青藏铁路可调控通风管路基温度场的三维非线性分析  

3-D Nonlinear Analysis of the Temperature Field of an Adjustable Ventilated Embankment in Qinghai-Tibet Railway

作　　者：李国玉[1] 李宁[1] 全晓娟[1] 杨黎明 

机构地区：[1]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 [2]甘肃路桥第二公路工程有限责任公司,甘肃兰州730050

出　　处：《冰川冻土》2005年第1期128-133,共6页Journal of Glaciology and Geocryology

基　　金：中国科学院知识创新工程重大项目(KZCX1 SW 04)资助

摘　　要：可调控通风管路基是一种理想的保护高温冻土的工程措施. 应用有限元法, 对青藏铁路普通通风管路基和可调控通风管路基在施工完10 a内的温度场变化进行了三维数值分析. 结果表明: 可调控通风管路基在夏季(8月份)0 ℃的等温线比普通通风管路基要高, 说明它的冻土上限抬升幅度较大,使冻土得到更好地保护, 并且其路基下面从第二年开始也不会出现融化层; 可调控通风管路基下面的冻土平均温度降到-1 ℃时的时间比普通通风管路基要早, 说明可调控通风管路基具有较好的降温速度和降温效果.The adjustable ventilated embankment, which is adopted in the Qinghai-Tibet Railway, is one of the ideal engineering measures to protect a warm frozen soil. In this paper, Finite Element Method has been used to operate a numerical analysis of 3-D temperature field and to make a comparison between the ordinary ventilated embankment and the adjustable ventilated embankment. It is found that the adjustable ventilated embankment can prevent the thermal entry from air into the ducts and the thawing of the permafrost beneath the embankment during summer, and that the location of 0 ℃ isotherm of the adjustable ventilated embankment is higher than that of the ordinary ventilated embankment in summer. The permafrost table of the adjustable ventilated embankment rises significantly. The permafrost underlying the embankment is protected better. Also the thawing bulb does not appear in summer. In addition, the time that the mean temperature of the permafrost underlying the adjustable ventilated embankment decreases below {-1} ℃ is much earlier than that underlying the ordinary ventilated embankment. These indicate that the cooling effect of the adjustable ventilated embankment on permafrost is better than that of the ordinary ventilated embankment.

关 键 词：青藏铁路 可调控通风管路基 温度场 三维非线性分析 

分 类 号：TU445[建筑科学—岩土工程]