A European partnership to improve safety

Mobility of people and reliable transport of goods are key issues in our society. Economic growth and societal development rely heavily upon safe and secure infrastructure, in which road, rail and metro tunnels and other covered infrastructure are important elements.

In the aftermath of major disasters in Europe in the last decade, extensive research activity has started (see article from Dimitrios Theologitis, Intelligent Transport issue 3 2005). In this article some specific findings will be highlighted, resulting from two major EU co-financed projects: UPTUN and L-surF. The article will also draw upon future developments, such as further internationalisation of tunnel fire safety, through the combination of research and development consortia in a new ambitious ITA committee.

The origin of tunnel fire safety problems

To date, tunnels are common elements in the infrastructure we use, often on a daily basis.A large number of the existing tunnels were designed, however, with the knowledge and experience of some decades ago. In the mean time, transport and traffic have grown considerably in volume and have also changed in composition (more combustible and flammable goods). Consequently, the safety level in existing tunnels has decreased in cases where no intermediate measures were taken to cope with the changed type and loading of vehicles and rolling stock. This holds throughout Europe, for road, rail and metro tunnels. It is evident that without any measures of improvement, or upgrading, the actual safety in numerous tunnels no longer complies with the anticipated, desired or required level.

In addition to the increased transport volume, the accidents in recent years have drawn widespread attention to the risk of fires in tunnels. This has two consequences. First, the fires themselves have resulted in fatalities, casualties and/or large direct economic damage. They have also resulted in lengthy shut-downs of the tunnels themselves, yielding high indirect economic losses and adverse effect on (socio-) economic development in areas surrounding the affected tunnels. Secondly, the perceived risk of fire is also likely to have discouraged tunnel usage in some cases (tunnels might become an unwanted impediment for trade). Both of these consequences have contributed to congestion and hence noise and pollution with negative environmental and health consequences. As a result of the accidents, and the media attention they have attracted, the public acceptance level of fires causing major losses has also decreased. Moreover, the need for underground infrastructures will grow because logistics are needed and the surface is quite often not available anymore to be used for these transport needs. So if underground infrastructures will become more important and numerous, the confidence in their safety and security use must be (re-)established.

Partnership in Europe

Although the average end-user experiences a road, rail or metro tunnel as a mere underground tube, tunnels are in fact complex systems. In such a complex system, safety is achieved through a balanced combination of advanced civil engineering construction, installations and operation (including emergency response). In order to design and assess safety in a complex system, a multi-disciplinary holistic approach is necessary, comprising the input and views of all stakeholders and technology involved.

This and the above mentioned problems were recognised by the European Commission and other stakeholders. Throughout Europe, initiatives were taken up and partnerships were created. So-called thematic networks were established with a view to efficiently gather and open up existing information for all involved parties and also research and development projects were started, with a view to foster the necessary innovation.

Upgrading the safety of existing tunnels (UPTUN) One of the research and development projects focused on the upgrading of existing tunnels: UPTUN (an acronym for: Cost-effective, Sustainable and Innovative Upgrading Methods for Fire Safety in Existing Tunnels).

The UPTUN project’s main objectives are:

• Development of innovative technologies where appropriate and where relevant comparing to and the assessment of existing technologies for tunnel application. The main focus is on technologies in the areas of detection and monitoring, mitigating measures, influencing human response, and protection against structural damage. The main output is a set of innovative cost-effective technologies.
• Development, demonstration and promotion of procedures for rational safety level evaluation, including decision support models, and knowledge transfer. The main output is a risk based evaluating and upgrading model.

In order to achieve these objectives, a strong European consortium was needed, covering all relevant expertise, with sufficient mass and impact to ensure adoption of UPTUN deliverables throughout Europe. The consortium was built around the prominent tunnel safety institutes in Europe, balancing owners, industry, research and other stakeholders on the one hand and balancing the EU (tunnel) member states on the other hand.

The UPTUN consortium consists of 42 members from 11 different EU Member States, one EEA Member State and from three accession countries. Furthermore, the consortium comprises industry, research organisations, consultancy companies, owners of tunnels and universities.

The desired spin-off of the project is the restoration of faith in tunnels as safe and reliable parts of the transportation systems, but also the levelling out of trade barriers imposed by supposedly unsafe tunnels, and last but not least, an increased permanent awareness of stakeholders for the necessity to develop initiatives to link all relevant research. It is expected that UPTUN will produce its final findings gathered over the four year elapse time of the project, in the course of 2006, prior to the summer holidays.

UPTUN innovations

In case of an incident, and actually prior to that, the first task is to gather information. Innovations have been developed to detect fire and smoke, and adequately linking the detection to active measures to control smoke development and/or the fire. Furthermore, innovation is also focused on new detection methods for people and for vehicles or rolling stock, both stationary and moving.Any measure on the level of installation or operation (guiding evacuees, emergency response service) should be based on actual information regarding the location (whereabouts: duplication in working) of the fire and the distribution of smoke, its anticipated development based on knowledge of type and mass of the combustibles and the whereabouts of users.Within the UPTUN project a comprehensive effort is undertaken to gather and adequately link this information for further decision support. The main aim is to reliably detect fire and smoke within 2-5 minutes, because of the likelihood of fire scenarios with rapid developing fires.

Fires can probably never be completely excluded in daily operation. Mitigation measures are therefore inevitable. To date, safety designs rely on well developed ventilation systems for smoke control and passive fire protection through thermal barrier systems with a view to limit damage to the structure. Innovation in this field has focused on other measures, with respect to smoke compartmentalisation and fire growth limitation. Extensive tests have revealed promising results for water-curtains and to a certain degree also for inflatable plugs to control smoke spread as well as for water-mist suppression systems to limit fire growth.

