by Jim Schill
The
cable is attached to the tool for the first burst. From
the left, Larry Gross, TT Technologies; Richard Berry
and Scott Moore, Tri-Star. |
The first thing many people
think of when they see the tournament course in Augusta, Georgia,
is perfection, perfectly trimmed fairways, perfectly manicured
greens The beauty and uncommon perfection of the facility
do not, however, exempt it from common problems like infrastructure
deterioration. So when the course’s 6-inch cast iron
water lines began to fail, they needed a contractor that held
the same high standards as they did.
Tri-Star Contractors, Edgefield, South
Carolina has been in the utility pipeline restoration and
replacement business for almost 20 years. They have built
their reputation on attention to detail and meticulousness.
They were the perfect contractor for the job at Augusta.
Richard Berry, President of Tri-Star
Contractors said, "The job was bid as open cut, but I
knew trenchless was the way to go. This is a beautiful golf
course. Even the most carefully executed open cut would be
noticeable."
The course’s on-site plumber had
not been exposed to pipe bursting. Berry said, "I bid
the job based on pipe bursting. When I told the people at
the course that I planned to replace the pipe without open
cutting they just laughed."
Berry even brought a videotape of a burst
he had recently completed. He said, "It came down to
the point that I gave them a price. I told them that one way
or another I had to replace the water main. If I’m successful
with the burst, they would have no disruption what so ever.
If not, they would be no worse off than they originally anticipated.
What did they have to loose?"
After some questioning, Berry received
the go ahead for the project. He turned to TT Technologies
Product Specialists Eddie Ward and Larry Gross for their advice.
The Course
Buildings throughout the facility had
been experiencing problems with water pressure for quite some
time. The 6-inch cast iron water line that carried potable
water to the Pro Shop and other buildings on the course was
no longer functioning properly. Berry said, "The pipe
was old. Most of the line ran underneath the course’s
driving range. Sections of it were terribly tuberculated and
other sections had just plain deteriorated."
Upon walking the course, TT’s Eddie
Ward and Larry Gross identified potential problems with a
pipe burst, the biggest being the joint type. To everyone’s
knowledge, these types of mechanical cast iron joints had
never been pipe burst before. Berry said, "Eddie and
Larry were worried that the mechanical joints would resist
pipe bursting and build up in front of the tool. We had no
way of knowing for sure."
Additionally, the pipe was very shallow
in spots, sometimes as little as 20-inches below the surface.
Berry said, "It was a big concern especially in the parking
lot in front of the Pro Shop at the end of the driving range.
The lot had recently been re-surfaced and it was extremely
shallow in that section. We did not want to put in an unwanted
speed bump in their parking lot."
Finally, the rich clay soil posed a challenge
as well. Berry said, "That tool was going to have to
work hard to get through that good old Georgia clay."
The tool they decided to use for bursting the 1,000 feet of
water main was a 8.5-inch diameter Grundocrack Hercules pneumatic
pipe bursting tool from TT Technologies.
Teeing Off
Before the equipment was brought in,
Berry and his crew needed to establish the layout of each
burst. Berry had already determined that the job would need
to be done in sections, but the position of launch and exit
pits still needed to be determined.
Berry said, "We knew that somewhere
on the driving range was a tee for a 4-inch line that serviced
one side of the administration area. Unfortunately when we
were doing our locating, we determined that tee was in the
middle of one of the greens on the range." It would take
extreme care to prevent damage to the course. In order to
facilitate the lengths of HDPE pipe needed and minimize disruption,
the green would serve as the launch pit for two bursts.
Tri-Star went to great lengths to ensure
that no damage was done to the driving range, green, parking
lot and any other area at the facility. In order to protect
the area, Berry’s crew brought a truckload of 3/4-inch
plywood. The entire work area was decked with plywood to prevent
damage from crew members or equipment. In fact, a make shift
road of plywood was laid from the parking lot to the green
with the 4-inch tee.
After laying plywood around the green,
the sod was carefully removed and excavation began. In order
to keep the site as clean as possible, Berry’s crew used
Pel-bags to contain the soil.
Berry explained, "Pel-bags are large
canvas bags with buckle straps that hold approximately 1 cubic
yard of material each. After the bag is filled, it can be
moved to another location to minimize disruption. We used
the Pel-bags for storage and to prevent the soil from ‘contaminating’,
so to speak, the area."
