The fine-tuning of the M85 tunnel is on track

As we reported in our July article, the SDD Konzorcium was completed on the final section of the M85 expressway, with a tunnel built near Sopron.

The consortium of Dömper Kft., Subterra-Raab Kft. and Pannon-Doprastav Kft. has built a 780 m tunnel pair - with two lanes per tunnel - on a 4.2 km section between the Fertőrákos junction and the border with Sopron. This time, we present the Építési és Közlekedési Minisztérium project with a photo report and a technical report, while also highlighting the interesting aspects of the trial operation for the rest of the year.

The track structure was sealed by a 26 cm thick layer of basalt concrete

We last wrote about the development in February, when we reported that structural work had been completed in both the north and south tunnels. After that, the track structure could be completed in both tunnels: „A 30 cm layer of FZKA, a 17 cm thick Ckt-4 hydraulic binder base layer and a 4 cm thick AC-11 separating asphalt layer were installed in the counterfort,” said project manager Attila Kerékgyártó.”

Finally, the 26 cm thick CP4/2.7 basalt concrete, which required a special machine chain to lay the top layer of the track structure, was laid, and was completed in May. "The final coating system has been applied to the masonry of the north and south passages up to a height of 5 metres," added the project manager.

In addition to this, the final construction of the track structure of the expressway connecting the eastern and western sides of the tunnel to the tunnel lobby was completed, as well as the noise barrier and planting works, among others.

Fans, lighting bodies and emergency call boxes installed in the tunnel

The equipment needed to operate the tunnel also gave the contractors a major task. "In the last period, the horizontal and vertical systems for traffic control and management of the tunnel have been installed and wired, and all JET fans have been installed after the field test," said Attila Kerékgyártó. "The final lighting bodies, the active prisms have been installed and the special gateway for the emergency exits has been installed and wired," he added.

In addition, emergency booths were set up in the tunnel. The electrical distribution cabinets for these have been armed and a special door for the cabins has been installed.

In addition to this, live testing of the integrated traffic engineering and control elements has been carried out pending the completion report. The tunnel management software, the SCADA revival and the complex operational test of the system components have also been completed. The consortium also prepared the implementation plans and certification documents.

Entry into service expected in December

The project leader also reported that the technical handover was successfully completed on 1 July, after which the trial operation could start. "As the future operator of the tunnel, Magyar Koncessziós Infrastruktúra Fejlesztő Zrt. will test the system that has been built," he said. "It will also train and train the operator colleagues so that they can carry out their tasks with the appropriate skills and routine."

This phase is said to take about 4-5 months, with the launch expected in December.

A total of 122 traffic situations are run in the tunnel

He also gave details of the tools that will be tested during this period. These include

• cameras (28 event detection cameras, 4 dome cameras, 2 fixed cameras);
• emergency and fire buttons and emergency telephones;
• envelope temperature indicators;
• traffic counters and optical altimeters;
• sensors to monitor air quality;
• fire water network with reservoir with pressure regulator, fire hydrants;
• a drainage system with a damage control hive;
• speakers;
• active pavement reflectors and service lights (traffic management);
• LED traffic management signs and lane occupancy signs;
• LED luminaires for lighting;
• and ventilation fans are tested.

A total of 122 traffic operation conditions are modelled according to the so-called traffic management matrix:

the tunnel is tested in specific traffic situations such as congestion, accident, lane closure, speed reduction, arrival of an oversized vehicle, pedestrian in the tunnel, power failure or fire.

All of the devices listed above are integrated into the so-called SCADA system, which manages the tunnel: all data from the subsystem is fed into this system. The operation and monitoring of the tunnel is carried out from the plant engineering office in Nagycenk.

The disaster management simulation exercise will also take place

The project manager stressed that the trial run will not only test the operation of the above-mentioned devices in the system. "The operating staff is also being trained to be able to react in a timely and appropriate manner to all situations and incidents that may arise, in a routine manner, with the involvement of partner agencies, including the emergency services, the police and the ambulance service."

The trial operation will also include a simulation exercise by the emergency services involving the tunnel safety officer.

He pointed out that the construction consortium also has an important role to play in this process. As the developer, supplier and contractor of the system, they are available to support the process during the trial run. "We will correct any faults and make any changes requested when fine-tuning and parameterising the system's operation for the operator."

It reaches, and in some cases even surpasses, the operational level of tunnels in its western neighbours

In response to a question, Attila Kerékgyártó described the tunnel management system as a complex whole.

"To highlight any one part of it is pointless, no one is more important than the other. There are so many elements that build on each other in terms of perception, signalling and operation."

He stressed that the sensor and control system and traffic control automation developed reaches the level of operation of the tunnels of our western neighbours, and in some cases even surpasses it. "All the systems installed and their sophistication could safely control the operation of a much longer tunnel."

Not much previous domestic experience available

He pointed out that the biggest challenge in the design and construction was,

We do not have much experience in Hungary in the field of regulation, implementation and operation, so we had to implement a number of international examples and experiences to complement the existing ones.

"This not easy start was made more difficult, or rather more exciting, by the fact that in the middle of the construction there was an operator change - the Magyar Közút was replaced by the MKIF - in the life of the tunnel, which resulted in quite a few operational differences."

Fine-tuning the system is on the right track

In conclusion, Attila Kerékgyártó summarised the experience of the first month of the trial operation by saying that the fine-tuning of the system is well underway. "The MKIF is quickly and efficiently mastering the operation of a complex and intricate mechanism; emergency services present are consciously and purposefully testing the complete control technology of the tunnel. We can be confident that after the successful completion of the trial run, which lasted several months, and with the operating licence and the traffic permit, road users will be able to use the new section of the M85 motorway, including the 780-metre Vienna-Domb tunnel pair, by the end of the year."