Jan. 31, 2015

AUTHORS

Per G. Reinhall and Peter H. Dahl

ABSTRACT

The underwater noise from impact pile driving is studied using a finite element model for the sound generation and parabolic equation model for propagation. Results are compared with measurements using a vertical line array deployed at a marine construction site in Puget Sound. It is shown that the dominant underwater noise from impact driving is from the Machwave associated with the radial expansion of the pile that propagates down the pile after impact at supersonic speed. The predictions of vertical arrival angle associated with the Mach cone, peak pressure level as function of depth, and dominant features of the pressure timeseries compare well with corresponding field observations.

READ FULL ARTICLE

http://scitation.aip.org/content/asa/journal/jasa/130/3/10.1121/1.3614540

"This new research shows we can minimize underwater pile driving noise to avoid harm to mammals and other protected marine species. The new sound attenuation method may also save project construction time and money."
Rhonda Brooks, Research Director, Washington State Department of Transportation

Hear the difference

Recorded from hydrophone deployed at 10m during subscale testing of 8" steel piles in Seattle, Washington in 2013.

You are hearing 4 strikes of a standard pile followed by 4 strikes of a Reinhall Pile™. Notice the difference.