Singapore - Trenchless International
Singapore - Trenchless International
Singapore - Trenchless International
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
PROjeCts<br />
October 2010 - <strong>Trenchless</strong> <strong>International</strong><br />
34<br />
A 1.8 m diameter Robbins Rockhead is<br />
boring an unprecedented seven sewer<br />
tunnels in Ohio, US.<br />
Robbins rocks through seven<br />
Indiana, US contractor Midwest Mole Inc had a daunting task ahead of them when they were<br />
named General Contractors for not one, but seven sewer tunnels, tackling the unprecedented<br />
bores with Robbins Rockhead.<br />
WITh each TuNNeL varying in grade and<br />
the route travelling through interbedded layers<br />
of shale and limestone, ranging from dry<br />
conditions to wet, sticky ground.<br />
Despite the highly changeable conditions,<br />
Midwest Mole chose a single machine<br />
solution for the pipeline, totaling 2,874 m<br />
in length.<br />
the contractor is utilising a 1.8 m diameter<br />
Robbins Double shield Rockhead to excavate<br />
the tunnels, ranging from 249 – 614 m<br />
long, for the shayler Run segment C sewer<br />
Replacement Project in Clermont County,<br />
Ohio, Us. the $Us15 million project will<br />
upgrade severely degraded sewer systems<br />
and protect the area surrounding environmentally-sensitive<br />
shayler Creek.<br />
Project background<br />
the shayler Run segment C project is a<br />
priority for the project owner, the Clermont<br />
County, Ohio Water Resources Department,<br />
because of severe pipeline erosion in the<br />
creek bed.<br />
sanitation Engineer for the Clermont<br />
County, Ohio Water Resources Department<br />
Lyle Bloom said “the existing sewer pipe<br />
was installed in 1978 directly into the creek.<br />
since then, the creek has eroded, exposing<br />
the pipe to the environment and putting<br />
certain sections at high risk of failure. the<br />
exposed pipe has now dumped raw sewage<br />
into the creek on several occasions.”<br />
the new pipeline will be installed well below<br />
the creek bed, crossing the creek a total of<br />
seven times. the route cover ranges from 3 to<br />
30 m, with the majority of the pipeline running<br />
some distance from the waterway.<br />
Final carrier pipe will consist of 1 m<br />
diameter HOBAs reline, and will be much<br />
larger than the current 600 mm sewer line.<br />
“the larger pipe was decided on mainly<br />
to allow trenchless construction, though it<br />
has the added benefit of providing a larger<br />
capacity for future needs in the area,” said<br />
Mr Bloom.<br />
Pipeline construction consists of seven<br />
tunnels criss-crossing the creek, each connected<br />
by a 9.7 m diameter launch and<br />
receiving shaft, with a total of eight shafts<br />
in all. the shafts will eventually become<br />
fiberglass manhole structures to access the<br />
new pipeline.<br />
Due to the gravity sewer construction,<br />
each tunnel is at a slightly different grade to<br />
maintain specified slope.<br />
Vice President of Operations at Midwest<br />
Mole steve Abernathy said “We needed<br />
a machine that could hit the specified<br />
manhole locations within a foot of line at<br />
1.3 – 2 per cent grade.”<br />
choosing the machine<br />
the nature of the extensive gravity<br />
sewer made the machine selection all the<br />
more challenging.<br />
The Robbins Double Shield Rockhead<br />
completed its first of seven tunnels at rates<br />
of up to 32 m in 24 hours.<br />
The Robbins Double Shield Rockhead is<br />
boring and installing a primary liner of steel<br />
ring beams and lagging every 1.5 m.<br />
US Contractor Midwest Mole is boring seven<br />
sewer tunnels to upgrade severely corroded<br />
lines in environmentally-sensitive Shayler<br />
Creek.<br />
New Online Advertising<br />
packages in<br />
www.trenchless-australasia.com<br />
• Great value packages offering exposure<br />
on websites & e-news<br />
• Huge discounts on offer for multiple bookings<br />
• Fully audited readership and performance<br />
figures for advertisers<br />
Online advertising – a great way to support your print<br />
advertising and target new readers.<br />
Contact David Entringer – dentringer@gs-press.com