Analysis and modelling of the seismic behaviour of high ... - Ingegneria

3. SEISMIC BEHAVIOUR OF BOLTED END PLATE BEAM-TO-COLUMN STEEL JOINTS
• analysing the seismic performance of partial strength bolted extended end
plate joints with fillet welds, which represent an alternative to fully welded
connections for use in seismic force resisting moment frames;
• verifying in a low-cycle fatigue regime the feasibility of the mechanical
approach adopted for joints undergoing monotonic loading, whereby the
properties of a complete joint are understood and obtained by assembling
the properties of its component parts.
The study was limited to one basic connection geometry representative of a typical
European design, viz. bolted extended end plate connections with overmatching
fillet welds, as depicted in Figure 3.1. However, different design parameters,
among which the end plate thickness and the bolt diameter, were addressed. A
series of tests on connection substructures and subassemblages subjected both to
monotonic and cyclic displacement regime was carried out. These results allow the
component method to be appraised. Also mechanical and metallurgic
characterization test data of the connection material are collected.
Figure 3.1. Bolted extended end plate beam-to-column joint
On the basis of the experimental results and the data collection, inelastic finite
element (FE) analyses carried out by means of the ABAQUS code (Hibbitt,
Karlsson & Sorensen Inc., 2001), both on isolated Tee Stub (ITS) connections and
on Complete Joints (CJ) have been performed. Therefore, both FE models were
calibrated and the stress and strain state of the aforementioned connections was
simulated both in the monotonic and in the cyclic displacement regime. Finally,
some design parameters which influence the fracture resistance of steel bolted
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