at distances of four to 25 feet from the existing buildings. The piles
were driven with a Junttan HHK4 hydraulic impact hammer, which
has a ram weight of 8,820 pounds and a variable drop height ranging
from 1.0 foot to 4.0 feet. GZA monitored ground surface vibrations
and noise levels with four seismographs and four dosimeters.
All instruments were synchronized with the PDA to allow comparison
of vibration and noise levels with pile depth and drop height.
A comparison of surface vibrations inside and outside of the
buildings showed a significant loss of energy as the wave entered
the building. The loss of energy was due to wave reflection at the
interface of the foundation. Inside the building, surface vibrations
varied from 0.047 ips to 0.122 ips. Outside the building, surface
vibrations varied from 0.127 ips to 0.471 ips. Comparisons of simultaneous
readings showed a reduction factor of approximately three
The Maritime Center personnel were pleased with their
observed behavior of the animals during and after the pile driving.
In conclusion, the pile test program demonstrated that
HP10x42 piles could be safely installed to support service loads
up to 121 kips while not exceeding stringent vibration criteria and
not disturbing the nearby marine wildlife. The critical aspects of
the pile driving regarding controlling vibration and noise included
the use a hydraulic hammer with easily adjustable drop heights for
the ram.
Vibration
One aspect of the pile driving industry that is often overlooked is
the sensitivity of adjacent structures to vibration-producing construction
ENGINEERING AFFILIATE MEMBER
Geotechnical/structural instrumentation is critical on pile
driving projects to monitor ground-based vibrations, resulting
ground conditions and potential adjacent structure deformation.
Recent advances in technology now allow the project team
to automate instrumentation components to allow for real-time
remote data collection, processing, visualization and analysis – all
of this is available on a secure, customizable web-based monitoring
platform. These systems can be designed to notify the project
PILE TESTING EQUIPMENT
SPX POWER TEAM
RENTALS • SALES • SERVICE
operations.
to six.
• Hydraulic Jacks 0-2000 Tons
• Loadcells with Digital Readout Boxes - 0-2000 Tons
• Centerhole Jacks 0-1500 Tons
• Dial Indicators 0-14 inches
• Power Units - Electric, Gas or Manual
• Calibration Services up to 2000 Tons Traceable back to NIST
Loadcell
Digitial Readout Box
Test Pile
Hydraulic
Jack
Dial Gauges
W.B. Equipment Service Company, Inc.
Supplier of Hydraulic and Pneumatic Jacking Systems for Jacking and Pile Testing.
Toll free: 866-522-5464 • Fax: 201-438-7830 • Email: stephen.cireco@verizon.net • Web: www.wbequipment.com
Photo: New York State Thruway Authority
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