Pleated    Structures

Softer boundaries

One of the virtues of using cables to support membranes is that it provides a more gentle means of support than using high points.

The number of points supported is increased - and the force required at each point is reduced.

The effect is similar to that produced by using curved arches (or bent poles) to push up the fabric - though of course using cables tends to be lighter and cheaper.

Even softer boundaries

This page addresses the question of whether the membrane support can be softened further somehow.

One way of doing this is to use the flat pattern.

Another method employs a thermal insulator around the cables - which increases their effective radius.

However, there's also something else that can be done:

Most pleated structures use a single valley cable - like so:

One cable

Looking at some of the structures that have been built, the possibilty of using more than one valley cables arises.

More than one valley cable

Attempting to cover more than a small distance like this is probably impractical - since the cables would tend to get pushed together at the bottoms of the valleys - unless they were held apart somehow.

However the cables being pushed together may not be the end of the world - even directly adjacent cables can help to distribute the curvature in the membrane surface over a larger area.

Two cables

Two cables is the most obvious possibility. Together these two cables create a more gentle curvature than is produced by a single cable.

Three cables

Assuming the pleats are not too deep, three cables may also be possible.

These multi-cable patterns have a price - there are more cables and fittings - which are likely to increase costs and assembly time.

However if they help avoid bruising, damaging and wear of the fabric membrane it might well be worth it.


The essay on blunt pleats is related to this one.

Tim Tyler | Contact |