The current rehabilitation of the 2.2km-long Kaisermühlentunnel on the A22 Donauufer Autobahn in Vienna is a quite tricky task. The works are performed during the night and on the weekend in both tunnel tubes since September 2017. All works are performed under traffic which is quite challenging for the contractors. As general contractor for the electromechanical equipment, the ARGE A22 Kaisermühlentunnel consortium installs new lighting, ventilation and safety equipment into the tunnel. By these measures, Austria’s high-level road operator ASFINAG improves the safety of Austria’s most frequented tunnel. Recently, fire tests have been performed to prove the functionality of the new ventilation system.
Austria’s most frequented tunnel
The Kaisermühlentunnel is a two-tube, 2.2km-long city tunnel with accesses, exits and collectors. It is located between the Kaisermühlen interchange and the Brigittenau bridge and was built as a noise protection tunnel between 1985 to 1989. From 1993 to 1996, it was extended by covering the Autobahn between the Marshallhof and the Donau City. 120,000 vehicles pass the Kaisermühlentunnel every day which makes it the most frequented tunnel in Austria. As the tunnel is a connection to the oil harbour Lobau a large portion of the traffic are heavy vehicles. The Kaisermühlentunnel is monitored around the clock by ASFINAG operators in the regional ASFINAG traffic control traffic management centre in Inzersdorf.
Fire tests to prove the functionality of the new ventilation system
On 26 June 2018, the functionality of the new ventilation system was tested by fire tests. 50 litres of fuel were set on fire in the Kaisermühlentunnel. This equals the intensity of fire and smoke generated by a burning car. The fire brigade tested four scenarios in the 2.2km-long Kaisermühlentunnel.
ASFINAG managing director Andreas Fromm says: “All major Autobahn tunnels have to pass such fire tests.
“These tests look spectacular however are essential for the safety during an incident.”
The most important thing: latest after 90 seconds the tunnel control system has to localise the fire, automatically start the ventilation system and close the tunnel for traffic. The Kaisermühlentunnel is equipped with in total 40 jet fans. During a fire, these jet fans transport the smoke out of a tunnel in the direction of the traffic with a velocity of about two meters per second. This requires a sophisticated measurement of the air velocity and direction.
JES as reliable partner for tunnel environmental monitoring
Austrian road operator ASFINAG spends about €40 million for new operational and safety equipment of the Kaisermühlentunnel. The partners of the consortium ‘ARGE A22 Kaisermühlentunnel’, EQOS Energie Österreich GmbH and ECOexperts Automation GmbH, have chosen JES as partner for the enviromental monitoring equipment in the tunnel. We could recently finish our works in the Kaisermühlentunnel where we installed and commissioned:
- 18 Luminance meters t/LUM-A
- Seven extractive CO and visibility monitoring systems t/EXT
- 40 Air flow monitoring systems t/FL-US
“We are honoured that we once again equipped the most frequented tunnel in Austria. As for all other contractors the conditions of working only at night and under traffic were challenging for our staff. The more we are delighted that our systems – as usal – have performed reliably during the fire tests,” says JES managing partner René Jung.
