Representative Anthony Weiner: Test Bridge Stress,Vibrations
Representative Anthony Weiner released the following statement on Wednesday in response to news reports that New York State Energy Research and Development Authority (NYSERDA) and New York State Department of Transportation (NYSDOT) has begun a test program of new wireless sensors to test bridge stress and vibrations that could eventually be used on the state's 17,000 bridges. This past August, Weiner was joined by local lawmakers in calling for the installation of new fiber optic stress detection technology on bridges to allow for year around inspection that could prevent a catastrophic bridge failure like the tragic incident in Minneapolis. Currently, bridges are inspected every two years, approximately 90% of which are conducted visually.
"While our bridges are safe, we have to be vigilant and proactive in keeping them that way.
"This low cost and effective technology will allow us to predict problems and have virtual inspectors on our bridges 24-7, it's simply a nobrainer."
Due to recent technology advances, fiber optic sensors can be installed on spans and enable bridges to signal for help the moment structural problems arise. A series of sensors embedded in the bridge communicate wirelessly to a computer and provide engineers with a real time picture of a bridge's health and safety so that problems can be acted upon immediately.
The sensors detect minute strains and changes in a bridge, leading to the immediate identification of cracks or weakening in the structure. In addition to identifying cracks, the sensors can detect the speed at which those cracks are spreading, identify the stress caused by heavy load and natural elements such as heat and wind, and also measure corrosive activity. The sensors don't require batteries and would remain operational for many years.
The cost of implementing this preventive technology is modest. For example, the installation of a fiber optic system on a 1000 foot span similar to the collapsed bridge in Minneapolis would have cost approximately $185,000. In contrast, the federal government has already directed $250 million for the rebuilding of that bridge, with the final cost estimated up to $350 million. The cost of installing sensors on a larger span such as the Brooklyn Bridge is an estimated $250,000 to $500,000.
Fiber optic sensor programs have already been successfully used around the world - including the Manhattan and Third Avenue bridges in New York City. Sensor technology is being used in California, Colorado, Georgia, New Mexico, Ohio, Pennsylvania, Wisconsin and countries such as Canada, France, Germany and Japan. After using the technology on three bridges in New Mexico, their state Department of Transportation is interested in adding the mechanisms to all new bridges as they're built. In Wisconsin, Governor Jim Doyle recently ordered that sensors be added to 15 bridges with similar design to the bridge in Minneapolis.
According to a 2006 report by the City, 84% of New York City's 19 largest bridge spans are in poor or fair condition. Despite spending $3 billion on bridge reconstruction over the last 8 years, the federal Department of Transportation has deemed 178 of the city's bridges as structurally deficient, which signifies they're in need of work but not in danger of imminent collapse.
While our city's bridges are safe, decay from rust on steel gussets used in nearly all of the city's steel bridges could eventually critically weaken supporting structures, and the cost to repair all the spans is prohibitive. As New York City and the nation face infrastructure maintenance costs that dwarf the amount of funds currently budgeted, sensor technology will provide invaluable information as to which bridges need repair first.