**5. Case Study of the Nanterre 2 CESI Project**

This first case study extends the 4D BIM literature by presenting empirical evidence on the implementation and use of 4D BIM tools during the construction phase of an educational building. The Nanterre 2 CESI project (Figure 6) is a four-storey building intended to increase the teaching capacity of the CESI campus in Nanterre. There were two reasons for adopting BIM for the design and delivery of the project. Firstly, so that the deliverables produced by the project participants could be saved at each phase in order to make them available to CESI teaching teams and serve as real case studies. Secondly, so that the information contained in the deliverables allowed CESI to manage the operation and maintenance of the building using BIM-based workflows.

**Figure 6.** Location of Nanterre 2 (new) and Nanterre 1 (existing) buildings on Rue Kléber.

#### *5.1. Nanterre 2 CESI Project*

The Nanterre 2 CESI project is composed of: (i) a ground floor of 800 m2: coworking and catering space; (ii) the first floor to the third floor (800 m2 per floor): teaching spaces; (iii) the fourth floor (600 m2): Living Lab. (i.e., BIM modelling, RA/RV, and digital simulation spaces); (iv) parking for employees, professors and/or researchers, and green spaces. Construction works were planned for a 12-month period (between 5th May 2018, and 31st May 2019). CESI, as client, specified the use of BIM for the design and construction of the Nanterre 2 building. Apart from its intrinsic commitment to the use of the latest available technologies, CESI also wanted to use the project as a case study that provided data for teaching and research programmes in digital construction. Therefore, in commissioning the Nanterre 2 building, the client, CESI, followed a similar process to that

described in (the later published) ISO 19650: 2 [81]. This involves the 'appointing party' specifying, as part of its tender documents, a set of 'exchange information requirements' (EIRs) which prospective appointees then reflect in their tenders, and which form the basis (subject to pre-contract negotiation) of the appointed delivery team's BEP. In this case, a BIM specification document (equivalent to a set of EIRs [81]) was produced that included 10 BIM use cases. These were:


Ultimately, however, for the works to proceed, it was agreed that the appointed delivery team could omit several (marked as \*, above) of the BIM use cases. The main reasons for this were the deficiency of certain aspects of the requirement specifications as well as the diversity in the level of BIM expertise and maturity within the delivery team. One such omission was the requirement to provide 4D BIM. For this use case in particular, the BIM specification document only stated that a 4D software must be mastered, indicating Navisworks as an example. The mistake made was to only cite the type of software without specifying its capabilities. In this case, Navisworks was not capable of managing the construction site and monitoring, in real time, construction work progress. These were precisely the two uses of 4D BIM expected by CESI. The second shortcoming was due to the procedure described. It was simply indicated that a 3D model and a schedule must be linked to enable the extraction of a video animation and the phasing logbook (in French the carnet de phasage). This procedure was based on the Hardin and McCool method [96]. It was not indicated which 4D parameters should be produced, by whom, and how to ensure overall planning consistency. This being the case, and believing that it had sufficient in-house expertise, CESI decided to implement the 4D BIM planning of Nanterre 2 internally with the help of academic research teams that were familiar with digital construction. Their experience in doing so is the basis of the developmental case study reported here.
