Experimental study on torsional vibration behavior of steel frame specimen with eccentricity

Torsional response can destructively effect the seismic capacity of structures. Many damaged buildings due to torsional vibration were observed after sever earthquakes. However, it cannot be said that the mechanism of the damage due to the torsional vibration had been clearly investigated. The main purpose of this paper is to reproduce the torsional response with the pseudo dynamic test technique. One-span, one-bay and two-story steel structures were tested. Three structures that had different eccentric ratios were designed for the pseudo dynamic tests. Furthermore, shaking table tests on three structures were conducted to verify the validity of the pseudo dynamic tests. From the shaking table and the pseudo dynamic tests, it was confirmed that the pseudo dynamic test can adequately reproduce the response of structure with eccentricity; eccentricity was not as effective on the maximum horizontal displacement at center of gravity, but the maximum rotational angle was increased according to its eccentricity.