Finite element simulation of new RHS column-to-I beam connections for avoiding tensile fracture

• RHS column-to-I beam connections sustain brittle fracture during a large earthquake.
• Some improved ways can avoid the premature occurrence of brittle fracture.
• Tests in general can provide reliable results.
• However, tests that involve high costs, in some cases, are not feasible.
• The main objective of this work is to validate the FEM.

Many beam-to-column connections, consisting of rectangular hollow section (RHS) columns and wide flange I-beam connections, sustain brittle fracture of welded connections at the beam ends during a large earthquake. These fractures most frequently occur in regions around the beam bottom flange groove welds. A series of tests was conducted on an improved RHS column-to-I beam connection. The aim of the tests was to find possible solutions for avoiding premature occurrences of brittle fracture in RHS column-to-I beam connections. Research results show that the improved connection does not fail by fracture as observed in the conventional connections and has a larger energy dissipation capacity than the conventional types. This paper describes the finite element modeling method employed to analyze the new RHS column-to-I beam connection. The ABAQUS finite element package is used to simulate the experimental behavior, and three highly detailed 3D finite element models are created. These are complex models accounting for material nonlinearity, large deformation and contact behavior. The connection models have been analyzed through the elastic and plastic ranges up to failure. Comparisons with experimental data show that the models have high levels of accuracy.