IRSE News 140 Dec 08.pdf

PORTSMOUTH
IRSE
The Manchester South and Portsmouth
Resignalling Projects – a Retrospective View
by Clive Kessell
Part 2: Portsmouth Area Resignalling Scheme
Way back in April 2007, a letter was published in the NEWS pointing out that we had not published anything about the huge
problems encountered on two schemes, Manchester South and Portsmouth. This fact was reinforced by several respondents to
the IRSE 2007 Survey.
This comprehensive article hopefully overcomes this omission, and gives a full account of the problems and solutions.
B
y contrast to Manchester, resignalling the
Portsmouth area should have been straightforward.
Driven by the need to renew and remodel the Permanent
Way plus the deterioration of the 1960s signalling equipment, this
was a classic type scheme. Portsmouth was one of four Southern
area signalling projects, the others being Basingstoke,
Barnham – Bognor and East Kent. Tendered as competitive
contracts, all four were eventually let to preferred bidders on a
negotiated target cost basis. Siemens, with a proven system in
work at Bournemouth, got Portsmouth, which was seen to have a
similar engineering and operational environment.
The Portsmouth scheme was based around a new signalling
centre at Havant, with boundaries to Chichester, Petersfield and
Fareham (Eastleigh power box), plus the control of all major
junctions within this area. Around 80% of the UK interlocking rules
had been used at Bournemouth (including swinging overlaps)
within the SIMIS-W interlocking, either directly in the Bournemouth
application or in the testing facility used to support the safety case.
Portsmouth would need to take this to 90%. New applications
were level crossings, Patrolman’s lock out, banner signals on
subsidiary signals and other specific logic agreed between
Siemens and Network Rail engineers. Axle counters would replace
track circuits but these were the same as Bournemouth. So why
did it all go wrong and what were the causes?
Scheme Design and the Contract Plan
The scheme design was assigned to Parsons Brinkerhoff and this
was used as the basis for determining the main contract scope
and price. From this a number of sub-contracts emerged. The
overall contractual structure was:
Signalling Scheme and Detailed Track Design
Parsons Brinkerhoff ;
Trackwork and Traction Supply Balfour Beatty;
Signalling System Design and Supply Siemens;
Telecommunications Scheme Design Network Rail;
Telecomms Detailed Design and Supply Siemens;
Miscellaneous Telecom Works Thales;
Power Supplies
Siemens;
Control Centre Civil Work
Osbornes;
Fringe Train Describers Siemens (sub- contract to GETS).
Mention must also be made of the Safety Assessor work done by
Lloyds Register for the Siemens works.
Network Rail provided a conventional project team led by a
Senior Project Manager and a Designated Project Engineer. The
contract was awarded in late March 2005, some 8 months later
than originally planned. To make up for this loss in time, the
commissioning, which had been planned for two stages, was
condensed to a single stage, with 9 preceding Permanent Way sub
stages. A general line speed increase was planned with the
remodelled layouts and new signal spacings took account of this.
Scheme plan changes caused by a change in the track layout
IRSE
NEWS Issue 140 December 2008 19