Usually, a bridge is supposed to carry you over
the waves, not turn into a wave itself.
Russian President Dmitry Medvedev has just ordered
officials in Volgograd Oblast to once again thoroughly check the safety of a bridge across the Volga River after it began undulating and swaying in the wind last month. He's also asking them to look into the construction and financing of the span.
The bridge closed on May 20 after cars were thrown a meter into the air and spun around 180 degrees due to a phenomenon called mechanical resonance or harmonic oscillation, which is when the frequency of an object's oscillations matches its natural frequency of vibration. Or something like that. My favorite TV show, "Mythbusters,"
tested the idea that soldiers marching in unison can cause a bridge to collapse due to harmonic oscillation. They deeemed it "plausible."
An initial probe by the Russian Prosecutor-General's Office and the presidential administration found "inadequacies" in the work of local and federal officials in the design, construction, and use of the bridge.
, taken back in April, also seems to show the bridge jumping under a car in an alarming way.)
Construction of the bridge began in 1996 and cost 2.5 billion rubles ($80 million). It opened in October 2009, with Deputy Prime Minster Sergei Ivanov cutting the ribbon.
The bridge was stress-tested on May 22 and passed. It reopened to "light vehicles," such as cars, on May 25, but only when the wind is less than 16 meters per second.
The whole thing reminds me of the famous clip of the Tacoma Narrows Bridge,
known as "Gallopin' Gertie," swaying in a storm in 1940. That bridge eventually collapsed, four months after its grand opening.
Here's hoping history doesn't repeat itself.
-- Grant Podelco