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by Jim Johnson
Trenchless pipe ramming tools, known
for their ability to horizontally ram pipe through difficult
soils, aren't just for underground anymore.
 Last
spring, BRS, Inc. of Richfield, NC, was contracted by Rowan
County, NC, to install a water line connecting a new baseball
field, used by a Philadelphia Phillies farm team, to the city
of Kannapolis' water supply. This required the installation
of 3000 ft of 8-in. water main. Most of the job would be on
land, but 320 ft of main needed to span a lake.
To cross the lake, the main needed
to be installed next to a bridge which links the town to the
field. Seven pairs of H-beams were to be installed to support
the main. Traditionally, this would be accomplished by using
a pie driver. The problem was that the pile driver setup required
a crane, which was too heavy to be used on this bridge. Although
a crane could reach from the water's edge, it was deemed too
cumbersome to maneuver.
BRS was familiar with trenchless
pipe ramming tools, having used them to install pipe beneath
roadways. Bradford Berringer, president of BRS, first became
familiar with vertical ramming tool applications from trade
magazine articles, sales literature, and video. Commenting on
the possibility of using the ramming tool for the vertical installations,
he stated, "We had no doubts that it would work."
Berringer contacted Eddie Ward, TT
Technologies' Southeastern sales manager to secure some tool
recommendations for his specific beam installations. "We've
done it in the past! declared Ward. TT Technologies is a manufacturer
of trenchless tools and accessories based in Aurora, Illinois.
Assisting Ward in the equipment selection
was Bill Holyfield from A.E. Finley, a regional distributor
of TT tools and accessories. They decided that a Grundoram Gigant
hammer would be the most appropriate tool to use for driving
the beams. It offered the necessary power, was light enough
to be positioned by a boom truck on the bridge, and wouldnÕt
require any modifications.
Berringer agreed with the selection.
He then ordered a tapered locking ram cone which corresponded
to the tool's diameter, with the intention of devising an adapter
to fit the ramming tool to the H-beams. This adapter needed
to firmly hold the tool nose as well as fasten securely to the
top of the H-beam.
Arrangements were made to BRS to
rent a Gigant tool from A.E. Finley. Ductile iron pipe was ordered
and support equipment was arranged with an installation timeline
tentatively established.
The lake crossing commenced when
a boom truck was positioned in just one lane of the narrow bridge,
allowing regulated traffic to flow by it. The truck was easily
repositioned from one point to the next, allowing the boom to
swing the tool from one beam to another. A special beam holder
extended from the side of the bridge and was used to uniformly
hold the pair of beams in place for proper installation.
A BRS crew member made his way out
onto the arm of the holder to coordinate the alignment of the
ramming tool to the beam. The adapter was positioned on the
beam, with the tool lowered into the saddle by the boom operator.
By design, the assembly was held together by inserting a lock
plate.
Once the tool was started, each beam
installation was completed in approximately two minutes. Specifications
dictated that each beam should be driven at least 10 ft deep,
or to refusal. Crossmembers were then installed on each pair
to cradle the 8-in. ductile iron water main.
 "The
job was let one day, we were awarded the contract the next,
and were on the job two days after that. I've never been involved
in a job that went from bid to work so quickly," said Berringer.
The project was rushed to facilitate the opening of the Piedmont
Phillies' season at the brand new ball park. BRS was given only
30 days to complete the entire job, including the land installations
as well as the river crossing.
"We beat the deadline by 10 days,"
declared Berringer. The work originally was to be completed
before the second game of the season, but is was done before
the first game.
BRS was able to install all 14 H-beams
in just one day by using the pneumatic ramming tool. Berringer
claimed that the rammer configuration was so much lighter and
easier to use, it dramatically reduced tool setup time. He estimated
his time savings at an incredible 90 percent, compared to using
a crane. By factoring in the substantial time savings, Berringer
knew that no other contractor could come close to matching his
winning bid.
And when a struggling pitcher was
removed from the mound that first game and sent to the showers,
at least he had plenty of water.
Jim Johnson is a writer for Lime
Valley Advertising, Inc., Mankato, MN.
Trenchless Technology,
July 1995, Page 47
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