International activities

Although the COB focusses on subterranean construction in Dutch soil, some of our projects are also interesting for other countries. We have had several international visitors (China, Singapore, Belgium…) and we are keen to participate in events as the World Tunnel Congress. On this page you will find some general information about the COB and more details about our international projects.


The COB is a network organisation, a foundation with more than sixty affiliates, all involved in subterranean construction and the use of subterranean space. The network includes consulting engineers, construction companies, public authorities and knowledge institutions.


The COB’s philosophy is that the use of subterranean space provides an essential contribution to making the Netherlands attractive, sustainable and a pleasant place to live. Subterranean construction creates value. The COB therefore wants to create a positive development climate for the use of subterranean space, so that the exploitation of the underground becomes a logical part of spatial planning. The costs of subterranean construction are often off-putting, but there are great returns to be achieved in terms of sustainability, space and quality enhancement.

The square in front of Rotterdam Central Station is an enjoyable environment due to the underground parkings (car and bicycles) and tunnels (car and subway).

What and how

The COB collects, develops and provides access to knowledge about the subterranean use of space. This is done by constantly surveying what issues are current within the network and within Dutch society. The COB then initiates and supervises projects which help to solve the problem which has jointly been identified. The broad composition of working groups means that all relevant aspects of a problem are considered. The knowledge that is acquired belongs to everyone and can be used by everyone. The participants within the COB are not competitors, but work together on a solution. The result is shared across the network, by recording it in publications and presenting it at meetings, within training courses, on the website and in the magazine De Onderbouwing. However, participation itself is already one of the most powerful ways of developing and embedding knowledge.

At the World Tunnel Congress 2018 in Dubai

Three research projects of the COB-network were presented at the WTC2018 in Dubai:

  • Tuesday 24th, Sheikh Maktoum A, 2:20-2:40 PM – Karin de Haas, Long-term vision and working program on tunnels in the Netherlands
    >> Download the presentation (pdf, 3.4 MB)
  • Tuesday 24th, Sheikh Maktoum B, 2:40-3:00 PM – Paul Janssen, Working towards a zero-energy tunnel – technical, contractual and process solutions
  • Each conference day from 3 PM you could visit the poster presentation of Hans de Man about the digital tunnel twin

In collaboration with BESIX and KIVI, the COB hosted a small network event at the WTC in Dubai on Tuesday 24th from 5 to 7 PM. At this gathering the guests talked some more about the topics of our presentations: digital tunnel twins, tunnel renovations, energy reduction and long term visions on tunnels.

International projects

Future perspective on tunnels

The position of tunnels in their immediate environment and their network is changing, the issue of sustainability is coming to the fore and increasingly higher demands are placed on the reliability, availability and noise levels of tunnels throughout their entire life cycle. In 2016 the COB-network developed a long-term vision as a guideline for clients and contractors. In the period from January to September 2017, the COB network, together with external experts, translated that vision on tunnels into concrete goals and an integrated programme.
>> Download the long-term vision on tunnels in the Netherlands (pdf, 660KB)
>> Download the tunnel programme (pdf, 1.5 MB)

CSI for tunnels

Worldwide, renovation of tunnels is becoming a huge challenge. Due to the large costs and the need for accessible infrastructure, choices need to be made as to which tunnels will be renovated first, which renovations can be postponed and what should be the scope. Unfortunately, we lack the knowledge to develop a proper asset management strategy for tunnels. The ambition of the COB is to make a first step by establishing an overview of the ten key risk areas and the extent to which we currently have control over those risks. This project will be part of the tunnel programme (see above).

Presented at the WTC2017 in Bergen, Norway:
>> Position paper (pdf, 980 KB)
>> Discussion notes (pdf, 440 KB)

Energy reduction in tunnels

In 2016, experts within the COB-network have developed a (Dutch) catalogue with technical, contractual and process measures to reduce the amount of energy consumption in tunnels. The results are summarized in an English paper and discussed with international experts at the World Tunnel Congress in Bergen, Norway in 2017. The paper was also presented at the STUVA Conference 2017 in Stuttgart, Germany.
>> English paper (pdf, 580 KB)
>> Discussion notes (pdf, 480 KB)