Other functions of connections

Connections can influence structural behaviour.

Connections can even be used to control the structural behaviour. The figure below shows a connection for a leisure pool roof at Windsor. The four rectangular tubes (a) are working mainly as a set of ties, carrying equal loads. The overall system is fairly flexible, and parasitic bending moments could develop in the tubes because of the deflection of the roof. (See the glossary for an explanation of 'parasitic' bending moments). By introducing pin joints in the members it was possible to eliminate these bending moments and minimise the size of the tubes.

At movement joints, special connection details are used.

At movement joints in buildings, special connection details are needed. Movement joints may be used for several reasons, such as to allow for thermal expansion or relative vertical movements of structure supported on different foundations. These can be accommodated by providing sliding or rotational connections.

Connections can also be used for decoration.

Connections which are visible can have a significant impact on the overall appearance. In such cases the details require careful design, and the decorative effect may be the principal design generator.