riobridge

This is one impressive bridge. It is impressive in its statistics, engineering and visual impression.

In terms of statistics: nearly 3km in length, 57m above the water at the highest point, towers 140m high, over water up to 65m deep, 630 million euros in cost, 6 years in construction, envisioned a 100 years ago.

The engineering is impressive also: it is designed to accommodate the seismic activity of the region, as well as the progressive widening of the gulf (30mm a year) due to tectonic activity. Likewise it is designed to handle a crash by a very large ship. The deck is not directly attached to the towers but allowed to float in the event of an earthquake.

The towers are not planted in rock - there is no accessible rock foundation under the water, it is sediment for hundreds of feet. The towers are simply placed on a gravel bed over stabilized sediment. The towers are hollow with access to the foundations and an elevator to the top.

It's longest span is 560m. There are many bridges with individual spans longer than that, but when overall length supported by cable-stays is considered, the bridge ranks second in the world at 2,252m (this length does not include the support ramps on either side).

It was finished early to allow the Olympic torch to pass before the 2004 Athens games.

Visually it is quite impressive also: a fitting addition to its setting, simple, powerful lines.

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Last modified 3/22/14; posted 6/18/09; original content © 2014, 2009 John P. Nordin