When complete in 2006, the Lex 2000 tower block close to the European Commission's Berlaymont building will be a prestigious home for European Parliamentarians and their staff.
But prestigious city centre locations usually come with much historical baggage attached, and Lex 2000 is no exception.
Its triangular plot is bounded on one side by a busy suburban rail line, on another by a low level road that conceals a culverted river. The third boundary is a high level highway, below which lurks a Metro tunnel. The design places Level 0, equivalent to the main ground floor, at the highway level, to bring it in alignment with the Berlaymont. Below this are five levels of basement car park, above a two storey entrance lobby topped by 12 floors of offices and conference facilities. To cope with the difficult ground conditions steel plunge columns had to be combined with both insitu and precast concrete in a top down construction sequence, which is still under way.
'Getting to Level 0 will take 15 months, ' says Waterman TCA managing director Jean Tisseghem.
'Once you get there you need to get the rest of the structure up as quickly as possible.'
This superstructure embodies most of the signature details that mark the 'Brussels school' of precast design. Circular columns with minimal corbels will be cast in self-compacting concrete of grade C90/105. Most will be two storeys high. Connection details in this high profile building will feature substantial continuity of reinforcement to minimise the risk of disproportionate collapse (see diagram). Beams and floors will be precast pretensioned prestressed factory produced units, with double tee units 18m long used over the conference areas and hollow core floors everywhere else.
Cores will be jump formed, floor to floor height is a tight 3.42m.
The main structure is programmed to take 11 months, equivalent to a floor every three weeks, with the completed building due to be handed over to its new tenants in 2006.