Bracing
What is a cross brace?
A cross brace is a pair of diagonals forming an X across a bay, bracing it in both directions at once.
Use this diagram+
Free to use on your own site, in training material or in a course handout, as long as the credit link stays on it. Paste this where you want the diagram to appear.
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<img src="https://scaffoldoptix.co.uk/glossary/cross-brace/diagram.svg" alt="cross brace — scaffold diagram from ScaffoldOptix" width="880" height="620" loading="lazy">
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<a href="https://scaffoldoptix.co.uk/glossary/cross-brace">What is a cross brace?</a> — diagram by
<a href="https://scaffoldoptix.co.uk">ScaffoldOptix</a>
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</figure>Two diagonals crossing means the bay is braced whichever way it tries to rack, rather than in one direction only. It is a common arrangement on towers and on system scaffolds, where a cross brace is often a single prefabricated component.
On tube and fitting, a cross brace is simply two tubes fixed with swivels. On system scaffold it is frequently a hinged member that drops onto rosettes at both ends.
The X is also why cross-braced bays are awkward to pass through. On a tower, that is the trade-off for stiffness.
What goes wrong on site
- One diagonal of an intended pair fitted and the other left off.
- Cross braces removed at ground level to create an access route without an alternative arrangement.
- Prefabricated braces used on a frame they were not made for.