Expanding Underground. Knowledge and Passion to Make a Positive Impact
on the World – Anagnostou, Benardos & Marinos (Eds)
© 2023 The Author(s), ISBN 978-1-003-34803-0
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Increasing the capacity in long railway tunnels through
combination of railway operation control and tunnel control
Sebastian Klabes & Markus Pichler
Siemens Mobility AG, Switzerland
ABSTRACT: Ambitious tunnel projects are currently being carried out all over the world to
increase capacities, shorten travelling times and strengthen railway transport in its competi-
tion. Especially, in long railway tunnels, critical events, which might quickly turn into
a disaster, shall be avoided at any time. A crucial factor is effective supervision and fast
response of the railway operator (dispatcher). The optimized interaction of the tunnel control
system and the railway control system support the railway operator (dispatcher). Siemens
Mobility delivered both systems for the 57 km long Gotthard base tunnel, which started com-
mercial operation in 2016. Considering experiences during the project execution and the cur-
rent operational experience we will show how the overall capacity can be increased by
combining railway operation control and tunnel control. We will illustrate this exemplarily by
discussing an operational risk of railway operation in long tunnels. We show, how the fast
and effective reaction of the railway operator (dispatcher) enables to manage the operational
In long railway tunnels, it is important to avoid situations that endanger the safety of the
people passing through. Events that deviate from normal operation are detected at an early
stage through optimized interaction between the tunnel control system and railway control
technology and optimized with our tunnel automation system. This allows safety-relevant situ-
ations to be avoided before they become a greater danger.
Siemens Mobility supplied the tunnel and rail control technology for the 57-kilometre Gotthard
Base Tunnel (supplied by Yunex Traffic, formerly Siemens Mobility), as well as the tunnel auto-
mation system. We have acquired unique know-how with the experience we gained during the
project phase and during the tunnel’s operation since 2016 (Siemens, 2022, SBB, 2022).
More and more ambitious tunnel projects are being realized worldwide (Wikipedia, 2022).
The issues are travel time reductions, capacity increases and ensuring the competitiveness of the
rail system. Alongside these aspects, however, tunnel safety always comes first (SBB, 2022).
2 THE SOLUTION FOR SAFE AND EFFICIENT OPERATION
The tunnel control technology and the tunnel automation system enable direct communica-
tion between the tunnel technology (e.g., ventilation, drainage, fire protection, gates, traction
current, communication, etc.) and the railway control technology (Traffic Management
System, Iltis railway control technology, signaling and RBC).
All the systems necessary for incidents (Emergency Response System), train operation (Train
Control System) and maintenance (Maintenance Management Tool) are integrated into the
Tunnel Control System, based on Siemens SCADA system WinCC OA, allowing the systems to
exchange relevant notifications and information with each other directly
Figure 1. With our solution, the data from the tunnel control system and the tunnel automation system
are exchanged and efciently processed for the safety of tunnel operation.
3 CONCENTRATION ON THE ESSENTIALS
In addition to tunnel control technology, tunnel automation is an important component of
our intelligent solutions. Detailed predefined scenarios for normal operation, maintenance
and malfunction are automatically selected and made available to the operating personnel for
selection as a “tunnel reflex”.
For example, longer distances between vehicles after hazardous goods transports or com-
plex scenarios such as lane changes including operation of the fire protection gates, ventilation
and lighting can be provided and activated at the click of a mouse. Staff can focus on problem
solving, any necessary rescue measures and a quick return to normal operation.
4 COMPREHENSIVE APPROACH – MORE CAPACITY AT THE SAME LEVEL OF
Predefined scenarios and suggested actions (tunnel reflex) in the event of incidents are very
important for the Gotthard Base Tunnel. Their starting point is the monitoring of rail traffic by
the Train Control System. The Train Control System detects any malfunctions and commui-
cates the corresponding data as a «tunnel reflex» to all relevant systems, which then commence
automatically running through all possible scenarios for managing the situation. For example:
emergency ventilation systems in the tunnel are activated, lights are switched on at the emer-
gency stop closest to the affected train and the emergency doors at that stop are opened. If
necessary, further actions may be taken, for instance draining the storm water reservoir at the
north or south end so that it will be available to hold contaminated run-off from firefighting
operations. Additionally, it might be necessary to switch over the ventilation of the tunnel’s
technical rooms to prevent smoke from damaging the equipment. The Tunnel Control System
monitors the emergency procedures and ensures they are carried out correctly in such emergency
scenarios. For this purpose, it also initiates timekeeping checks and monitors the individual
steps. If these are not performed automatically and correctly, the system informs the operator.
The Emergency Response System, which is part of the Tunnel Control System, also
launches all other measures necessary for managing the emergency. Specific information and
decision-making steps are stored in the system and can be utilised in line with the situation.
They help the emergency operations manager decide who needs to be alerted in an emergency,
such as the police, fire and/or ambulance services. The system also allows easy monitoring of
the intervention areas.
The risk reduction is illustrated in Figure 2: Due to the boundary conditions and natural
restrictions of tunnels the risks must be mitigated in a stepwise approach. The combination of
tunnel control system and tunnel automation reduces the risks (green horizontal arrows) on
every reduction level according to EU Safety in Railway Tunnels Technical Specification of
Interoperability (European Commission, 2014): prevention, mitigation, evacuation, and
This increased risk reduction allows for higher unmitigated risks (e.g., more trains in the
tunnel) by keeping the same acceptable residual risk. Efficient operation with minimized restric-
tions for the operator is enabled. We will illustrate this in a video presentation during our talk.
Figure 2. Risk reduction in tunnels according to EU Safety in Railway Tunnels Technical Specication
of Interoperability (European Commission, 2014).
The coupling of tunnel control system and tunnel automation implements an advanced deci-
sion support system that supports the railway dispatcher and reduces risks through pre-
defined dispatching scenarios (tunnel reflexes). As Siemens’ experience with the Gotthard
Base Tunnel shows, it allows operation at higher capacity at the same safety level. Higher cap-
acity enables a more economic use of long railway tunnels.
SBB, 2022, The Gotthard Base Tunnel. SBB Website (https://company.sbb.ch/en/media/background-
information/gotthard-base-tunnel.html accessed 2022/11/29)
Siemens, 2022, Adventures? Not in the Gotthard Base Tunnel, Siemens Global Website (https://new.sie
mens.com/global/en/products/buildings/references/gotthard-base-tunnel.html accessed 2022/11/29)
Wikipedia, 2022, List of longest tunnels, Wikipedia website (https://en.wikipedia.org/wiki/List_of_lon
gest_tunnels accessed 2022/11/29)
European Commission, 2014, Commission Regulation (EU) No 1303/2014 of 18 November 2014 con-
cerning the technical specication for interoperability relating to safety in railway tunnels of the rail
system of the European Union, Ofcial Journal of the European Union and available in EUR-Lex