Tunnel tube closing systems such as traffic lights and road barriers, air ventilation, lighting, safe escape routes… Wibo Tienstra knows all too well that constructing a tunnel involves a lot more than merely installing tubes and laying asphalt. “A wide variety of technical installations for the tunnel and traffic are procured, and they have to communicate properly. In a way that, for example, the air ventilation is activated during traffic jams, and that the drainage systems work adequately when it rains. All aimed at a fast and safe traffic flow for the road user.”
However, in reality it’s not as simple as the impression that Wibo is giving. Every possible scenario – traffic jam, a stranded truck due to a breakdown, fire – everything is scrutinised right down to the finest detail. “Software and systems engineers have to think of everything, and make sure that the systems communicate properly so that everything that needs to happen in a certain situation, happens in exactly that way in order to guarantee the safety of traffic in the tunnel. This makes the project so complex and challenging. It’s important that the software is programmed in a way that the systems function correctly at all times and in every possible situation: during ordinary traffic, in maintenance mode, during calamities, and when the tunnel needs to be evacuated.”
“People with affinity with both technology and programming can eat their heart out in tunnel construction projects.”
Safety first, and before everything else. For IXAS, the contractor combination that builds the tunnel on behalf of Rijkswaterstaat, that means testing, testing and once again, testing. As a first step, the employees of ICT Group run separate tests of the hardware and software (control system) of the technical installations of the tunnel and traffic (FAT phase). Are they functioning properly? Do they meet the requirements as defined? This is followed by the realisation phase, when all technical products are installed and interconnected, and the system is commissioned (IBS). During this phase the system is put under pressure, and extensive checks are performed. During and after the commissioning phase, the system is checked again (SAT phase). Is everything still functioning properly in the new situation? Are the signals arriving in the way they should? Can the systems communicate with one another in an integral manner? The iSat phase consists of tests that check whether the system’s actions are in line with what has been programmed. So in the case of a fire: is the tunnel closed for approaching traffic, is the air ventilation activated and are the traffic users receiving instructions with regard to what they should do? The last step, the SIT phase, consists of testing the technical system in combination with the business processes of the traffic controllers.
Switch board role
As integration manager of ICT Group at IXAS, Tienstra says he has a finger in every single pie, and knows a little about everything. “That’s important. You have to understand how the installations work, what they do and what they are needed for.”
It is expected that the first cars will be driving through the Gaasperdammertunnel in 2020. ICT Group provides a part of the software for the tunnel technical installations and participates in the testing of the systems.