3 min reading time
Story 108 – 2009 – Quality

An old principle brilliantly reinterpreted

Tin bronze from Wieland adorns an obelisk in Madrid

When a modern obelisk was erected in Madrid in 2009, those responsible put their trust in Wieland's know-how and quality: numerous movable slats made of tin bronze give the monument an unparalleled appearance.

Obelisks belong to the oldest cultural assets of mankind. World-famous are those ancient stone pillars, which stand for example on St. Peter's Square in Rome or on the Place de la Concorde in Paris. However, one of the most visually striking and constructively sophisticated obelisks dates from 2009 and is located in the Spanish capital Madrid: the "Obelisco Calatrava".

The occasion for its construction was the 300th anniversary of the Caja Madrid savings bank, which commissioned the Venetian star architect Santiago Calatrava with the design. On the Placa de Castilla, the obelisk was intended to provide a special contrast to the two spectacularly inclined "Torres Kio" office towers – and at the same time form their visual centre. Calatrava designed a structure of superlatives for this purpose: the 93-metre high supporting framework was erected from 400 tonnes of steel, to which 7.7-metre long movable bronze slats were attached which are set in motion by 100 hydraulic drives. This principle creates the illusion of a perpetual wave – especially since the gold-plated outer surfaces shine particularly brightly in sunlight and form a spectacular, dynamic contrast to the bronze-coloured side flanks of the slats. This effect is further enhanced by spirally mounted, two-coloured granite plinth platforms.

In the summer of 2008, the customer Cuñado and the general contractor Acciona were convinced of Wieland's capabilities for this project – partly during negotiations in a construction container standing exactly at the current location of the obelisk. Wieland's participation in the determination of the material characteristics played an important role in this.

And so Wieland supplied 100 tonnes of tin bronze strip Wieland-B16 to Spain, each 5 millimetres thick, in widths of 135 and 400 millimetres and in lengths of 3.7 and 4 metres. They were formed and welded to form the 7.7 metre long hollow sections which appear as lamellas when viewed from the outside.

No less a person than King Juan Carlos I inaugurated the work of art in December 2009, which was then solemnly presented to the City of Madrid as an anniversary gift. There, in a city that is not poor in sights, it is now one of the most attractive "eye catchers".

100 tons of tin bronze strips from Wieland formed the starting material for the obelisk’s slats. They were later formed into hollow sections and partly coated with gold.