An essential factor in tunnel safety is human behaviour. This counts not only for the users, but also for the operators and emergency response teams. Extensive studies have been performed, using a car and a truck driving simulator. Crowds have been studied in evacuation exercises, innovations were developed to facilitate evacuation (dynamic guidance based on actual temperature and atmosphere monitoring and on the basis of advanced lighting systems combined with sound beacons). Through these innovations, substantial improvement in evacuation can be achieved. Furthermore, concrete results allow for an upgrading of operator rooms and offices. Finally, studies have unravelled the complexity of tasks and interference of emergency response services (medical and fire fighting); concrete recommendations are at hand for finetuning combined operations in the aftermath of incidents.

Once a fire reaches a certain size, without adequate measures, significant damage may occur.With a view to assess the damage level and to quickly and cost-efficiently repair the damage, new computer aided assessment techniques have been developed as well as advanced concrete mixes for repair works. This will allow substantial reduction in non-operational time after an incident.

With a view to assist designers and exploiting institutes or companies, as well as owners of tunnels, an advanced integrated model is being developed, linking technical submodels as well as (socio-) economic models, on the basis of modern and new artificial intelligence computer architecture. The integrated model will allow for easy (geometry and other) data input, facilitating optimised upgrading of a certain specific tunnel, through intelligent and cost-efficient balancing of different (combinations of) safety measures.

Promising demonstration upgrading tests have already been carried in early 2005, amongst others in the upgraded (first bore) Virgolo tunnel in Bolzano, part of the Brenner Highway in Italy.

Currently, extensive knowledge transfer is being developed. For example summer- and other courses are under preparation, to allow the existing as well as the new generation of tunnel safety involved parties to profit from the UPTUN findings. In the autumn of next year, a first full extensive course will be launched.

Large scale problems (L-surF)

If one thing has become apparent from the EU, co-financed projects such as UPTUN and other projects such as DARTS (Durable And Reliable Tunnel Structures; www.dartsproject.net) and FIT (Fire In Tunnels; www.etnfit.net), it is that accurately assessing the safety level of complex systems such as tunnels on the basis of laboratory tests on sub-systems and single elements, even in combination with advanced modeling techniques (CFD, FEA), is hardly possible. This is due to:

• scale effects
• unexpected (adverse or positive) interaction between (mitigating) measures
• limited (read: costly) options to validate models to realistic scale events
• a lack of understanding or even unknown physical phenomena regarding fire development (spread of fire to other vehicles or rolling stock)

Research on safety and security in enclosed underground spaces is of outstanding importance as current incidents (tunnel fires, terror attacks in metros etc.) have shown. However, currently, the EU competence related to safety and security is largely unstructured, fragmented and mostly national oriented. Missing in particular is a large scale research facility and the coordination and synergy of existing facilities. The necessity for a European wide initiative in these respects was also identified and clearly expressed during the 1st International Symposium on safe and reliable tunnels, held in Prague in February 2004.

Leading (fire) safety, security and tunnel construction institutes in Europe (VSH-CH, STUVA-D, Ineris-F, Sintef/NBL-N, SP-S and TNO-NL) have joined forces to develop a versatile research facility, enabling full scale investigation of (combinations of) safety and security measures, not only for tunnels, but for the full spectrum of underground facilities (parkings, buildings). The consortium studies:

• the constructional lay-out of the research facility, based (if the concept is feasible) on an entirely new concept for easily creating any contours, shapes and sizes of enclosed spaces needed, but also all other aspects like installations, environmental impacts etc. The concept will allow novel approaches to R&D work
• innovative measuring sensors, based on the latest technologies (e.g. nanotechnology) available
• the most urgent research needs
• an integration process for the existing and projected national facilities with their competences and researchers, thus restructuring and improving the relevant EU competence while simultaneously showing ways for using R&D funds more economically

L-surF is also about security (terrorist attacks on underground and/or enclosed spaces, e.g. the recent attacks in London) because there are similarities in the effect (casualties, fire, smoke, lack of orientation, questions of evacuation, safety of construction etc) and the need for large scale testing is also given there. Furthermore, L-surF responds to the European strategic initiative on safety and security; these two facts underline the importance of L-SurF.

In due time, L-surF will bundle the strengths of the initiating partners, providing a full range of services, which besides full scale testing includes training and education. This will also act as an integrating nucleus for pan-European activities on safety and security in underground spaces. Readers are invited to visit the L-surF Web site (www.l-surf.org), with a view to responding to questionnaires regarding the necessity for research in this field and/or to declare interest in participating in some form to the L-surF initiative.

Internationalisation

Transport and reliable infrastructure are global problems. The chairmen and coordinators consortia of the projects mentioned above, together with others, have discussed with ITA and PIARC to establish an international permanent body for addressing safety of underground facilities. As a result, the ITA has adopted the idea and a Committee on Operational Safety of Underground Facilities – COSUF will be officially established in Paris, February 2006, under the chairmanship of Prof. Haack. The scope of the Committee is devoted to safety and security in tunnels and underground facilities in operation. The Committee aims to maintain the existing networks (as established in the EUprojects), to encourage collaboration and to facilitate a worldwide co-operation. It is the Committee’s ambition to contribute to and promote tunnel safety by fostering innovation, raising awareness and to support the development of regulations. The committee will initiate adhoc teams to address issues related to safety, to focus on international research programmes (e.g. 7th Frame Research Programme of the EU and ECTP – European Construction Technology Platform). A Web site, based on the FIT-website with its databases, is being developed.

Thus, tunnel fire safety will be closely monitored and watched, and kept on the agenda of stakeholders, with a view to coordinate efforts, technology, expertise and means for optimum safety of end-users allowing safe and reliable transport of people and goods.