Abstract: A rod comprises a plurality of elongate members joined together in an assembly, with each elongate member having a generally T-shape cross-section and being formed from fibre reinforced sheet material. Each member comprises two outwardly curved members formed with first leg sections contiguously disposed and connected to form the web of the T-shape, second leg sections extending at an angle to the first leg sections, and a planar cap member spanning and connected to the second leg sections to form the cap of the T-shape. The cap member has opposite ends which define abutment faces. Each curved member has a curved radius portion between the leg sections, with the curved radius portions and the planar cap defining a space therebetween which is filled with a filler material. The cap members are joined together so that said abutment faces of adjacent cap members are contiguous, thereby forming the assembly.