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

4. SEISMIC RESPONSE OF PARTIAL-STRENGTH COMPOSITE JOINTS
· the maximum rotation and local damage in the joints;
· the local damage in the columns;
· the value of the ratio between the input energy and the total hysteretic
energy dissipated.
After the elaboration of the numerical analyses, the accelerogram A-14 was
chosen because of the highest level of damage induced in the joints and the lower
values of damage in the columns. This last parameter was taken into account in
order to avoid dangerous global collapse due to the loss of stability at the base
level. The main characteristics of the accelerogram A-14 are reported in Figure
4.50.
a [m/sec 2 ]
spost. [m]
5.00
4.00
3.00
2.00
1.00
0.00
0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00
-1.00
-2.00
-3.00
-4.00
-5.00
0.15
0.10
0.05
time [sec]
0.00
0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00
-0.05
-0.10
-0.15
Sa [m/sec 2 ]
12.00
10.00
8.00
6.00
4.00
2.00
0.00
0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00
(a) (b)
time [sec]
vel. [m/sec]
0.40
0.30
0.20
0.10
-0.10
-0.20
-0.30
-0.40
T [sec]
0.00
0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00
time [sec]
(c) (d)
Figure 4.50. (a) Accelerogram A-14 employed for the analyses; (b) Elastic response
spectrum of the accelerogram A-14 with ξ equal to 5%; (c) Integrated base
displacements after the application of the baseline correction; (d) Integrated base
velocity after the application of the baseline correction
Main results
The pushover and the incremental dynamic analysis was performed and then
compared. Hereinafter the main results are reported in Table 4.7, whereas the
obtained response curves are plotted in Figure 4.51. The uniform and triangular
curves of the pushover analysis represent the upper and lower limit of the
response curve obtained by the IDA (Antoniou et al, 2002). Moreover, in our case,
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