Life cycle of tunnel equipment

The increasing variety of tunnel equipment means that life cycles may vary considerably from one type of equipment to another.

Some equipment may have a lifespan of more than 20 years (power supply, ventilation ...); others will only last a decade or so (notably equipment with a lot of electronics). For some, its lifespan may even be less than 10 years.

It is therefore essential to examine the lifespan of each family of equipment, with particular attention when this lifespan is low (10 years or less). The purpose of this review is to identify the factors that have a strong influence and that can be acted upon to ensure the lifespan of the product, or even improve it.

It is particularly useful to take into account factors such as temperature, humidity, mechanical stress and the environment.

A life cycle analysis can be conducted at different stages of the life of a tunnel (and its equipment):

• Preliminary design phase,
• Design phase,
• Construction and commissioning phase,
• Operation phase,
• End of operation phase.

Technical reports 2016R01 “Best practice for life cycle analysis for tunnel equipment” and 2012R14 “Life cycle aspects of electrical road tunnel equipment” provide further information on this issue.