Seismic behaviour of high‐strength steel bolted extended end‐plate connections

Cyclic loading tests on 690MPa high‐strength steel bolted extended end‐plate connections were conducted to quantify their plastic resistance and plastic rotational capacity under seismic loading conditions. It was found that current formulae in Eurocode 3 Part 1‐8 still arrived at good predictions on plastic resistance of those connections. It was demonstrated that given the bolt grade and diameter, the end plate with an intermediate thickness led to the largest plastic rotation. Such an intermediate, or optimal, end‐plate thickness indicates that the upper limit of the end‐plate thickness, which is now specified in Eurocode 3 Part 1‐8 to ensure a sufficient rotation capacity, should be levered up by about 40% for 690MPa high‐strength steels in seismic design. In such a manner, the maximum plastic rotation of the high‐strength steel end plate was around 0.02rad. In addition, the high‐strength steel shear panel was able to develop a plastic rotation of at least 0.035rad, thus qualified as high‐ductility class (DCH) in Eurocode 8. The weak shear panel contributed for more than 70% of the total plastic rotation capability.