Expression of bracing

Of the several methods used to achieve lateral stability in framed construction, diagonal bracing is the one which offers the clearest and most direct visual and graphic representation. For this reason, bracing has been used as an explicit form of structural expression. When brought to the exterior, bracing is often used to ornament the building as well as to serve a structural function. Bracing used for compositional effect can be more than the minimum necessary for structural purposes, as is the case in Figure 2.3.

Figure 2.4 shows a new visitor centre for a thirteenth-century castle, which was built over some of the archaeological relics. The structure had to be lightweight to reduce the size of the foundations, and the number of columns had to be limited to avoid interference with the exhibition space below. The inherently lightweight nature of the building is expressed by an external structure, with the diagonal bracing adding a further element of interest.

Often, the location and orientation of the bracing has to satisfy other criteria, such as the provision of large openings or the spatial alignment of the cladding elements. In this case, the range of architectural options for bracing systems is constrained by the building function.

In multi-storey buildings, bracing can be expressed externally to architectural effect. The structural importance of the bracing members means that their size and detailing must conform to sensible load paths by minimising eccentricities and points of weakness. Welded stiffeners are often required to transfer forces across highly stressed members.

Exposed Steel Structure
2.3 Reliance Controls, Swindon, with multiple braced panels (the stubs of the steel roof beams were left exposed to facilitate easy extensions to the factory) (architect: Foster and Partners)
Architecture Vertical
2.4 Visitor centre, Limerick, Ireland. The structure of the building is expressed on the outside, including the vertical bracing (architect: Murray O'Laoire Associates)

2.5 Internal arch structure over railway lines at Broadgate, London (architect: Skidmore Owings & Merrill)

Greener Homes for You

Greener Homes for You

Get All The Support And Guidance You Need To Be A Success At Living Green. This Book Is One Of The Most Valuable Resources In The World When It Comes To Great Tips on Buying, Designing and Building an Eco-friendly Home.

Get My Free Ebook


Post a comment