Smart Industry 1/2017

photo ©: Hajo Dietz, Nürnberg Luftbild
Norway has more than 1,800 road
bridges nationwide and many are
located in the countryside far from
any large city. UAV systems builder
Orbiton, based near Lillehammer is
using drones to inspect these remote
sites. The company's technical director
Gonzalo Figueroa says drones make
inspections easier and cheaper without
disturbing daily traffic.
Statens Vegvesen, the Norwegian
public road authority, has contracted
Orbiton to conduct regular inspections
on 80 bridges in the Østlandet
region of Eastern Norway, which
includes the capital city of Oslo.
Prior to 2015, inspections were done
with the help of what Gonzales calls
"snooper trucks" – vehicles with a
flexible crane to move an inspection
engineer alongside and underneath
the bridges. The vehicles are expensive
to buy and costly to maintain. They
also cause massive road obstructions
so signs need to be erected and staff
allocated to direct traffic – in many
cases the bridge must be closed
down completely for inspections that
can take hours. Consequently, the
work was often conducted at night,
which made it even harder to detect
problems.
Using inspection drones provided by
Ascending Technologies, a German
manufacturer, allows Orbiton to do the
work during daytime hours without
causing any disruption. Instead of
needing a team of seven to 10 specialists,
a bridge can now be inspected by
two staff, and in much less time.
Fixed sensors
Doing regular inspections at lower
cost and with a higher frequency will
help detect failing structures earlier.
An even better idea, many believe,
is to install sensors on the bridges
themselves and thus be able to collect
information about structural problems
directly and around the clock.
Bird's eye perspective: Though the top-view gives no hints of it, this is an intelligent bridge.
An even
better idea
is to install
sensors in
the bridges
themselves
and collect
data around
the clock
Sensors are like eyes
and ears
Some examples for the
integration of sensors into
the “smart bridge”
To this end, the German Ministry for
Traffic and Digital Infrastructure (BMVI)
launched a Smart Bridge project
last year under its Digitales Testfeld
Autobahn (Digital Highway Field
Test) initiative. The first ‘intelligent’
bridge was opened for traffic near
Nuremburg in Bavaria last October.
The so-called Smart Bridge connects
two motorways and sensors provide a
constant stream of information needed
to evaluate its status. Three types
of sensors are required to monitor
and analyze elements that may affect
the bridge: structural integrity, traffic
patterns and usage.
The Universität der Bundeswehr
München (German Federal Armed
Forces University, Munich) in cooperation
with Maurer Söhne, an
engineering company also based
in Munich, developed an Intelligent
Track Transition module for the project.
These high-end sensors are fitted
inside the bridge’s expansion joints
to detect vehicle speed, weight, the
number of axles and the distance between
them. The system can use this
data to dynamically calculate axle
loadings.
The Smart Bridge project also includes
Intelligent Sensor Networks
being developed by the Institute of
Telematics at the University of Lübeck
to monitor the bridge structure. In
addition, a road traffic management
system developed in the city of
Weimar by the Bauhaus University and
civil engineering firm Ingenieurbüro
Freundt will gather further traffic data
for the analysis.
Together the systems build a digital
model of the bridge in real time by
transferring the data by Wi-Fi locally
for testing and calibration. The data
will then be beamed over the internet
to scientists and maintenance crews
using web-based interfaces to view
and analyze the collected data in realtime
using evaluation algorithms.
The current evaluation is expected
to take at least five years and the
Federal Highway Research Institute
(BASt) has high hopes for transferring
and applying the results of the test to
other new bridge projects as well as
to existing structures.
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