It has become a tradition for the Construction Materials Group to arrange a general interest building or transportation evening meeting each December, as far as possible with a London emphasis, to which members, partners and other Society guests are cordially invited.
The event, on 10 December 2009, was entitled 'London and Budapest: Their bridges and rivers' and was given by Sandor Vaci, RIBA. Mr Vaci was born in Hungary and studied in England and the USA before practising as an architect in London.
Cities are almost always sited by the coast or on a river, the Danube is an international waterway and the Thames estuary has formed a seaport since ancient times. The Romans were excellent engineers and were responsible for the first bridges across both rivers, but with the decline of the Roman Empire only ferries were available until mediaeval times. The 21 arches of London Bridge (built in 1206) created a major problem for navigation due to the speed of the water. But in Budapest the problem of winter ice formation at that time only permitted a seasonal ‘boat-bridge’ to be constructed.
As construction techniques improved it was possible to build bridges with wider spans and Old Westminster Bridge (1750) had 15 arches and Old Waterloo Bridge by John Rennie (1817) had just 9 arches.
The next major advance in technology was the development of suspension bridges. These enabled much greater spans to be achieved thereby minimising interference with river traffic. Hammersmith Bridge (1828) was the first Thames bridge of this type soon followed by Marlow Bridge, both by William Tierney Clark.
Tierney Clark was also responsible for the design of the first suspension bridge in Budapest. Commemorative plaques have recently been placed by the Danube and by the Thames at Marlow to mark this association.
Later bridges have adopted alternative principles. In Budapest a cantilever bridge (as used for the Forth rail crossing) was constructed in 1896 to provide maximum clearance for vessels. Over the Thames the twin-bascule Tower Bridge enabled tall-masted sailing ships to navigate to the Pool of London.
World War II
Despite the best efforts of the Luftwaffe all the Thames bridges survived intact in World War II. The Danube bridges in Budapest, however, were destroyed by the retreating Germans to hinder the advance of the Russian army. After the war the Budapest bridges were mostly rebuilt to their original designs, except for the Elizabeth Bridge (1964) that is a single-span suspension bridge (and much better for vehicular traffic).
The most recent Thames crossing is the Millennium footbridge, the low-profile design of which initially developed an uncomfortable sideways sway until restrained by dampers.
Both London and Budapest are threatened by rising water levels and have required considerable flood defences to be constructed. Both cities have also made strenuous efforts to improve access to the Thames and Danube respectively to provide continuous walkways along the river banks for the enjoyment of citizens and visitors.
On behalf of SCI Members and guests, Group Chairman Prof John Bensted thanked the speaker for his fascinating illustrated presentation and invited all present to gather in the Garden Room for seasonal food and wine.