Bridges can be vulnerable to extreme wind conditions, therefore the constant monitoring of bridges is vital for both structural integrity and the safety of bridge users. In some cases, due to the distance above the ground and the height and design of the structure, 3 dimensional wind measurements are required to better understand wind loading as well as strain from gusting conditions.

To provide this crucial measurement data, Gill 2-axis and 3-axis ultrasonic anemometers have been installed in bridge applications around the world for over 20 years.

In applications where basic wind measurements are required such as transport safety, Gill’s WindSonic and WindObserver sensors are commonly used to alert bridge management to restrict high-sided or vulnerable vehicles crossing, or in severe conditions, to completely close access to the bridge. Gill WindSonic and WindObserver ultrasonic anemometers are often selected because they provide instantaneous measurement responses to changing wind conditions. Installations of this nature can be seen in bridges across the world. Some located in the USA are:

• Florida State Transport Authority
• Niantic River Amtrak Train Bridge (Connecticut)
• Fore River Bridge (Massachusetts)
• Tobin Bridge (Boston)

3 dimensional wind measurements are crucial for complex terrain and where local meteorological effects from specific wind vectors could impact structural safety. Gill 3-axis ultrasonic anemometers, such as the WindMaster and Research ranges, provide extremely precise, fine scale, fast (10-50 Hz) vectorial 3 dimensional measurements. When utilised together with strain gauges, the data helps determine high Reynolds numbers and stress values, which are useful for onsite safety condition monitoring.

Gill 3-axis ultrasonic anemometers provide data on some of the Worlds’ iconic bridges including:

• The Millennium Bridge , London
• The Severn Bridge motorway crossing, Wales
• The Tsing Ma Bridge, Hong Kong
• The Clifton Suspension Bridge, Bristol
• Millau Viaduct in Creissels, France

For more information on the use of Gill anemometers for bridge applications visit the application page here, or contact 01590 613500.