Structural behaviour of stainless steel double extended end-plate beam-to-column joints under monotonic loading

• Published in: Thin-walled structures Vol. 151; p. 106743
• Main Authors: Gao, J.D., Yuan, H.X., Du, X.X., Hu, X.B., Theofanous, M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2020
• Subjects: Beam-to-column joint; Design methods; Experimental test; Extended end-plate connection; FE modelling; Stainless steel; Structural behaviour; Experimental test; Design methods; Beam-to-column joint; Stainless steel; FE modelling; Extended end-plate connection; Structural behaviour
• ISSN: 0263-8231; 1879-3223
• DOI: 10.1016/j.tws.2020.106743

The structural behaviour of beam-to-column joints with double extended end-plate connections is experimentally and numerically investigated in this paper. Two stainless steel grades representing austenitic and duplex stainless steel (i.e. EN 1.4301 and EN 1.4462 respectively) have been considered, whilst a joint made of the carbon steel grade Q345B was also tested as a benchmark to enable direct comparison of carbon and stainless steel joints. The employed bolt grades were A4-80 stainless steel bolts and 10.9 high strength bolts. A total of six full-scale joint specimens were tested including five stainless steel joints and one carbon steel control specimen and the applied force versus displacement (F-Δ) curves, as well as the corresponding moment versus rotation (M-ϕ) curves, were recorded and are reported herein, demonstrating excellent ductility behaviour of stainless steel joints. Advanced finite element (FE) models were developed using the ABAQUS software package and validated against the obtained test results, in terms of the obtained F-Δ curves and failure modes. The obtained initial rotational stiffness, plastic moment resistance and rotation capacity of the tested joints, were used to assess the accuracy of the predictions of the relevant European. American and Chinese design codes – EN 1993-1-8, ANSI/AISC 358-16 and GB 51022-2015 respectively – all of which are based on the respective design equations developed for carbon steel joints. It is concluded that the existing design standards lead to overly conservative strength predictions for stainless steel joints, as they fail to account for the significant strain-hardening and ductility of the material. Hence the development of novel design guidance in line with the observed response is warranted. •Six full scale tests on beam-to-column joints with double extended end-plate connections.•Stainless steel joints exhibited much more favourable ductility than their carbon steel counterpart.•Advanced finite element models were developed and validated against obtained test results.•Assessment of predictions from the relevant European, American and Chinese design codes.•Rotation capacities of tested stainless steel joints far beyond the limitations in current seismic codes.