Steel Buildings in Europe

Part 2: Concept Design 2 - 19 3.3 Luxembourg Chamber of Commerce Figure 3.5 Luxembourg Chamber of Commerce The headquarters of the cham ber of commerce of the Grand Duchy of Luxemburg was designed by Vasc oni Architects and comprises an existing building and 20000 m 2 of new office space as shown in Figure 3.5. A conference centre of approxim ately 8000 m 2 was provided together with 650 underground parkin g spaces on four levels. The total building area is 52000 m 2 including car parking. The four- and five- storey com posite st ructure consists of hot rolled steel sections and concrete floor slabs with inte grated IFB sec tions ( a ro lled asymmetric section with a wide bottom flange). The integrated steel beams are stiffened by the use of a lightweight truss below the beams, leading to a 40% increas e in span. S ervices are passed below the beams and through the truss to minimise the floor depth. The structure was assessed by a fire e ngineering analysis, which demonstrated that 60 minutes fire resistan ce co uld be achieved without additional fire protection. The IFB beam s are par tially p rotected by the concrete slab and support the reduced load in fire despite the loss of the exposed truss.