青藏铁路路基下多年冻土演化特征及规律研究  

Evolution Features and Laws of Permafrost Under Subgrade of Qinghai-Tibet Railway

作　　者：杨永鹏 孟进宝 韩龙武 李勇 YANG Yongpeng;MENG Jinbao;HAN Longwu;LI Yong(Northwest Research Institute Co. Ltd. of C.R.E.C Lanzhou Gansu 730000 China;Qinghai Province Key Laboratory ofPermafrost and Environmental Engineering Golmud Qinghai 816000 China)

机构地区：[1]中铁西北科学研究院有限公司,甘肃兰州730000 [2]青海省冻土与环境工程重点实验室,青海格尔木816000

出　　处：《铁道建筑》2018年第5期81-86,共6页Railway Engineering

基　　金：中国中铁股份有限公司科学技术项目(2013-重大-20-1);中国铁路总公司科技研究开发计划(2016G003-D);科技部科研院所科技开发专项资金项目(2011EG123262)

摘　　要：通过对青藏铁路多年冻土区长期监测系统多年来的大量实测数据进行分析,研究了青藏铁路路基下多年冻土演化特征及规律。研究结果表明:青藏铁路沿线气温逐年升高,降水量、冻结指数和融化指数逐年增大,暖冬现象明显,地表温度年升高率达到0.06℃/年;沿线多年冻土区2007—2013年间冻土天然上限下移的达91%,不同深度处的地温整体处于升温状态;青藏铁路路基下多年冻土也发生了升温退化,在2007年冻土人工上限相对原天然上限均抬升的占81%,路基下多年冻土退化明显滞后于天然场地;片石路基、热棒路基等主动降温措施效果明显,保证了青藏铁路多年冻土路基工程的稳定。Through the analysis of a large amount of measured data from long term monitoring system in permafrost regions of Qinghai-Tibet railway for many years, the evolution features and laws of permafrost under the subgrade of Qinghai-Tibet railway were studied. The results show that,along the Qinghai-Tibet railway,the temperature,precipitation, freezing index and melting index increase year by year.The warm winter phenomenon is obvious,and the annual increase rate of ground temperature reaches 0.06 ℃/year. The ratios of permafrost whose natural upper limits decrease reach to 91%,and the ground temperatures at different depths are in the heating state.The permafrost under subgrade of Qinghai-Tibet railway has also undergone a heat degradation. In 2007,The ratios of permafrost whose artificial upper limits increase relative to the original natural limits reach to 81%.The degradation of permafrost under subgrade obviously lags behind the natural site. The engineering measures such as the block stone subgrade and the thermal probe subgrade used to protect permafrost in Qinghai-Tibet railway permafrost area are obviously effective,which guarantee the stability of permafrost subgrade engineering.

关 键 词：青藏铁路 路基 多年冻土 地温 冻土上限 片石路基 热棒路基 

分 类 号：U416.168[交通运输工程—道路与铁道工程]