Steel Buildings in Europe

Part 2: Concept Design 2 - 14 2 CASE STUDIES ON SINGLE STOREY BUILDINGS The following case studies illustrate the use of steel in single storey buildings, such as show rooms, production facilities, supermarkets and similar buildings. 2.1 Manufacturing hall, Express Park, UK Figure 2.1 Portal frame during construction The portal frame shows in Figure 2.1 forms part of a new production facility for Homeseeker Homes, who manufacture portable homes for residential parks. The project comprises a 150 m long production hall, an adjacent office building and a separate materials storage building. The production hall is a duo-pitch portal frame with a 35 m clear span and a height of 9 m to the underside of the haunch. The production hall has to accommodate four overhead gantry cranes, each with a safe working load of 5 t. Two cranes may be used in tandem, and the forces arising from this loading case had to be carefully considered. The longitudinal surge from the cranes is accommodated by bracing in the elevations, which also provides longitudinal stability. There are no expansion joints in the production hall – the bracing was designed to resist any loads from thermal expansion. To control the lateral deflection at the level of the crane rail, the frames, at 6 m centres, are rather stiffer than an equivalent structure without cranes. The columns are 762 mm deep and the rafters 533 mm deep. The gable frames are portal frames instead of a braced gable frame constructed from columns and simply-supported rafters, to reduce the differential deflection between the end frame and the penultimate frame.