： 高岩温会降低隧道衬砌结构的稳定性并恶化施工环境，在隧道结构中设置隔热层是一种较为有效的应对措施。为分析隔热层对衬砌温度的影响，基于隧道径向及轴向二维轴对称的围岩温度导热模型，引入第三类边界条件和莱维级数法推导得到隧道围岩温度分布的分析解，计算结果与已发表文献数据一致。以高黎贡山越岭段铁路隧道为工程背景，分析影响衬砌内外表面温度的主要因素。研究结果表明： 1）利用分析解不仅能够方便地量化不同隔热层敷设方式对衬砌的降温效果，还能确定不同内表面对流换热系数条件下衬砌内外表面温度及其梯度与隔热层导热系数之间的连续变化关系，例如对流换热系数取0.25 W/（m2?℃）工况下，采用夹心式敷设方式时衬砌平均温度比贴壁式低了约1.6 ℃； 2）当对流换热系数较大时，隔热层导热系数减小对降低衬砌内外表面温度的作用减弱，表明洞内通风条件较好时选择热阻较小的隔热材料也能满足隔热要求。

High temperature of surrounding rock will reduce the stability of tunnel lining and worsen the construction environment. It is an effective measure to set up the thermal insulation layer in the tunnel structure. An analytical solution of the temperature distribution is derived by 〖ＪＰ２〗introducing the thirdboundary conditions and the Levy method based on the radial and axial symmetrical twodimensional thermal conduction model of the surrounding rock so as to analyze the influence of the heat insulation layer on the temperature of the lining, and the validation results are consistent with the data of published literatures. The main factors affecting the temperature of the inner and outer surfaces of the lining are analyzed by taking the Gaoligongshan mountaincrossing railway tunnel as an example. The results indicate that: (1) The cooling effect of the different laying methods of the thermal insulation layer on the lining can be easily quantified by using the analytical solution; the relationships between the temperature and temperature gradient of inner and outer surfaces of the lining and the thermal conductivity of the thermal insulation under different convective heat transfer coefficients in the tunnel can also be determined, for example, when the convective heat transfer coefficient is 0.25 W/（m2?℃）,〖ＪＰ〗 the average temperature of the lining with the sandwich insulation layer is about 1.6 ℃ lower than that with the wallmounted insulation layer. (2) When the convective heat transfer coefficient in the tunnel is large, the effect of the thermal conductivity reduction of the insulation layer on the temperature decrease of the inner and outer surfaces of the lining is weakened, which shows that the insulation material with small thermal resistance can also meet the requirements of the insulation when the ventilation condition in the tunnel is good.