Evaluation of Long-Term Stability of Mogao Grottoes Caves under Enhanced Loading Conditions of Tourists

AbstractAs one of the largest and best-preserved Buddhist art treasure houses in the world, the Mogao Grottoes attracts a great number of tourists from all over the world. With an increasing number of visitors, the influence of visitors on the stability of network caves will increase as well. To understand the influence of tourist static load on the caves and the long-term stability of the Mogao Grottoes, the stress distribution and deformation characteristics of surrounding rock mass are analyzed under different tourist static loads using a finite-difference method. The analysis shows that these will produce a stress concentration and large vertical displacement on the cave roof and densely distributed cave area. Meanwhile, tourist load has a slight but not significant influence on the changing of the stress distribution of the caves, and the influence on the displacement is relatively obvious; however, the influence can be neglected due to its small displacement. Consequently, the effect of tourist load on the stability of the caves is not significant. However, different distribution types of tourists within the caves have an obvious effect on the distribution of displacement. Distribution of tourists on both sides of the cave should be the recommended process, mainly because it can effectively reduce the vertical displacement of the roofs and floors of the caves. Moreover, the analyzed results are of great significance to tourist management as well as to the long-term preventive protection of the Mogao Grottoes.