Timber structures
placed in different directions so as to produce
a shell which has similar structural properties
in all directions. The shell is normally
supported on edge beams of laminated timber
which are integral with the shell itself. For ease
of construction and analysis shapes which
have a regular geometry are usually adopted.
The hyperbolic paraboloid (Fig. 6.59) is particu-
larly suitable but other forms, such as the
conoid and the elliptical paraboloid, have also
been used.
6.7.6 Lattice domes and vaults
In this form of construction triangulated
arrangements of timber elements are built up
into domed or vaulted shapes (Figs 6.60 to
6.62). The resulting structures are very
efficient due to the form-active or semi-form-
Fig. 6.62 The lamella vault is a system which allows
large interiors to be created. The degree of standardisation
which is present can make this an economical form of
construction.
active overall geometry and are therefore
suitable for large enclosures (span range
15 m to 200 m). In the lamella system each
element is twice the length of the side of a
diamond, and at each joint, one element
passes continuously through, with adjacent
intersecting elements connected to its mid-
point. Triangulation of the geometry is
effected with purlins. The particular advan-
tage of the lattice vault or dome is the high
degree of standardisation of the components
which is possible.
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