ABSTRACT
When considering the main challenges of the ecological transition in underground structures, several points of view are possible. First, the underground structure can be seen as part of the transportation infrastructure and can therefore be one of the solutions to reduce the carbon intensity of transportation and achieve a more sustainable mobility. Besides, it may also refer to underground space offering new opportunities in terms of usages for the sustainable city. Whenever possible, multifunctionality, resilience and mutability should be part of the design criteria. Finally, the ecological transition must also be at the heart of the design, construction and operation of underground structures, by reducing the carbon footprint and the consumption of natural and energy resources. This article intends to develop and illustrate all these aspects, which might form the bedrock of a certain vision of the ecological transition in tunnels and underground spaces.
