The Technology – Reinhall Piles™

A breakthrough in noise mitigation

Noise from impact pile driving is transmitted both through the water and the seabed. To be effective, a noise attenuation method must therefore restrain noise along the full length of a pile as it is being driven to its target depth. Attenuation cannot stop at the seafloor.

We have developed a patented solution that uses a conventional steel pile’s outer wall to encapsulate noise along its full length. We insert a fixed or reusable inner pipe for driving purposes, in essence creating a double-walled pile. The driving hammer strikes the inner pipe. Sound waves then travel along the inner pipe while the outer pipe mitigates noise transmission. After installation, the inner pipe is either left in place or removed and used as a reusable mandrel.

Method Comparisons

The proof – WSDOT/FHWA test data

TESTED UNDER RIGOROUS EXPERIMENTAL CONDITIONS

The University of Washington (UW) Department of Mechanical Engineering conducted a full-scale test of our pile technology in Puget Sound October 2014. The test was designed and conducted using rigid experimental controls. It was sponsored by the Washington State Department of Transportation (WSDOT) and Federal Highway Administration (FHWA). Site characteristics were typical of those where ferry terminals and other nearshore marine structures are constructed.

During the test, three piles were driven: (1) A 30” diameter standard steel pile, which was our experimental control; (2) a 30” diameter double-walled Reinhall Pile™ and (3) a 30” diameter mandrel-driven Reinhall Pile™. All piles were driven with industry standard techniques and standard equipment. The UW Applied Physics Laboratory (APL) harvested and analyzed the acoustics data.

Reinhall Piles™ achieved 21-23 dB PEAK noise reduction vs. the standard pile. This compared to a 3-6 dB PEAK noise reduction for the bubble curtain. A separate hydrophone deployed by WSDOT registered a 23-27 dB Peak reduction for Reinhall Piles™. These results were consistent with previous experimental results and confirm the breakthrough in noise mitigation now available for marine construction projects. 

  Double Walled Pile Mandrel-Driven Pile
PEAK Reduction – 21.2 dB – 23.2 dB
SEL Reduction – 17.2 dB – 18.0 dB
RMS Reduction – 19.1 dB – 20.7 dB

Learn more about Reinhall Piles™

Time Lapse video from WSDOT-sponsored full-scale test

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.

Reinhall PileTM technology is protected under the following issued or pending global patents:

11735115.5, 2,784,811, US8,622,658 , 2,854,007, US9,068,317, US9,080,301, 12846393.2, 14/148,720, and 14/864,762

 

"By reducing underwater noise from pile driving by 20 dB, implementation of MCT’s technology could potentially reduce the Zone of Influence and required marine mammal monitoring, expedite consultation processes with the Services, and minimize construction delays due to the proximity of marine mammals."
Cameron Fisher, Biological Lead, 48 North Solutions, Inc.

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.