The crew dug a launch pit measuring approximately
40-inches deep by 6-ft wide by 20-ft long. The long length
of this pit was needed to facilitate bursting in opposite
directions.
Exit pits were dug 650 feet away at Washington
Road and 350 feet away in front of the Pro Shop. The Washington
Road pit measured 40-inches deep by 5-ft wide and 10-feet
long. The exit pit in front of the Pro Shop measured 40-inches
deep by 6-ft wide by 8-ft long. That pit was dug in a small
flower garden area abutting a sidewalk.
With launch and exit pits complete, the
bursting equipment was brought in. 350-ft of 6-inch diameter
HDPE SDR 11 potable water pipe was fused together.
A 10-ton Grundowinch from TT Technologies
was secured at the exit pit in front the Pro Shop. The winch
provides constant tension and helps guide the bursting tool
through the run.
The Tee Shot
The Tri-Star crew positioned the tool
and started the air compressor and Grundowinch. Berry was
not only concerned about the mechanical joints, but the host
pipe’s shallowness worried him greatly on this portion
of the run, especially since part of the burst ran directly
under a section of stone wall that separates the tiered tee
boxes.
The tool entered the launch pit and began
moving through the pipe. According to Eddie Ward, the Grundocrack
Hercules was equipped with a bladed schnozz (guide head).
Ward said, "The purpose of the schnozz in this situation
is two-fold. First, it adds stability to the tool, helping
to maintain line and grade. Second, it focuses point pressure
and helps cut through difficult cast iron." It was also
hoped that the blade would help burst the mechanical joints.
The first few feet of the burst went
fine, until the tool reached the first mechanical joint. Berry
said, "It was moving along fine, but when it reached
that first joint it stopped. However, after 3 or 4 good piston
rams, the tool took off. It got to the next joint and slowed
up for 3 or 4 rams and took off again."
The burst went like clock work. There
was no crowning of the soil, no disruption and the stone wall
was still standing. The 350-ft burst took only 37 minutes.
The Tri-Star crew returned the next day to attempt the second
burst.
On The Fairway
The second burst ran from the center
of the green to Washington road. This burst was substantially
longer than the first burst running a total of 650 feet. Despite
the success the previous day, there was concern about the
increased number of joints they were facing today. Berry said,
"On the Hercules tool, we used a 10-inch rear expander
because we wanted to make sure we had plenty of tool to break
those joints."
The crew fused the length of HDPE pipe
for the second burst. The new pipe stretched from the center
of the driving range green, through the tee boxes, around
a group of giant oak trees, along a roadway in front of the
pro shop and onto the number one fairway. The tool was prepped
and lowered into the launch pit as a group of guests arrived
to watch the event.
A mechanical joint ring from the host cast iron pipe
is still visible on the tool at the end of the burst. |
The Gallery
According to Berry, exposure to pipe
bursting in this area is very limited. Berry said, "When
you mention pipe bursting most people in this area just scratch
their heads. When you explain the process, they believe you
even less. We decided to invite local and county engineers
to watch pipe bursting in action for themselves."
The Tri-Star crew launched the tool and 61 minutes later,
the 650 foot length of 6-inch cast-iron mechanical joint pipe
had been burst and replaced with 6-inch HDPE potable water
pipe. A large cheer erupted as the tool emerged at the exit
on Washington Road.
The 19th Hole
After seeing the pipe bursting results,
course grounds officials decided to burst additional lines.
Berry said, "Just before clean up began, we were asked
whether or not we could burst the 4-inch line that serviced
the administration buildings and upsize it to 6-inch. I said
no problem. We used the same tool and burst and upsized a
250-ft 4-inch line to 6-inch in about 45 minutes."
The Tri-Star crew cleaned up the site,
back-filled the launch and exit pits to the point where they
were barely noticeable. In fact, some were completely unable
to tell.
With their reputation intact and even
enhanced, Richard Berry and Tri-Star contractors have been
asked to come back to the tournament course during the next
off season and replace lines under portions of the Par 3 course.
Berry said, "By bursting cast iron
mechanical joint pipe, we did something that has never been
done before. To do it in such a highly visible place is remarkable.
We’ve made more believers in pipe bursting."
Trenchless Technology,
September 1999
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