Dynamic characteristics and seismic responses of painted sculptures of Dunhuang Mogao Grottoes

The painted sculpture of Dunhuang Mogao Grottoes is an important constituent of Dunhuang's cultural art. To study the painted sculpture's seismic safety, experimental specimens and numerical models were established on the basis of original geometry and internal constitutions. These specimens and models were made of wooden frame, reed-padded layer, coarse clay layer, and fine clay layer from internal to external. The dynamic characteristics of the painted sculptures were obtained by sweep frequency experiments. The numerical model can reflect dynamic performance of experimental specimens by comparing the results of sweep frequency experiment with numerical modal analysis. Based on the numerical results, the responses of the painted sculptures were analyzed from the perspectives of stress, displacement, and acceleration, evaluating the painted sculptures' responses to seismic activity at three levels expected for the Dunhuang area, and finding the regions of easily damaged. The results show that there is a risk of damage to painted sculptures, though the displacement responses are small under the earthquakes with PGA = 0.20 g.