Compressive strength and behaviour of gusset plate connections with single-sided splice members

Due to the ease of fabrication and construction, gusset plate connections with single-sided splice members are a popular connection type in building frames and light structures. However, this detail produces local out-of-plane eccentricity, which can be detrimental to the ultimate strength of the connections. This paper presents experimental, numerical, and analytical investigations of the compressive behaviour of eccentrically loaded gusset plate connections. Three full-scale tests were conducted, including two specimens with unstiffened splice members and the remaining one with stiffened splice members. The ultimate loads of the three specimens were found to be evidently less than the concentrically loaded specimen which has been earlier reported. Finite element (FE) models were then established, which were validated through comparisons against the test results. The sensitivity of the FE models to the initial imperfections was also studied. An extensive parametric study was subsequently performed, and the influences of varying gusset plate and splice member geometric configurations were discussed in detail. Three key failure modes were identified for the eccentrically loaded gusset plate connections, namely, Gusset-Splice Interactive Plastic Failure (G-SIPF), Splice Plastic Failure (SPF), and Gusset Plate Buckling (GPB). A set of design rules based on the nature of each failure mode was proposed accordingly, where good agreements were observed between the FE and the design results in terms of both the ultimate load and the governing failure mode. Worked examples were finally provided to clearly illustrate the proposed design procedure.