The worksite is 300 metres long and 18 metres wide. The
flurry of activity around the worksite demands painstaking
staging and sequencing. “It is probably one of Toronto’s
busiest intersections in terms of pedestrian and traffic flow,
so that brings its own challenges with respect to how we
plan and execute our work in a safe and efficient manner,”
said Morrisroe.
Keller brings innovative techniques to the project
Keller’s 30-metre-deep secant pile wall composed of 8 MPa
concrete provides excavation support to facilitate the construction
of the station. The secant pile wall will also function
as a water cut-off wall which will significantly reduce the
need for dewatering across the entire site.
Deviation control monitoring devices have been outfitted
to each of the Liebherr LB 36 drill rigs used for constructing
the secant pile wall. Developed by Jean Lutz, the deviation
control monitoring device measures the verticality of the
holes. The sensor measures the rotational trajectory of the
auger throughout the depth of a cased hole to generate threedimensional
coordinates for analysis.
“After we measure the verticality, we use that information
to develop a 3D model in order to ensure we have sufficient
interlock along the full depth of the pile,” Morrisroe said. “If
COVER FEATURE
28 Q4 2018 www.pilingcanada.ca
/www.pilingcanada.ca
