This news article was originally written in Spanish. It has been automatically translated for your convenience. Reasonable efforts have been made to provide an accurate translation, however, no automated translation is perfect nor is it intended to replace a human translator. The original article in Spanish can be viewed at Nitrógeno líquido para el futuro puente de San Francisco

Liquid nitrogen for the future bridge in San Francisco

01/02/2004

Air Liquide has been chosen to provide, in a very short period of time, significant quantities of liquid nitrogen needed to cool the concrete used in the foundations of the new bridge that will connect the city of San Francisco to Oakland Bay, in California. This bridge, 3.5 km, will be operational in 2008. It is designed to better resist the possible earthquakes to the current bridge, which was damaged by the earthquake of 1989.

Nitrogen, the main component of air, is characterized in liquid state by its very low temperatures (- 196 ° C), which gives numerous industrial applications. It is used, among other things, to freeze unstable or very wet soils at the time of the laying of foundations. In the case of the Oakland Bay Bridge, has allowed, thanks to its extraordinary cooling power, standardize the temperature of the concrete to less than 10 ° C, by injecting nitrogen in each truck just prior to the casting.

The Californian team of Air Liquide America knew how to respond to this exceptional request and provide more than 227,000 liters of liquid nitrogen for 40 hours in continuous to cool some 10,000 tons of concrete, ensuring delivery of unique injection to the head of work, and a continuum of necessary temperature control.