Testing, numerical modelling and design of S690 high strength steel channel-to connections

This paper describes experimental and numerical studies of S690 high strength steel channel-to-plate con-nections failing by net section fracture. Experiments were conducted on 27 S690 high strength steel channel-to-plate connection specimens, with each consisting of a channel section member bolted to two gusset plates by web or flange. The test ultimate loads, load-elongation curves, failure modes and strain distribution at critical cross-sections were fully reported and analysed. The influences of the number of bolt holes, longitudinal pitch, connection length and out-of-plane eccentricity on net section efficiency were discussed. The experimental programme was followed by a numerical modelling programme, where finite element models were firstly developed and validated against the test results and then used to conduct parametric studies to generate further numerical data. Based on the test and numerical data, the accuracy of the relevant design rules, as set out in the European code, American specification and Australian standard, was assessed. The assessment results revealed that the European code leads to overly conservative and scattered ultimate load predictions, while the American specification and Australian standard result in unsafe and scattered ultimate load predictions. Finally, a new design approach was proposed and shown to provide substantially improved ultimate load predictions for S690 high strength steel channel-to-plate connections over the design codes. The reliability of the new design approach was also demonstrated by means of statistical analyses.