中文摘要：

风化作用是导致石窟围岩失稳的重要因素。通过数值模拟计算，研究了云冈石窟在风化作用下的岩体稳定性。选取云冈石窟中部5号窟-13号窟作为研究对象，对组成石窟的岩体进行了分类和质量评价，并据此确定数值计算的力学参数。通过数值计算，得到了石窟的应力分布，进而确定了岩体可能发生失稳的薄弱点。计算结果表明，云冈石窟各洞室岩体目前基本保持稳定，但随着时间的推移，风化作用会持续对岩体造成破坏，并导致岩体失稳。数值计算给出了石窟岩体失稳的位置和顺序，可为云冈石窟的治理与维护工作提供参考。

英文摘要：

Weathering is an important factor to cause cavern rock mass instability. Through numerical simulation, the stability of Yungang cavern~ rock mass under weathering action was studied herein. The central No. 5 - No. 13 Caves of the Yungang Cavern being selected as the study objects, the rock mass composing the cavern was classified and evaluated, and the mechanical parameters of the numerical calculation were determined. The stress distribution of the cavern was obtained by numerical calculation, and the weak points of the rock mass where instability may oc- cur were determined. The calculation results show that the rock masses of Yungang Cavern are basically stable now, but as the time goes on, weathering will continually destroy rock mass and cause its instability. The location and order of the cavern rock mass instability are given by the numerical calculations, which could provide a refer- ence to control and maintenance work of Yun~an~ Cavern.