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

4. SEISMIC RESPONSE OF PARTIAL-STRENGTH COMPOSITE JOINTS
inc-b
tr500-a
tr125-a
inc-c
tr125-c
inc-a
inc-e
tr500-b
tr500-c
tr125-b
tr125-d
inc-d
Figure 4.55. Interior beam-to-column joint measurement
equipment
4.10.2 Results of the PsD test n° 1
The behaviour of the structure was essentially elastic and no damage could be
observed at the beam-to-column joints and at the base joints. Only at the bottom
storey some little cracks were present on the slab in the joint areas, all parallel to
the transverse beams and starting from the edges of the steel sections of the
columns. Due to the presence of the concrete blocks at the second level, cracking
developed in the transverse direction, mainly on the column line. At the first step of
the Spatial Model procedure the frequencies of the first and second mode have
values equal to 2.31 Hz and to 7.81 Hz, respectively. The mean value of the modal
damping is very low, equal to 1.03% for the first mode and to 0.69% for the second
one. The maximum interstorey drifts reached at the first and second level are –9.7
mm and –12.3 mm, respectively. These correspond to a value of about 0.35% of
the interstorey height.
4.10.3 Results of the PsD test n° 2
The objective of the second test was to induce into the structure a first yielding with
no excessive damage. From a first visual inspection it could be observed that:
• no damage occurred at the column base, no crashing or spalling of the
concrete and no local buckling in the steel flanges;
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