Structure and architectureFig. 1.15 The high strength of steel allows the creation of
structures with very slender elements. In buildings which
are supported by steel frameworks the volume occupied by
the structure is low in relation to the total volume of the
building. (Photo: A. Macdonald).
Fig. 1.16 Multi-storey steel frameworks are typically a
combination of l-section beams and H-section columns.
(Photo: A. Macdonald).
on the site by pouring the concrete into
moulds.
The strongest of the structural materials is
steel, which is therefore used for the tallest
buildings and the longest spans. It is a highly
versatile material, however, and is also used
over a very wide variety of building types and
span sizes. Because it is very strong the struc-
tural elements are slender and of low volume,
so that steel is used almost exclusively in the
form of skeleton-frame structures (Fig. 1.15).
The majority of these are assembled from
standard rolled sections; these are elements
with I- and H-shaped cross-sections (Fig. 1.16)
and longitudinal profiles which are straight 13