construction. Every pier and tower
on the viaduct has a sensor to monitor
for vibration. There are also four
inclinometers in each slope to measure
movement.
Custom casing drive adapter
reduces waste and cost
ECA designed and fabricated a custom
casing drive adapter for Walsh to
facilitate overburden drilling. Dutton
PRECISION MONITORING FOR DEEP EXCAVATIONS,
TUNNELS, SENSITIVE STRUCTURES
AND INFRASTRUCTURE PROJECTS.
total stations
inclinometers
electrolevels
crack gauges
extensometers
vibration monitoring
“ONE ACCURATE MEASUREMENT IS WORTH MORE
THAN A THOUSAND EXPERT OPINIONS”.
Admiral Grace Hopper
905 822 0090 | www.monir.ca
watched as the operator of the BG 18
lowered the mast, inserted the adapter
into J-shaped notches in the casing and
began to seamlessly drill it into the soil
from the cab of the rig.
“We fabricated that at the Aldan
shop,” he said. “You need something to
transfer the torque against, so Walsh
cut those J-shaped notches in the top
of the casing.”
Vance says this innovation reduced
costs and eliminated wasted material.
“We pulled a lot of the casings out
as we drilled shafts, so we saved a lot,”
he said.
Bridging the gap between utility
and aesthetics
Walsh has demonstrated considerable
environmental sensitivity throughout
the project because of active involvement
by neighboring Swarthmore
College. Although SEPTA had the
right-of-way available for the viaduct,
it negotiated with the college to use
a necessary adjacent piece of land
instead of using Eminent Domain. In
addition to obtaining permitting from
multiple agencies, the contractor will
have to rebuild wetlands, replace up to
6,000 trees and shrubs, and reconstruct
a Stonehenge-esque circular formation
of Wissahickon Schist slabs, dubbed
“Crumhenge” by locals.
SEPTA will shut down service for
roughly 10 weeks during Summer 2016
to allow Walsh to install new girders,
bridge deck and catenary towers. Rail
cars will travel over the new viaduct
by Labour Day 2016. Walsh will conclude
the project by Summer 2017 with
demolition of the existing structure,
removal of the access road and restoration
of the site to original condition.
As SEPTA passengers, college students
and local residents admire the
towering modern viaduct that has
replaced the rusty, outdated structure
that once straddled this area of
natural beauty, the critical foundation
work performed by two drilling
rigs with custom tooling will remain
unknown. The folks at Walsh, ECA
and BAUER, however, will relish their
role in providing safe passage for
mass transit passengers and improving
the aesthetics of a critical piece
of infrastructure.
PROJECT SPOTLIGHT
The BAUER BG 18 H rotary drilling rig works in low overhead configuration to install drilled
shafts near the Crum Creek Viaduct west abutment with limited overhead clearance. Walsh
rented the BG 18 H and BG 20 H from Equipment Corporation of America to install eight
20- to 58-foot-deep, 36-inch-diameter drilled shafts at each pier and 12 at each abutment.
60 Q2 2016 www.pilingcanada.ca
/www.monir.ca
/www.pilingcanada.ca
