特高海拔寒区隧道温度场分布规律研究

Study on Distribution Rule of Temperature Field in Tunnel in Extremely High Altitude Cold Area

为解决高寒高海拔地区运营隧道的冻害问题,在某单洞双向隧道4个断面的不同位置处布设了大量温度传感器进行现场温度监测,分析研究了特高海拔寒区隧道围岩、衬砌在不同位置处的温度场分布规律以及围岩冻深情况。结果表明:隧道温度随季节呈周期性变化,距洞口10 m处冻害最为严重;隧道衬砌温度与隧道纵向深度呈负相关,围岩温度与隧道径向深度呈正相关关系;在距隧道洞口越近的最不利断面处,拱顶温度高于拱腰和拱脚;距洞口10 m的拱脚处冻深最大,隧道冻深影响范围为0 m~250 m。研究结果可为寒区隧道施工和保温防冻提供依据和指导。

In order to solve the problem of tunnel freezing in high-cold and high-altitude areas,a large number of temperature sensors were deployed at different locations in four sections of a tunnel.Based on-site monitoring,the temperature field distribution and freezing depth of surrounding rock and lining and different locations of tunnels in extremely high altitude cold areas are studied.The results show that:1)The tunnel temperature changes periodically with the season,and the frost damage is the most serious at 10 m of the entrance;2)The tunnel lining temperature is negatively correlated with the longitudinal depth of the tunnel,and the peripheral rock temperature is positively correlated with the radial depth of the tunnel;3)In the most unfavorable section of the tunnel,the temperature of the vault is higher than that of the waist and foot of the arch;4)The freezing depth is the largest in the arch foot at 10 m of the entrance,and the affecting range of freezing depth of the tunnel is 0-250 m.The results of the study can provide a basis and guidance for the construction of tunnels in the cold area and the thermal insulation against freezing.