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x-bracing vs. cross bracing
a friend of mine said that there is a difference between x-bracing and cross bracing. he said cross bracing can carry compression whereas x-bracing is purely tension. anyone heard this one?
i've never heard that particular set of definitions, we use both interchangably. he is right that you can design an x-braced system by either counting on the compression strut or ignoring it (in the case of a rod x-brace).
vmirat:
nope. there is no difference between x-bracing and cross bracing. but there is an important difference between cross bracing and bridging.
at what brace stiffness can you no longer ignore the compression brace? what about smaller tubes and angles? it would seem that without enough deflection allowed by the tension side the compression brace cannot buckle.
i would agree, a 'x' braced system will transfer loads via either compression or tensions whereas the cross bracing (single diagonal brace) replys on only compression therefore in the 'x' braced system a tension force is much easier to design as buckling lengths are not important.
kieran
try looking at the mast and tower codes, bs8100 in the uk, eia222-f i think in the us.
you will still need to check the buckling capacity between the 'support' points of the compression members.
on the original subject an old employeer of mine refered to the tension system as x or cross bracing and the compression version as a double warren. |
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