The voice of concrete products - British Precast

BRITISH PRECAST BEST PRACTICE AWARDS 2008
Innovation
Award
Milton Precast – quick moveable barriers:
Concrete – keeping us on the move
“The decision
was taken to
install a moveable
concrete barrier
system that would
enable an
extremely rapid
method of traffic
separation or
contra-flow
operation when
required.”
Figure 1: Quick
moveable concrete
barrier units.
As a long-time supporter of a safer,
faster road network, Milton jumped at
the chance to be involved in
manufacturing a quick moveable
highway barrier (QMB) system that
would make use of its concrete
production experience and technology
built up over half a century.
John West, Milton Precast
Congestion on the southbound M20, due to a number of
French transport, wage and fishing disputes, has long
been a regular occurrence. The Department of Transport
had looked at several methods to remedy a time-consuming
and hugely costly problem affecting all users of the
motorway. Traffic jams were often backing up some 30
miles to Junction 4, Snodland, and local towns became
gridlocked as motorists attempting to find a way around
the problem left the motorway and became entangled in
the mêlée.
The decision was taken to install a moveable concrete
barrier system that would enable an extremely rapid
method of traffic separation or contraflow operation when
required. The QMB system is an American innovation and
uses a specially built vehicle to lift and position the units
very quickly and safely. The vehicle can move and position
units at up to 10mph. Each unit, which is 1m long, 1m high
and 600mm wide, weighs 680kg. The versatility and flexibility
of the system, along with the barrier's longevity via
its use of concrete, make the system an extremely competitive
and safety-conscious option.
The work to provide space for the barrier along the central
reservation and to change the layout of Junctions 11a
and 12 began in May 2008. To limit disruption, work was
carried out 24 hours per day, 7 days per week. ‘Operation
Stack’ was born.
Once the work was completed it would reduce pressure
on the A20 diversion route, improve safety, smooth traffic
flow and shorten journey times very considerably. The end
result would be happier motorists and less stress for all
concerned.
Milton has a close relationship with US firm Barrier
Systems Inc, but as the company operates from California,
telephone calls etc have to be timed correctly so that they
do not get them out of their beds too early! Highway Care
supported Milton for the whole process, being the UK
point of contact. Due to the nature of the work, and to minimise
noise and disruption, Milton operated a night shift
when the barriers were collected. Good communication
between Highway Care and Milton ensured that this inconvenience
for the local community was kept to an absolute
minimum.
The majority of the components were shipped from the
US in containers. Milton had to supply some reinforcing
but primarily just the concrete. This ‘shipping part’ was the
most troublesome part of the project due to the fact that
Milton Precast has a low bridge on the road to its production
site. Some would go under the bridge, others had to be
offloaded at the main site and loaded on to their own trailer
for transporting – a time- and labour-consuming task.
Safety on-site was the main priority during the whole
process. Strict ‘truck arrival’ timing had to be observed
between Milton and its ready-mixed concrete supplier,
(Photos: Milton Precast.)
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Reproduced f ro m CONCRETE December 2008/January 2009 © The Concrete So c i e t y, 2008