中文摘要：

研究敦煌莫高窟壁画的起甲机理,为壁画的起甲成因及其修复保护提供理论依据。通过ANSYS有限元建立温度场下壁画的内力作用模型,分析起甲壁画的临界受力状态。推断壁画温度场和应力场的产生及其分布规律,并观察壁画受热膨胀的结果。随着时间的变化,壁画与空气接触的表面的热量逐渐向内部均匀扩散,引起有一定厚度的壁画的温度梯度升高。壁画在温度场中受温差影响出现了明显的膨胀起甲现象,当起甲达到一定程度时,在外力作用下壁画就会出现脱落。

英文摘要：

The flaking mechanism of Mogao Grottoes murals at Dunhuang is studied to provide the theoretical foundation for flaking contributing factor of murals and its repair and conservation. The endogenetic action model of the murals under temperature field was established by ANSYS finite element analysis software to analyze the critical stress state of the flaking murals. The generation and distribution law of the murals temperature field and stress field are deduced,and the thermal expansion results of the murals are observed. As time goes on,the heat from the contact surface of the murals and air is evenly diffused to the internal layer of the murals gradually,which causes temperature increase with gradient of the murals with a certain thickness. The murals under the temperature field influenced by the temperature difference appears significant expansion and flaking phenomenon. When the flaking phenomenon reaches to a certain degree,the murals will fall off under exogenic action.