Paris Métro Line 11 currently connects Châtelet, at the heart of Paris, to Mairie des Lilas.
The construction of the line 11 extension from Mairie des Lilas to Rosny-Bois-Perrier will be controlled by STIF and RATP, co-supervisors for this section.
The GC03 lot of this extension comprises the construction of a 250-meter tunnel between the existing Atelier des Lilas railway depot (current eastbound terminal of the line) and the Serge Gainsbourg station, currently under construction.
The tunnel is to be excavated by means of the conventional tunneling method, hence by removing soil while inserting steel HEB profiles and sprayed concrete in order to withstand the soil pressure.
Enser, through its subsidiary Enser France, was involved in the detailed design of the concrete tunnel and was also responsible for the realization of all the execution plans of steel temporary profiles, tunnel-face stabilization and pipe umbrella system.
Due to the rail track variability, both in plane and in elevation, it immediately seemed that the manual insertion of all the elements by respecting the tight tolerances involved, was a time-consuming process.
Enser therefore decided to develop a tailor-made Grasshopper file, by using the live-link between Tekla Structures® and Grasshopper, in order to automate the process of placing all the elements correctly aligned with respect to the rail track.
The Grasshopper file included a coordinate transformation (i.e. rototraslation of the reference system) which permitted both to have all the structural elements in Tekla close to the origin of the model, but also to give the georeferenced coordinate of each element modeled.
This enabled close cooperation between the BIM modeler and the surveyor, who was responsible for tracking the installation points of the elements, such as tunnel-face stabilization bolts and umbrella pipes.
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