祁连山区大坂山隧道围岩的冻融状况分析  

Analysis of Freeze-Thaw Condition in the Surrounding Rock Wall of the Dabanshan Tunnel in the Qilian Mountains

作　　者：何春雄[1] 吴紫汪[2] 朱林楠 

机构地区：[1]华南理工大学应用数学系,广东广州510640 [2]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《冰川冻土》2000年第2期113-120,共8页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金资助项目!( 4 96710 2 0 )

摘　　要：通过对严寒地区隧道现场基本气象条件的分析 ,建立了隧道内空气与围岩对流换热及固体导热的综合模型 ;在隧道内空气以紊流为主的情况下 ,分析预报了祁连山区大坂山隧道开通运营后洞内温度及围岩冻结、融化状况 ,并与在隧道内空气以层流为主的情况下的已有结论进行了比较 .Based on the analyses of fundamental meteorological and hydrogeological conditions at the site of the Dabanshan Tunnel in the Qilian Mountains, a combined convection-conduction model was constructed for turbulent air flow in the tunnel and temperature field in the surrounding rock. Then, with the in situ conditions of air temperature, atmosphere pressure, wind force, as well as the hydro-thermal conditions, the relationship between the temperature on the surface of the tunnel wall and the air temperature at the entry and exit of the tunnel has been obtained, the freeze-thaw conditions in the surrounding rock wall of the tunnel is predicted, and the simulated result is compared with that obtained in the case of laminar air flow in the tunnel. Many tunnels, constructed in the cold regions of the Tibetan Plateau, are at an elevation above 4 000 m and nearby the ridge of mountain. Since there is cold air flowing in the cold regions almost all the time and there is no wind protective screen, the wind-velocity in situ of the tunnels is more than 5 m/s, and because of the difference of atmospheric pressure, air temperature between the entry and exit of the tunnel, the air flow in the tunnel would be turbulent. In order to deal with the complex random unsteady nature of the turbulent air flow, the Reynolds time-average equations were used, that is, based on the classical Navier-Stokes equations, introduced the pulsate kinetic energy equation (K-equation) and dissipativity equation (ε-equation), then, by the Boussinesq assumption, the algebraic relationship of the turbulent kinematic viscosity v t , pulsate kinetic energy K and dissipativity ε are obtained. Combining these equations about the turbulent air flow in tunnel with the convective and conductive equations about the air temperature in the tunnel and about the temperature field with phase-change in surrounding rock wall, the whole mathematical model with a system of equations was constructed. In order to predict the freeze-thaw conditions for the Dab

关 键 词：祁连山区 隧道 围岩 冻融状况 

分 类 号：P642.14[天文地球—工程地质学] U455.5[天文地球—地质矿产勘探]