Shaking table test on a traditional pavilion-style wooden pagoda

Aiming at the seismic performance of traditional multi-story pavilion-style wooden pagodas, a shaking table test was conducted on a one-fifth scaled model of a seven-story pavilion-style wooden pagoda designed in Tang Dynasty style. Artificial and natural earthquakes with the seismic intensity levels ranging from frequent 7 degree to rare 8 degree as specified in the Chinese code were considered. The model acceleration and displacement responses and the inter-story shear force distributions were identified. Modal analysis and system identification theories were applied to quantify the dynamic properties of the structure. The test results indicate that the modal damping ratios of the first mode are more than 10%; the acceleration amplification coefficients are ranged between 0.5 and 1.0; the maximum inter-story drift ratio is observed in the beam-column frames, which is 1/52 under the seismic intensity of 7 degree, and the natural frequencies do not change noticeably. Comparatively, the maximum inter-story drifts are found to be 1/24 and 4/91 under the seismic intensities of rare 7 degree and 8 degree, respectively; the natural frequencies are decreased by up to 17% after the rare 8 degree earthquake inputs. However, the scaled model remained structurally sound after all the earthquake inputs with only mild cracking observed from the Ludous (cap blocks on top of the columns) and the Sandous (distributed blocks of the dou-gong joints), and slight pulling-out deformation from the mortise-tenon beam-to-column joints, implying a good seismic resistance of such timber pagodas. © 2017, Editorial Office of Journal of Building Structures. All right reserved.