ABSTRACT
In half-through U-frame footbridges, the behaviour of RHS chord members in transmitting out-of-plane moments between floor members and bracing members in the girder plane is a key factor in determining the buckling strength of the compression chord. Experimental and analytical research was carried out into the behaviour of tubular joints in such bridges. Unstiffened RHS chords are shown to be much more flexible than those stiffened by a plate inserted and welded in place across the diagonal at the connection. The consequences on global behaviour of the U-frame structure are examined.
