Thursday, August 20, 2009

Safety revamp after Balfour/Carillion bridge fall

Rail experts are recommending a shake-up in safety on civil engineering sites following today's publication of a report into an accident at London's Liverpool Street station when a train hit debris which had fallen from a bridge under construction.

The Rail Accident Investigation Board probe centred on an incident in May 2008 when a train collided with concrete planks lying on the track.

The concrete had fallen from a bridge built by a Balfour Beatty/Carillion joint venture following the failure of supports at one end of the bridge deck.

This failure caused a sudden jolt which shook the deck, dislodging the concrete planks.  Damage to the train was minor and there were no injuries.


Safety revamp after Balfour/Carillion bridge fall


Concern over the stability of the bridge resulted in the signaller stopping all other trains in the vicinity. It was some hours before the safety of the structure could be assured, and services did not recommence until the following day.

Investigators found that the concrete fell because of :

• the unexpected movement of the bridge deck which was positioned on a steep gradient and inadequately restrained;

• an inadequately planned operation to restore the deck to its correct position.  This involved modification to the temporary supports and caused them to become unstable; and

• the decision to omit a recommended connection between individual pre-cast concrete planks, which allowed the planks to fall from the deck when it was exposed to a large jolt, and fall onto the track;

The report said a contributory factor was "Balfour Beatty/Carillion's decision to delegate responsibility for temporary works checks to Fairfield Mabey, which meant they lost visibility of how the structure was performing, or of measures being taken to correct the horizontal movement." Since the incident, the bridge has been repaired and completed.

As a consequence of this accident, the RAIB has made seven recommendations, targeted at Network Rail, Health and Safety Executive, London Underground Limited, Rail for London, the Heritage Rail Association, the Light Rail Engineering Group, Northern Ireland Railways and National Express East Anglia, the operator of the train. These recommendations cover the following areas:

• Safety Management Systems and procedures, to satisfactorily approve construction work on or over operational railways.

• procedures so that information is available to operations staff where construction activities might affect the safety of the railway.

• the expansion of the Network Rail’s National Emergency Plan in the light of this incident.

• the wider promulgation of issues identified from this incident amongst the civil engineering community.

• the enhancement of incident management training given to operations staff.

Murfreesboro’s Broad St. bridge repair is completeBuild Center worker killed by sheet of glass