A New Concept in Joining Diagonal Bracings to Horizontal Ones

A new ‘universal’ structural joint with multiple applications was devised. Its application as a ‘beam-to-column joint’ was already investigated experimentally, and proven to be promising. The results were reported in previous OMAE conferences and elsewhere. Another fruitful application conceived for this joint is in the context of joining (diagonal) braces to the frame members of a structure. In particular, in chevron (inverted V) bracing systems, where the dominating exchanged forces between the combined diagonal braces and the horizontal brace (beam) are ‘shear,’ the use of the devised joint as a joining member can substantially improve the overall behaviour of the structure under dynamic loading, cyclic or else. This is due to the high ‘shear flexibility’ of this joint, emanating from 1) its high ‘shear deformation capacity,’ and 2) the ‘restored ductility’ of its material, both substantiated through experimental studies. However, numerical push-over study of a typical one-storey frame proved the effectiveness of using such notion in chevron-braced frames in every respect—the flexibility of the frame increased substantially. The elastic stiffness and the elastic limit decreased to more reasonable values, which guarantee the stable, non-violent failure of the frame if subjected to overload. Moreover, since this joint works in a ‘sacrificial capacity’ and is in the form of a ‘self-contained’ separate entity, connected to the joined-diagonals and the horizontal braces through bolts, it can be ‘replaced,’ if it receives excess damage, leaving the non-replaceable elements, braces, intact. Finally, since it is capable of joining structural elements of different materials to each other, it is expected to have a potential for being used in every structure, offshore or onshore, prone to be subjected to dynamic, cyclic or else, in its service life.