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

3. SEISMIC BEHAVIOUR OF BOLTED END PLATE BEAM-TO-COLUMN STEEL JOINTS
is associated with the coupling of two ‘thin’ elements with relatively heavy bolts,
showed the best performance in terms of mean energy ratio. On the other hand,
the coupling of a thick Tee stub with a column flange of similar thickness like the
C1B2-3 specimen ensues the lowest energy ratio.
3.5.3 Complete Joints
On the basis of the results of the coupled Tee stub tests, attention is focused on
joints JA1-2 and JB1-3, which appear to be more adequate in terms of seismic
design requirements. In this subsection the monotonic tests will be discussed as
well as the cyclic tests adopting the ECCS displacement procedure (1986). The
subsequent set of tests adopting the different procedures shown in Figure 3.4
aimed at providing data for the calibration of damage models considered but will
not be discussed in this study. Both the monotonic and the cyclic moment rotation
response relative to the Complete Joint endowed with a 12 mm end plate thickness
coupled with the column of HEA180 profile, i.e. JB1-2M and JB1-2A specimen,
respectively are illustrated in Figure 3.15.
REACTION MOMENT (kNm)
120
90
60
30
0
-30
-60
-90
JA1-2A
JA1-2M
-120
-75 -50 -25 0 25 50 75 100 125
ROTATION (mrad)
Figure 3.15. Experimental response of JA1-2M and
JA1-2A Complete Joints
Similar behavioural features were observed for the joint JB1-3A, and for the twin
specimens JA1-2B and JB1-3B (see Figure 3.16). These joints exhibited failure at
weld toes in the end plate part outside the beam section owing to fragile crack
propagation, as illustrated in Figure 3.17. This indicates a satisfactory behaviour of
the fillet welds. The monotonic response is characterized by inelastic phenomena
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