Ha'penny Bridge, Ireland
The Ha'penny Bridge, built in 1816, is regarded as one of
Dublin's engineering and architectural gems. It is one of the
finest early examples of the use of cast iron in bridge
construction. The bridge is a 3m wide pedestrian, 43m span,
elliptical arch over the River Liffey in the city centre. The
principal structural elements are three parallel vierendeel arched
ribs of cast iron made into six sections.
To refurbish this Grade I listed structure Mott MacDonald carried
out a condition survey, followed by the design and supervision of
remedial and strengthening works. The conservation works comprised
the repair of the cast iron arches which are the main supports to
the deck and superstructure; the repair and some renewal of the
railings; the vertical realignment of the deck to its original
profile; and lighting and redecoration of the structure.
Conservation principles required that as much of the original
fabric of the bridge be retained, and in fact 98% of the original
cast iron was re-used. The success of the restoration is due to the
fruitful marriage of the best international standards in
engineering excellence, architecture conservation practice,
sensitivity in execution and meticulous attention to detail.
This beautiful bridge has been preserved for its original purpose
and will continue to service future generations, as it has done so
graciously for the last 187 years. It maintains its place as a
highly valued component of the cultural heritage of this city, the
nation and Europe. Our work on this bridge won a Europa Nostra
award in 2002 in the ‘architectural heritage’ category.
