Behaviour of duplex stainless steel bolted connections

Abstract

This study deals with the behaviour of duplex stainless steel bolted connections. The aim of the study is to respond to the question if the current stainless steel design specifications are able to predict the behaviour of such connections. Firstly, the net cross-section capacity of duplex stainless steel plates subjected to tensile loading are presented. They were conducted to obtain the stress–strain curves and tensile fracture behaviour used to support the finite element (FE) fracture simulations. Secondly, nonlinear FE models are developed for duplex stainless steel bolted connections subjected to tensile loading. The FE models are validated against experimental data in terms of load–displacement curves, failure modes and ultimate loads. Then, a numerical parametric study that consists of 133 duplex stainless steel grade EN 1.4162 bolted connection specimens is carried out. The failure modes of bolted connections are carefully examined, including combined tear out and bearing, bearing and net section, looking at the influence of parameters such as end distance, edge distance and spacing between the bolts in the connections. The results are compared to the design rules prescribed in the current stainless steel design specifications. Generally, it is found that the Australian/New Zealand (AS/NZS), American (SEI/ASCE) Specification and European codes conservatively predict the ultimate strengths of the bolted connections, whereas the strengths predicted by the AS/NZS and SEI/ASCE specifications are overall more accurate and less scattered.