is the accompanying technical visit. Contrary to former events where a life live fire test was performed, this time the construction site of the second bore of the Gleinalm tunnel will be the location for a visit. In fact the conference returns to the location in which in 2002 a test with a water shield installation was performed in order to demonstrate tunnel safety installations. While at that time the tunnel consisted in a single bore with bi-directional traffic, this time we have to see the final construction activities of the second bore, which shall be put in operation in 2017. Many thanks to the tunnel operator ASFiNAG. Special thanks to Mr. Gerhard Ruhdorfer and Mr. Herwig Moser for organizing this visit. We wish to extend a special thank you to our scientific committee for its valuable work in defining the objectives of this conference, and in selecting the presentations. We also extend our professional thanks to the authors for their hard work in preparing abstracts, papers, posters, and of course their presentations. And finally, we wish to offer our sincere thanks to all the people in the background who have been working to ensure that this will be a smooth, enjoyable and effective conference for us all. It is my pleasure to welcome you all on behalf of the conference scientific committee and to wish you all a successful meeting and a sound basis for fertile networking in the future. Peter J. Sturm Graz, April 2016 8thInternational Conference ‘Tunnel Safety and Ventilation’ 2016, Graz - 1 - ON THE ROAD TO SAFER TUNNELS 1F. Zumsteg, 1U. Steinemann, 2M. Eisenlohr 1US+FZ Consulting Engineers, Lenzburg/Wollerau CH 2Swiss Federal Roads Office (FEDRO), Bern CH ABSTRACT The fatal fire events around the turn of the millennium led to the amplified efforts to make tunnels safer. Due to the strong traffic increase and as a result of increased social claims and expectations, the pressure has increased prominently for higher tunnel safety with corresponing bigger investment and maintenance efforts. The legal pressure for the identification of persons responsible for incidents also contributes to it. This is reflected on the extent of the requirements in standards and guidelines and has an effect on the inventiveness of manufacturers and engineers as well as on the complexity of the systems in tunnels. Keywords: tunnel safety, ventilation, complex systems 1. INTRODUCTION With regard to ongoing developments we recapitulate successful innovations of the tunnel equipment with their benefit and cost in this paper as well as illutions and dilusions. It turns out that man as the element of uncertainty often limits the use of the systems. In theory many of the developments are plausible. In reality, however, difficulties lead to necessary modifications and compromises. 2. MEANING OF TECHNICAL ACHIEVEMENTS A topic at this year's SWISSBAU was: Is modern technology our rescue or do we have to rescue ourselves from it? The following examples show that this question also has significance for the tunnel equipment. Besides technology in an incident the often unpredictable human behaviour is decisive for success or failure. 2.1. Fire and smoke detection Thermal detection is the standard of fire identification in many places. Today thermal linear sensors are used in all Swiss tunnels with a length over 600 m. With sufficient temperature or sufficient temperature rise the sensors react quickly and locat a fire exactly. An experience of the years well before 2000 was that the turbidity measurements often detected a fire in the Gotthard road tunnel earlier than the thermal sensor although turbidity sensors were mounted at intervals of more than 1 km. Only in 2005, thus 25 years after the opening of the Gotthard tunnel, the Swiss Federal Roads Office FEDRO published a draft for the guideline Fire Detection [1] which prescribes the smoke detection. Today smoke detectors are used in Switzerland in most tunnels at intervals of 100 m, in special cases even at intervals of 50 m. As engineers we have to ask the question how it was possible that this change was carried out so late. The fact that smoke represents the primary peril for the tunnel users seems obvious today. The specifications in [1], which were accompanied by the further development of smoke detectors led to the euphoric feeling to have solved the problem of the smoke and therefore 8th International Conference ‘Tunnel Safety and Ventilation’ 2016, Graz - 2 - fire detection. There was even the hope to be able to go without supplementary systems. Fortunately such simplifications were not introduced immediately because the real time evaluation of the smoke signals proved to be more complicated than expected. Ventilation systems with point extraction by controllable dampers need a precise indication of the fire location. Otherwise the operation of the exhaust air can endanger the tunnel users additionally by transferring the smoke at remarkable speed through the driving space. Moving and pulsating smoke sources confront the developers of the software with fiddly questions. Moreover, it cannot be excluded that a smoke detector is faulty. Again and again, at the check of the functionality of the systems in the tunnel one discovers new scenarios and sequences which show that a reliable fire locating detection takes its time even with smoke detectors. At a smoke test recently carried out with an initially moving smoke source we had to notice that the automatic ventilation mode yielded a place discrepancy between fire place and location of detection of 300 m.