HAVAS CONSEIL OFFICES, NEUILIY, FRANCE

The building is held by six two-storey high steel box portal frames, these frames being supported by a separate concrete substructure with six basement floors below street level. Prestressed composite steel beams are used for the main building spans.

The glazed cylinder, placed asymmetrically, about one third down the length of the building, forms a counterpoint for the rest of the building and contains lifts, stairs and ducts for vertical distribution of services. It is constructed of one central steel tubular column 457 mm in diameter with twelve 300 mm diameter steel tubular columns around the periphery supporting ring and radial steel beams; these support the floor slab which consists of a 15 m diameter concrete. The columns are filled with concrete. The rest of the building is supported by six external portal frames which are heavily loaded. The portal frames consist of heavy box-section steel columns, 700 x 1200 mm in section, resting on 740 x 1 000 x 48 mm neoprene pads at street level, and a box-section transverse member of the same size overhanging the top of each column by 3.50 m. The two middle portal frames, in the larger of the two rectangular parts of the building, have heavy longitudinal beams rigidly connecting the tops of the columns together. In the storeys above this, there are rigid internal frames in the same plane as the main, street-level portals, to which they are welded; these frames are attached to each other by internal longitudinal beams. The longitudinal beams are prestressed composite steel beams with an overall depth of 650 mm. Parallel to them are the facade beams which have a 1200 mm deep I-section shape.

A 160mm concrete slab spans the 5.40 m between these longitudinal beams, resting on top of the internal beams and on shelf angles on the facade beams, the angles being welded to the inner face of the facade beams at mid-depth. Because of the number of portal frames, the longitudinal beams have to span large distances, up to a maximum of 23.40 m for the facade beams and 15.30 m for the internal beams.

The ground floor portals were shop fabricated in three parts and welded together on site at joints near the top of each column. The internal box-section columns were brought to site in sections either three or four storeys high and then site welded to beams, cross-bracing being used before the welding was complete.

Notes:

box portal frame портальная рама коробчатого сечения

counterpoint n. контрапункт

neoprene n. неопрен

ring beam кольцевая балка

shelf angle уголковый ригель фахверка

Ответьте на вопросы к тексту

1. What is the building held by?

2. What is the structure of the glazed cylinder?

3. What do the portal frames consist of?

4. What are the features of the two middle portal frames?

5. Why do the longitudinal beams have to span large distances?

6. What are the features of the ground floor portals?

7. What elements of the structure required welding?