Numerical study on steel braces under reversed cyclic loads

Diagonals are typically assumed as dissipative elements in seismic-resistant steel braced structures. However there are still some uncertainties on the behaviour of steel braces subjected to reversed cyclic loadings. The paper deepens such key issue, focusing on the numerical simulation of the experimental tests conducted by Black et al. (1980) on single steel members. FEM analyses are performed by means of the software ABAQUS v6.13-1 on three struts having either H-shaped, or circular, or square hollow cross-sections. A refined model, calibrated by varying boundary conditions, cross sections and slenderness ratios is set up, allowing for a suitable approximation of the hysteretic behaviour in terms of strength, stiffness and ductility. It is a powerful tool for parametric analyses, necessary for acquiring the main aspects of the cyclic behaviour, thus leading to the definition of appropriate design criteria.