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

4. SEISMIC RESPONSE OF PARTIAL-STRENGTH COMPOSITE JOINTS
damage has occurred. Basing on the numerical results taken out from IDA and
from the Pushover analysis, the value of PGA employed for the 20%
Earthquake was estimated at 0.25g.
3. The 100% earthquake PsD test was conducted by applying the input
earthquake. So as provided by EC8, the minimum capacity in terms of plastic
rotation of the beam-to-column joints is equal to 35 mrad. For the estimation of
the PGA at the Ultimate Limit State, this last parameter was so considered.
From IDA and Pushover analysis the value of acceleration equal to 1.4g was
taken out. As a result, a significant amount of damage is inflicted to the
structures. As a matter of fact, an artificial accelerogram will provide more large
inelastic cycles for observation, but may damage the structure too much before
the cyclic test.
4. For the Near to Collapse test, the values of PGA - equal to 1.8g - were
calculated.
5. A final cyclic test is conducted according to the ECCS 45 (1986) procedure to
study a severe amount of damage in the members and connections in a
controlled and systematic way, which is not possible by means of earthquake
PsD tests.
4.10.1 Testing apparatus and instrumentation
Four actuators are needed (two for each storey) together with the relevant exterior
digital transducers (see Figure 4.52 and Figure 4.53). For the measurement of the
rotation capacity of the joints and the deformation of the structural element
(composite beam, partially encased column and connection) inclinometers, strain
gages and LVDTs will be used.
3500
3500
Distributing frame
7000
Figure 4.52.Lateral view of the 3D frame
Hydraulic jacks Reaction wall
5000
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