Seismic performance evaluation of assembled O-Stable Panel walls

O-Stable Panel is a new type of assembled structural wall. Three integral prefabricated panel specimens with different vertical connections at the bottom and one full cast-in-place panel specimen were designed and tested under low cycle lateral reciprocating loading to evaluate the seismic performance properties of the O-Stable Panel system, such as bearing capacity, ductility and hysteretic energy dissipation. The performance of the prefabricated O-Stable Panel systems was compared with that of the full cast-in-place panel. The scale of the specimens is 1:2 to the prototype structure, and the steel reinforcements of the panels were designed based on the detailing for the full cast-in-place RC structure in accordance with the current Chinese seismic design code. It is revealed that under the lateral reciprocating loading, vertical cracks were developed for all prefabricated O-stable panel specimens, penetrating the thickness of the panels at the panel joint and at the positions where panel thickness variation occurs at the ultimate failure state. The O-stable panels are found to exhibit symmetric and stable hysteretic curves without obvious pinching shape of the curves. The panel using grouting sleeve in vertical joint for steel rebar exhibits sharp degrading in seismic index when the lateral drift of the wall increases. For the panels with the preinstalled rebar stretched into the foundation beams for the vertical rebar joint, the equivalent damping ratio of the walls is greater than that of a full cast-in-place panel, and the value of their hysteretic energy dissipation is very close to that in a full cast-in-place panel.