Design of stainless steel gapped K-joints in cold-formed square hollow sections

Current research on the stainless steel structures mainly focus on material and member behaviors, rare on the design on joints. This study carried out tests and theoretical studies on stainless steel gapped K-joints in cold-formed square hollow sections (SHS). Six gapped K-joints were tested. Material properties, joint capacities and failure modes were reported in detail. Then, a yield line failure mechanism considering both the de-formations of chord connecting face and chord sidewall was proposed, and the preliminary equation for joint capacity was derived. Afterwards, finite element models were developed and validated using the test data. Totally 560 finite element models were built and analyzed to calibrate the derived equation for the overall discrepancy, the effects of weld, and the yield strength of chord. Finally, test data on stainless steel gapped K-joint in SHS were collected in literature, and compared with the predictions of the design method in the CIDECT design guide and the proposed method. Results indicate that the proposed method has a better accuracy.