The results of a cyclic test on a precast RC column connected to the foundation through a grouted sleeve joint are presented. The column, having square cross-section with side length 0.5 m, was 3.7m heigh. It was subjected to an axial compression of 1700 kN using two externally post-tensioned 47mm-diameter Dywidag bars. A transverse displacement time-history was applied to the column cross-section 2.8m far from the column-foundation joint using a worm screw jack with nominal loading capacity of 500 kN. The test was stopped after 19 displacement cycles, when the complete spalling of the concrete cover took place at the base-joint. Correspondingly, a 15% degradation of the base-joint resistance was attained and the drift reached 5.25%. At this deformation level, the dowel action involving the connection rebars was significant, leading to a maximum slip within the joint of about 7 mm. The ultimate curvature was about 10 times the yielding curvature. Then, a behaviour factor of about 3.7 was estimated for use in spectral response analyses based on the Italian Standard.
Prova di pressoflessione ciclica su un pilastro prefabbricato collegato al plinto tramite ferri di ripresa inghisati
TULLINI, Nerio;MINGHINI, Fabio
2012
Abstract
The results of a cyclic test on a precast RC column connected to the foundation through a grouted sleeve joint are presented. The column, having square cross-section with side length 0.5 m, was 3.7m heigh. It was subjected to an axial compression of 1700 kN using two externally post-tensioned 47mm-diameter Dywidag bars. A transverse displacement time-history was applied to the column cross-section 2.8m far from the column-foundation joint using a worm screw jack with nominal loading capacity of 500 kN. The test was stopped after 19 displacement cycles, when the complete spalling of the concrete cover took place at the base-joint. Correspondingly, a 15% degradation of the base-joint resistance was attained and the drift reached 5.25%. At this deformation level, the dowel action involving the connection rebars was significant, leading to a maximum slip within the joint of about 7 mm. The ultimate curvature was about 10 times the yielding curvature. Then, a behaviour factor of about 3.7 was estimated for use in spectral response analyses based on the Italian Standard.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
