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The world largest three-dimensional earthquake simulator, E-Defense, has been operated and available for shake As a part of the project, seismic performance of reinforced concrete (RC) buildings were investigated through full-scale shake table tests at E-Defense in 2005 and 2006. The second phase tests were conducted for two three-story school buildings from September to November 2006. One was a bare RC specimen simulating an old and non-ductile school building with short columns, while the other was a retrofit specimen, which was constructed in the same design and strengthened with attached steel braces. The two specimens were constructed on the concrete flat slab base with construction joint simulating spread foundation, where sway and uplifting behavior would occur in seismic response of the shake table test. An obvious low level of input and damage to the building structures was verified experimentally, which was owing to the base slip behavior under an extreme earthquake motion. The plan, procedure and results of the full-scale shake table test on the first bare RC specimen are reported in this paper.

A full-scale shake table test on a six-story reinforced concrete wall frame structure was carried out at E-Defense, the world's largest three-dimensional earthquake simulation facility, in January 2006. Story collapse induced from shear failure of shear critical members (e.g., short columns and shear walls) was successfully produced in the test. Insights gained into the seismic behavior of a full-scale specimen subjected to severe earthquake loads are presented in this paper. To reproduce the collapse process of the specimen and evaluate the ability of analytical tools to predict post-peak behavior, numerical simulation was also conducted, modeling the seismic behavior of each member with different kinds of models, which differ primarily in their ability to simulate strength decay. Simulated results showed good agreement with the strength-degrading features observed in post-peak regions where shear failure of members and concentrated deformation occurred in the first story. The simulated results tended to underestimate observed values such as maximum base shear and maximum displacement. The effects of member model characteristics, torsional response, and earthquake load dimensions (i.e., three-dimensional effects) on the collapse process of the specimen were also investigated through comprehensive dynamic analyses, which highlighted the following seismic characteristics of the fullscale specimen: (i) a model that is incapable of simulating a specimen's strength deterioration is inadequate to simulate the post-peak behavior of the specimen; (ii) the torsional response generated from uniaxial eccentricity in the longitudinal direction was more significant in the elastic range than in the inelastic range; and (iii) three-dimensional earthquake loads (X-Y-Z axes) generated larger maximum displacement than any other loading cases such as two-dimensional (X-Y or Y-Z axes) or one-dimensional (Y axis only) excitation.

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