保温层对寒区隧洞衬砌结构温度的影响

EFFECT OF INSULATION LAYER ON THE TEMPERATURE OF TUNNEL LINING STRUCTURE IN COLD AREA

保温层是寒区隧洞安全运行的关键,保温层的设计对寒区水工隧洞至关重要。为分析保温层对隧洞衬砌结构温度的影响及保温效果,以新疆某引水隧洞为依托,基于现场温度监测数据,考虑对流-导热耦合作用的影响,采用有限元数值模拟方法,研究不同厚度、不同位置的保温层对隧洞衬砌结构温度变化的影响。研究结果表明,随着保温层厚度的增大,隧洞衬砌结构的温度变化逐渐趋于平缓。当保温层敷设厚度为0.06m及以上时,隧洞一衬、二衬温差最小,一衬、二衬温差与保温层的厚度呈负相关。从保温效果来看,表面铺设法与夹层铺设法相比,表面铺设法防冻害效果优于夹层铺设法。

Insulation layer is the key to the safe operation of tunnel in cold area,and the design of insulation layer is very important for hydraulic tunnel in cold area.Based on the field temperature monitoring data of a diversion tunnel in Xinjiang,the influence of convection-thermal coupling is considered and the finite element numerical simulation method is used to study the influence of insulation layer with different thickness and different position on the temper⁃ature change of the tunnel lining structure.The results show that the temperature change of lining structure tends to be gradual with the increase of insulation layer thickness.When the insulation layer is 0.06m and above,the temper⁃ature difference between the first liner and the second liner is the smallest,and the temperature difference between the first liner and the second liner is negatively correlated with the thickness of the insulation layer.Compared with the sandwich laying method,the surface laying method is better than the sandwich laying method in preventing freez⁃ing damage.