Shaking-table tests of a full-scale ten-story reinforced-concrete building (FY2015). Phase I: Free-standing system with base sliding and uplifting

•Seismic loads can be reduced by permitting sliding and uplifting of the base.•Tests of a full-scale 10-story RC structure were conducted to confirm the effect.•Specimen building was not moved sideways during small seismic exciton.•Specimen building was moved sideways during moderate and large seismic exciton.•The sliding and uplift behavior led to small maximum inter-story drift ratios. In this paper, results are presented from shaking-table tests of a full-scale 10-story reinforced-concrete structure to confirm the behavior of a free-standing system with a base that permits both sliding and uplifting. The purpose of this system is to use the seismic resistance of the structure during a small or medium earthquake and a sliding and uplifting behavior of the free-standing system during a large earthquake. Cast-iron plates were installed on the grade beams of the lower part of the specimen building to generate a low friction coefficient. Thus, the specimen building should be able to move sideways during large earthquakes, although the specimen building should not move sideways during small earthquakes. In the tests, the specimen building was moved sideways during tests with JMA-Kobe 25%, 50%, and 100% amplitude excitations but not during that with JMA-Kobe 10% amplitude excitation, and the specimen building was uplifted at one of its corners for all amplitude excitations. The base sliding displacement was 84–189 mm, and the corner uplift was 5–40 mm. The sliding and uplift behavior led to small maximum inter-story drift ratios, and these behaviors did not increase the base overturning moments. Thus, allowing sliding and uplifting behavior can reduce building damage in an extremely large earthquake.