新型管幕冻结法温度场数值分析
Numerical analysis of temperature field of new pipe-roof freezing method

运用有限元软件分析新型管幕冻结法温度场发展与分布规律,通过数值模型中的6条路径对冻土帷幕的发展、厚度变化和封闭性进行研究,结果表明:冻结8 d时圆形冻土帷幕开始交圈,30 d时管幕间冻土帷幕已经形成,为平均温度-18 ℃的0.6 m厚冻结壁,40 d时管幕间平均温度-18 ℃的冻土帷幕厚度达到0.8 m,且有透过管幕发展成连续冻结壁的趋势;冻结16 d时0 ℃以下冻土帷幕厚度已达1 m,-10 ℃以下冻土帷幕厚度达到1 m所需冻结时间为35 d;钢材与冻土界面上的温度在冻结20 d时都降到了0 ℃以下,在冻结40 d时都降到了-10 ℃以下。所得结果可为今后类似工程设计提供理论参考依据。
Finite element analysis has been used in the development and distribution of new freezing method pipe curtain temperature field by modeling 6 paths of development frozen soil wall thickness changes and closed the study. The main results are: 8 days round freezing cold soil curtain began to cross lap, and 30 days frozen soil pipe curtain has been formed. The average temperature of -18 ℃ 0.6m thick frozen wall, pipe curtain between 40 days average temperature -18 ℃ frozen soil wall thickness reaches 0.8m, and has developed into a trend of continuous freezing through pipe curtain wall. The freezing of 16 days or less 0 ℃ frozen soil wall thickness has reached 1m, and less -10 ℃ frozen soil wall thickness of up to 1m required frozen time of 35 days: steel and frozen soil interface in freezing temperatures on 20 days is below 0 ℃, and freezing 40 days is below -10 ℃. The results can provide a theoretical reference for future similar projects