Current safety issues in traffic tunnels

doi:10.1016/S0886-7798(02)00013-5

Tunnelling and Underground Space Technology

Volume 17, Issue 2, April 2002, Pages 117-127

https://doi.org/10.1016/S0886-7798(02)00013-5 Get rights and content

Abstract

In addition to the manner in which tunnels are furnished, improved control of the state of vehicles and the composition of their loads could have better safety standards in traffic tunnels. Joint efforts are imperative to arrive at enhanced and harmonised standards throughout Europe.

Section snippets

Starting situation

A modern industrial society requires an efficient and reliable transportation infrastructure. This applies to road as well as rail. This becomes evident from the BMVBW statistics applying to Germany alone (Table 1, Table 2).

In 1997, some 626 000 km of roads of varying categories were available for road traffic (Table 3). The German rail network, on the other hand, amounts to roughly 44 000 km (without connecting systems or trams, industrial and works railways). Some 40 000 of this total is

Recent fire accidents

Fire incidents in tunnels immediately catch the public's attention and this is quite natural. The media report at length, in particular when people come to harm. The disastrous London Underground fire at the Kings Cross Underground station in November 1987, which cost 31 people their lives, and the catastrophic outcome of the Baku Underground fire (Azerbaijan) in October 1995, resulting in 289 deaths, are mentioned as examples. The Channel Tunnel fire between the UK and France on 18 November,

Accident statistics

Against the background of these serious fire incidents, the issue of vehicle fire frequencies and the attached risks is inevitably raised. The following data and assessments provide a relevant overview. First of all, vehicle fires in general, and not simply those in tunnels, are dealt with.

The following two examples from Germany reveal that a vehicle fire incident is not at all rare. For instance, over the past 10 years in Dortmund (about half a million inhabitants), an average of 250 vehicle

The effects of fire

In the early 1980s, STUVA undertook far-reaching investigations at the behest of the Federal Transport Ministry designed to improve fire protection in tunnels for Underground, urban and tram railways (Heffels et al., 1984), which resulted in important recognitions. They were, by and large, confirmed through major fire tests in Norway within the framework of the Eureka research project (Haack, 1996, Brände in Verkehrstunneln, 1998) and can thus still be regarded as valid today:

a
As far as the

Fire protection measures

As a result of the recent fire disasters, experts are discussing issues relating to the basic appraisal of existing safety standards in tunnels. At stake are preventative constructional as well as operational protection measures together with those designed to combat fire.

Preventative constructional measures initially embrace the choice of suitable materials to be used. In this regard, concrete can be classified as a material with a high fire safety factor. It in no way contributes to the fire

How to behave

Should a fire occur in a tunnel, the situation is definitely far worse than out in the open. Escape and rescue possibilities are restricted in terms of the geometry. However, rapidly rising heat radiation, the fast release of fire gases and a related decrease in visibility, above all, form potential risks (Fig. 9). The fact that many motorists misinterpreted this situation during the Mont Blanc Tunnel fire largely contributed to its catastrophic outcome. Against this background, it is essential

Considerations pertaining to the design of future traffic tunnels

The recent fire incidents touched on earlier have triggered an intensive debate among the general public (ADAC-Motorwelt, 1999a, ADAC-Motorwelt, 1999b, ADAC-Motorwelt, 2000, Haschek, 1999) and expert circles (Day, 1999, Tan, 1997, Brux, 1999) pertaining to just how the potential risk of driving through a tunnel should be generally assessed and which possible improvements exist for safety in tunnels.

When contemplating the relevant issues, it is imperative that one should not simply consider the

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^☆: This article was presented at the ITA Open Session: Fire and Life Safety, at the 28th ITA General Assembly and World Tunnel Congress, 2–8 May 2002, Sydney, Australia.

¹: Past President of ITA—International Tunnelling Association.

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2002 ITA Open Session: Fire and Life SafetyCurrent safety issues in traffic tunnels☆