Marine: $500,000 to $2 Million
ARC Terminal Dock Refurbishment,
P&H Construction Corporation
The ARC Terminal Dock Refurbishment Project consisted of the
restoration of the existing dock that was built in the early 1940s.
In this project, P&H Construction Corporation had to install a
combi-wall adjacent to the failing dock, which began using an APE
100 vibratory hammer. Due to varying soil conditions, P&H suggested
setting the pipe and sheet pile with the vibratory hammer in
the upper loose soil layers and driving to grade in the tighter soils.
This method also alleviated issues regarding movement of the dock.
One of the major challenges on this complicated project was determining
how to place the backfill under the dock in order to ensure
it was 100 percent bearing on underwater sand fill. In all, it took
two weeks and more than 10,000 cubic yards of underwater sand
fill. P&H used a jetting process for the 1,000 linear feet of the dock;
after completion of the sand fill, P&H placed more than 48,000
cubic yards of underwater backfill and stabilized the dock with no
undue settlement. Another challenge was managing the constant
barge and ship loading and unloading operations at the terminal.
Since the new combi-wall was being installed outside of the new
dock, there was nowhere for the ship to berth. ARC Terminal
would have to determine the length of the ships so temporary
moorings and breasting structures could be installed in the correct
locations without impacting the day-to-day operations.
Read about the ARC Terminal Dock Refurbishment by P&H
Construction Corporation on page 106.
Marine: Greater than $5 Million
South Carolina Ports Authority – Wando Terminal
Improvements, Cape Romain Contractors, Inc.
This project included phased repairs and improvements to a 3,800
linear foot reinforced concrete container wharf; driven pile, both
old and new, play a crucial role in supporting critical infrastructure
at the South Carolina Port Authority in Charleston, S.C. Cape
Romain used many pile types, hammer types and different pile
driving techniques. The project required the successful design and
use of a Temporary Noise Attenuation Pile (TNAP). This was
required in order to meet strict environmental guidelines regarding
pile installation by USACE and U.S. Fish & Wildlife. The
noise attenuation requirements were a first for the Charleston area.
Strong environmental concerns were placed on the pile driving
to protect the breeding of short-nosed sturgeon. Mitigation and
solutions to these concerns and requirements were to design and
construct the project using the TNAP system, based on a similar
system tested and observed by the Washington State Department
of Transportation in 2007. Utilizing the half-inch steel plate shells,
closed-cell foam insulation panels and increased plywood cushion
thickness, it was conservatively estimated that the driving experienced
a 35dB reduction.
The project schedule was also extremely challenging. There
were four phases to the project and a total contract duration of 840
calendar days. Liquidated damages were set at $25,000/day, and
those applied to phasing milestone dates, as well as the overall contract
end date. Unique to this project was an in-situ dynamic testing
program, wherein 35-year-old 18-inch PSC piles and 25-year-old
24-inch piles were tested, in an attempt to measure in-place and
current capacities, versus capacities measured when the piles were
originally installed back in the 1980s and ‘90s.
The resistance increase, by percentage, ranged from 41 to
119 percent. In certain cases, the initial pile bearing resistance was
calculated at approximately 300kips, and that was raised to over
600kips, with the revised allowable pile bearing resistance. As a
result, estimated construction costs savings was 15 percent of the
construction budget, approximately $9 million dollars. The overall
quantities of piles required were reduced by as much as 35 percent.
Read about the South Carolina Ports Authority – Wando
Terminal Improvements by Cape Romain Contractors on
page 112. t
PDCA PROJECT OF THE YEAR AWARDS
One of the major challenges on this
complicated project was determining
how to place the backfill under the dock
in order to ensure it was 100 percent
bearing on underwater sand fill.
86 | ISSUE 4 2017