THE North East is leading a project to make train carriages better able to withstand terrorist bomb attacks.
Headed by Conor O’Neill in the NewRail research centre at Newcastle University, the three-year operation has focussed on containing the impact of a blast and reducing flying debris, which is the main cause of death and injury in an explosion and the key obstacle for emergency services trying to reach passengers.
Analysing the carriages involved in the London Underground bombings, the team of experts from four EU countries has re-designed current vehicles and has just completed full-scale tests on a prototype.
Mr O’Neill, based in the School of Mechanical and Systems Engineering at Newcastle University, said: “The Madrid bombings in 2004 and the 7/7 attack in London the year after highlighted how vulnerable trains are to attack – particularly busy metro and commuter trains.
“At the same time we have to be realistic – completely replacing existing vehicles isn’t an option. Instead, we have developed and incorporated new technology and materials into existing carriages to improve performance.
“What we’ve shown is that companies could make relatively cost-effective and simple modifications that would significantly improve the outcome of an attack.
“This is a unique project not least for the sheer scale of the testing we have done.
“We have concentrated on metro vehicles because large volumes of people use them, but the technologies also apply to local passenger and high speed national trains.”
In a controlled, full-scale explosion on a decommissioned metro carriage, the team measured the impact that a terrorist attack can have.
Understanding the progression of the blast wave as it travels the length of the coach was key to understanding how the interior furnishings reacted.
Filming the explosion – which takes less than a second – the team used high-speed cameras to slow down the blast footage in order to understand the mechanics of the explosion.
Learning lessons from this experiment, a similar test was carried out on a prototype, designed and built specifically with blast resilience in mind.
Tethering down heavy equipment such as ceiling panels using retention wire, plastic coatings on windows and the replacement of heavier structures with lighter-weight and energy-absorbing materials were some of the key modifications made.
“Preventing flying objects is the key,” said Mr O’Neill. “Tethering ceiling panels reduced the risk of fatalities and injury from flying shrapnel and also meant the gangways were kept relatively clear of debris, allowing emergency staff quick access to the injured.
“The window coating we developed was also incredibly effective. Without it the windows are blown outwards – putting anyone outside, such as those standing on a platform, at risk from flying glass.
“With the plastic coating you see a clear rippling effect as the blast moves through the train, but every window remains intact apart from the safety windows which are designed to be easily knocked out.”
The researchers also investigated the benefits of dividing up the carriages using energy-absorbing materials that reduce the impact of the blast.
The team is now in a position to advise the rail industry and EU Commission on which approach will improve the resilience of rail vehicles to blasts.
Mr O’Neill said: “A bomb on a train is always going to be devastating, but what we are trying to do is find a way in which the vehicle itself can help to mitigate the impact of an attack. These are all low-cost, simple solutions that can be put on existing trains which could not only save lives but also reduce the attractiveness of railways for potential terrorist attacks.
“How this will be implemented will now be assessed by the industry and the EU Commission.”
Companies could make cost-effective and simple modifications that would improve the outcome