Tunnel vision

By Zoltan Pap

Concluded on 21 November 2007, the Concession Agreement project includes the financing, construction, operation and maintenance of the M6/M60 Motorway within the framework of a Public Private Partnership. A special feature of the 80km M6/M60 Motorway is the tunnel chain, which is unique in Hungary and consists of four tunnels with viaducts between, totalling a length of more than 5km.

The concession company (shareholders Strabag AG, Colas SA, John Laing Infrastructure and Intertoll-Europe) successfully delivered this section of motorway in Hungary to very stringent programme by the end of March 2010. This achievement was made possible by all stakeholders participating in the efforts to deliver their respective share, including the public sector participation.

The implementation of the tunnel chain, taking into account the total length of tunnels and viaducts, site conditions and lack of local staff with relevant experience, represented a challenge from both a construction and an operational point. The special purpose operations company established for this project, Mecsek Autópálya Üzemeltető (established by Intertoll, Colas and Strabag), has a dual role: to deliver the motorway and tunnel management systems, and routine operations of the project road.

The operational activity on the open road is similar to other Hungarian motorways and includes routine and ad hoc maintenance works and winter operational tasks in which Intertoll has decades of international experience. The major challenge was the operations and maintenance of the tunnel chain.

The centre of the tunnel operations is the control room in the Operations and Maintenance Centre located in Bátaszék. This room, with the state-of-the-art video wall and central control units, is the nerve centre of the tunnel operations. The operations controllers are on duty in the control room on a 24/7 basis, 365 days of the year, monitoring the tunnel traffic and the technical status of equipment ready to intervene to safeguard the road users and infrastructure, if required. To ensure their support, road patrols and a team of system technicians, electricians and repairmen is also available.

Based on a pre-determined emergency plan; in the event of an emergency automatic sequences shall start the necessary control processes in the SCADA system to aid the operators. The basic concept for developing the motorway management equipment system architecture was to form a unified integrated information system for sub-system equipment on the open road and in the tunnels. The objective was operational continuity through redundancy combined with ease of operation and maintenance with optimised spare parts management.

Data from the roadside equipment is transferred to a data control unit located near the installation point, from there via fibre optic backbone to the central data unit and then to two geographically separated redundant servers. A redundant optical ring network is installed in the tunnel chain section to ensure uninterrupted communication.

The emergency Call System includes SOS call boxes every two kilometres along the motorway, and every 150 metres in the tunnels. There are also emergency panic buttons every 50 metres. A meteorological subsystem provides measured data from the road that supports the winter maintenance.

CCTV cameras installed both on the open road and in the tunnels provide continuous visual cover and record video streams automatically in case of an emergency. Traffic Logging Equipment installed at nine locations along the road performs counting and classification of vehicles provides required traffic data. In addition, two of these sites are equipped with High Speed Weigh-in-Motion sensors to provide statistical information about overloading. TLE in tunnels monitors for dangerous traffic conditions.

Optical Height Gates are installed ahead of the tunnel portals to detect vehicles that are above the height limit of the tunnels and enable the operator to prevent such vehicles from entering the tunnels by the means of traffic lights and variable signage alerts. Additional features include ventilation system jet fans installed in tunnels longer than 500 metres and controlled automatically, taking into account wind velocity, visibility, CO2 levels and any potential fire hazard.

Biography

Zoltán Pap is Project Development Director of Intertoll Europe, an independent toll and motorway infrastructure developer and operator -a wholly owned subsidiary of Group Five, a major construction group in South Africa. Zoltan has been involved in developing motorway concession projects since the mid nineties. After working for Intertoll overseas he joined Intertoll Europe in 2001.