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Notes to editors

…like painting the Forth Bridge (British)

If repairing or improving something is like painting the Forth Bridge, it takes such a long time that by the time you have finished doing it, you have to start again. ‘Home improvements are a bit like painting the Forth Bridge. By the time you've finished the kitchen, the bathroom needs decorating and so it goes on.’

Cambridge International Dictionary of Idioms © Cambridge University Press 1998

Forth Bridge facts

Age of Bridge: Opened 1890 (121 years old)

Length of Bridge

Overall: 2,467 metres

Main structure (portal to portal): 1,630 metres

Height of Bridge

High water to top: 110 metres

Foundation to top: 137 metres

Materials

Weight of steel in bridge: 53,000 tonnes

Number of rivets: 6.5 million

Concrete and masonry in piers: 120,000 cubic yards faced with 2ft thick granite

Operational information Number of trains per day: 200 Number of passengers per year: 3 million

Painting the bridge

Painting area: 230,000 sq metres

Volume of paint used: 240,000 litres

Lighting the bridge:

Total number of lights installed: 1040 lights

Length of cabling required: 35,000 – 40,000 metres

History:

1873 Thomas Bouch’s first design for a suspension bridge across the Forth presented

1879 Bouch’s design for the Forth Bridge abandoned following Tay Bridge disaster

1882 Design submitted by John Fowler and Benjamin Baker approved

1883 Construction of Fowler and Baker’s cantilever structure began

1885 Last caisson launched

1886 Pier foundations completed

1887 Three towers completed

1889 Cantilevers completed

1890 Bridge formally opened by Prince of Wales on 4 March 1890

• 57 lives were lost during the construction of the Forth Bridge
• At the height of its construction, more than 4,000 men were employed

The construction of the bridge resulted in an unbroken East Coast railway route from London to Aberdeen.

Contractors:

The main contractor is Balfour Beatty Regional Civil Engineering based in Edinburgh and is undertaking the restoration works with four principal sub-contractors – Pyeroy Ltd, specialists in blasting and coating ; Harsco Infrastructure, specialists in access systems and encapsulation; RBG Ltd, specialists in steel repairs, and ThyssenKrupp Palmers Ltd who facilitate for all three activities.

General:

Up to 320 people working on the bridge at peak times – many of whom are locally based.

Scope of the Works:

• The painting process involves the erection of significant scaffold access systems to access the working areas and screening the area to be painted to prevent debris affecting or contaminating the surrounding environment.

• Old paint is removed using an abrasive blasting preparation and the steel coated with an industrial protective coating system.

• The paint used to coat the bridge is a specialist glass flake epoxy paint, similar to that used in the offshore oil industry and designed to last 25 years. It is, however, expected to last much longer.

• WJ.Leigh of Bolton is the supplier of the specialist paint and coating systems

• Repairs and replacement of walkways including the installation of new walkways and catwalks to allow for access to the works and to assist in the future examination and maintenance of the bridge.

• Steel repairs - replacing small localised sections of steel where required

• Refurbishment and maintenance of the architectural lighting system

Painting Method:

·

Essentially each section to be painted is surrounded by a scaffolding system and then encased in a “film like” encapsulation material.

The purpose of this is to capture all the debris from the removal of the old paint and from any steel repair work. This also provides a protected environment within which coatings can be applied and allowed to cure.

The project team is very conscious of its environmental responsibilities and have imposed stringent control measures to ensure that the surrounding environment – and the Firth of Forth – is protected from any contamination.

After thorough cleaning of the steel structure paint is applied both by airless spray and by hand in areas of particularly difficult access, each of the 6.5 million rivet heads are painted by hand.

The principal priority is safety of all the workforce and contractors working on the project and all the appropriate and specialist personal protective and specialist safety equipment is supplied and used for each and every activity, including regular health monitoring.

Work has progressed dependant on two key issues: the urgency of the repairs and balancing the scaffolding loads efficiently.

Currently the bridge supports approximately 4,000 tonnes of scaffolding access systems.

Area of steel requiring paint: 250,000m2