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

4. SEISMIC RESPONSE OF PARTIAL-STRENGTH COMPOSITE JOINTS
For sagging bending moment, as depicted in Figure 4.40, the localization of the
stresses in the front of the column flange is evident. Moreover, under hogging
bending moment, the model clearly shows the distribution of the stresses in the
slab, due to the transfer of forces from the reinforcing bars in tension to the partially
encased column. Such distribution explicates well the cracks in the concrete slab
observed during the test, as depicted in Figure 4.41.
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(a) (b)
Figure 4.41. (a) Numerical distribution of the principal stresses of compression in the slab
under hogging bending moment; (b) cracks in the concrete slab due to the transfer of force
from the concrete slab to the column during the experimental test
Moreover, the model captures very well the deformed configuration of the joint,
with localization of plastic hinges in the flanges of the steel column, in
correspondence of the stiffeners and the yielding of the end plate in tension, as
depicted in Figure 4.42. Moreover, the stress concentration due to the mobilization
of the column web panel in shear is evident in the panel zone.
Figure 4.42. Plastic hinges in the flanges of the
steel column and yielding of the end plate in
tension