Seismic Stability Analysis for Caves with Gable Ceiling in Mogao Grottoes under the Vertical Earthquake Load

摘要

Gable ceiling was constructed in some of the caves in Mogao Grottoes.This design enriches the internal spatial structure of a grotto and is the integration of Chinese traditional and Buddhist grotto construction.The design is so unique and the rock mechanics hidden behind is so enormous that there are rays of wisdom of ancient Chinese on grotto engineering shining from the ceiling.There are still many questions on the design to be solved.The authors have chosen cave 254 of the Mogao Grottoes,which has a typical gable ceiling,for seismic stability analysis.3D computational model for the cave was constructed and vertical earthquake load was used in the analysis.Using input of various earthquake acceleration time intervals,rock stress has been analysed in four different simulation models.The result highlights critical positions for grottoes reinforcement,and provides scientific evidence for conservation and reinforcement engineering for protection of the grottoes from earthquake damage.