Wind Tunnel Testing

CP&A pioneered the use of modern wind tunnel technology for container crane design and we remain the world leader in that specialty. 

Older technology used wind tunnels that were primarily intended for subsonic airplane design.  Airflow in these tunnels is a constant speed with minimal turbulence.  That was realistic for airplanes but not representative for wind loads on civil engineering structures such as buildings, bridges, and cranes.  Nowadays a Boundary Layer Wind Tunnel is used for such structures.  Turbulence and other ground effects are deliberately modeled to be representative of actual site conditions.  Thus, time varying effects such as gust, height, size, and 3‑dimensional shielding are combined for a particular structure and site condition.  They are measured and reported to us as global turntable reactions. 

For design, we use the wind tunnel measurements to produce equivalent static member loads which produce global base reactions equal to the turntable reactions.

The model for one test had numerous pitot tubes to measure pressures to individual members.  This data was used to fine tune the equivalent static member loads used in our proprietary container crane design software.

For both design and design review, CP&A have the experience and expertise.