Ma et al. 2010
The paper builds on previous work provided by Eatherton et al. (2010). The presented research outlines the planning, design and preliminary results of a two-thirds scale rocking braced frame tested on the E-Defense facility in Japan.
System Concept
The structural system is composed of steel braced frames, vertical post-tensioning strands, and replaceable fuses. The frame is able to rock on its base while the seismic energy is dissipated through yielding of the fuses at the base. The frame remains elastic during the motion and the PT strands provide the uplift control and restoring force.
To further the work of Eatherton et al. (2010), large-scale shaking test were conducted at the E-Defense facility in Miki, Japan.
Experimental Study, Results and Discussion
The controlled rocking frame system was constructed at 2/3 scale. A reusable test bed assembly was used to provide inertial mass and bracing for out-of-plane stability. Three types of fuses were examined: non-degrading butterfly fuse, degrading butterfly fuse, and buckling-restrained brace. The tests were conducted using a scaled acceleration of the JMA Kobe NS and Northbridge Canoga Park ground motions.
Several conclusions were drawn from the experiment. The systems design criteria and constructability was exhibited. Parameters including self-centering, column base rocking and energy dissipation were validated. Also a less complex FEM model provided relatively accurate behavior predictions.
Reference
Ma, X., Deierlein, G. G., Eatherton, M., Krawinkler, H., Hajjar, J. F., Takeuchi, T., Kasai, K., Midorikawa, M., and Hikino, T. (2010). “Large-Scale Shaking Table Test of Steel Braced Frame with Controlled Rocking and Energy-Dissipating Fuses,” Proceedings of the 9th National Conference on Earthquake Engineering, Toronto, Canada, July 12-14.