Linking the shaft to the line 15 South tunnel, the teams excavated two underground galleries for seven months.
In 2019 the construction process of the University structure commenced in Créteil, with the construction of the underground walls and the boring of the interior space. In 2021 building of the floor, called the raft, at a depth of 31 m completed and gave way to the digging of the branches.
Responsibilities of these two galleries, which are 10 and 18m long and have been excavated from the bottom of the structure to the tunnel using mechanical shovels, will be connecting the structure to the tunnel of line 15 South, as well as providing ventilation and smoke extraction from the tunnel, and facilitating emergency access and maintenance of the structure.
The construction of the six levels of the interior space of the structure has now been underway since February.