overview
The design, surveying, and construction of a new tramline
for the bustling port city of Antwerp, Belgium, posed
many challenges for the surveyors of the multidiscipline
engineering and construction firm BAM Contactors. The
Noorderlaan (North Line) project included 6 kilometers
of track, two bridges and new car and train tunnels
connecting to an existing tram station. Adding to the
complexity was the excavation of a historic 14th-century
battlement: the "Spanish Wall." BAM preserved this
archeological treasure, incorporating pedestrian bridges
and viewing galleries into the project design.
Location
ANTWERP, BELGIUM.
TRANSFORMING THE WAY THE WORLD WORKS
THE CHALLENGE
The complex interfaces between old and new required
highly detailed surveys of existing features for the design
phase, and rapid as-built surveys during the construction
phase. BAM Contactors began the project using a mix of
conventional surveying, with their robotic total stations,
while a subcontractor collected point cloud data using
conventional high-end laser scanners. The engineers were
not satisfied with the scanning results: the issues included
large and unwieldy scans, poor registration to existing project
elements, and a slow turnaround for new scan requests. To
address these issues, BAM Contractor surveyors Niels Balens
and Johan Egerickx searched for a better link between point
clouds and other precisely surveyed data. They found it in a
new class of instrument: the recently released TrimbleĀ® SX10
scanning total station.
"We had to do a lot of small on-demand scans
for the engineers," said Egerickx. "They would
ask for new measurements in different parts of
the station, and we could go there, set up the
SX10, and perform a scan that was completely
registered in resection. We delivered this to the
engineers immediately."