Identification of vibration properties of a midrise wooden building using subspace identification method

Recent years, the mid-and high-rise wooden building using cross-laminated timber (CLT) is on the increase in the world. In the regions highly subjected to seismic events, it is important to know the basic property of the vibration of the building to design the building to be safety enough against the seismic load; however, there is enough such data of full scale wooden buildings. In this paper, the natural period, the damping ratio, and the mode shape of a full-scale five-story wooden building are evaluated using subspace identification method. The results show that the damping ratios of higher modes tend to be lower than that of the first mode, and the natural period and the damping ratio show amplitude dependency even in the range of low amplitude.