RWDI specializes in studies of the interaction of wind and large structures and, as a result, some of the world's longest span bridges have been tested in the firm's wind tunnels. Such testing is an integral component of long-span bridge design. RWDI's wind engineering services are tailored to meet the objectives of each individual bridge project.

Meteorological/Site Assessment

Wind conditions at the site including the impact of local topography are assessed to evaluate how they translate into the wind speeds and turbulence levels to be considered in the design.

Topographic Model Study

Local topography can impact the direction of the wind, the wind speeds at deck height, and the turbulence intensities along the deck. The effects are evaluated by testing a topographic model in the wind tunnel. Results are used to set the test wind condition for the bridge model tests and to arrive at accurate loads due to wind buffeting.

Sectional Model Study

Initially, stability testing is undertaken to see if the bridge will remain aerodynamically stable against flutter and vortex excitation over a sufficient range of wind speeds. The wind forces on the final deck section are then measured.

Buffeting Analysis

Analysis is conducted to evaluate the response of the bridge due to wind buffeting and resulting design loads for the completed bridge and the construction stages.

Aeroelastic Model Testing of Construction Stages

Possible construction schemes are assessed to determine if stability problems could occur and to provide the wind loads during construction. Construction loads can be refined and the impact of temporary restraints such as tie-down cables can be investigated.

Aeroelastic Model Testing of the Completed Bridge

Three-dimensional effects, such as topographical features and a non-uniform deck cross-section are investigated to assess their effect on the stability and wind loading of the fully constructed bridge.

Cable Vibration Assessment

The susceptibility to wind-induced oscillations of cable-stays is assessed. Methods of suppressing unacceptable levels of vibration are developed.