Long-term thermal regimes of the Qinghai-Tibet Railway embankments in plateau permafrost regions  

作　　者：NIU Fu un LIU MingHao CHENG GuoDong LIN ZhanJu LUO Jing YIN GuoAn 

机构地区：[1]State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences [2]Key Laboratory of Highway Construction & Maintenance Technology in Permafrost Region, Ministry of Transport,CCCC First Highway Consultants Co.Ltd [3]University of Chinese Academy of Sciences

出　　处：《Science China Earth Sciences》2015年第9期1669-1676,共8页中国科学（地球科学英文版）

基　　金：supported by the National Basic Research Program of China(Grant No.2012CB026101);the Western Project Program of the Chinese Academy of Sciences(Grant No.KZCX2-XB3-19);the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.41121061);the National Sci-Tech Support Plan(Grant No.2014BAG05B05)

摘　　要：Ten years of ground temperature data(2003–2013) indicate that the long-term thermal regimes within embankments of the Qinghai-Tibet Railway(QTR) vary significantly with different embankment structures. Obvious asymmetries exist in the ground temperature fields within the traditional embankment(TE) and the crushed-rock basement embankment(CRBE). Measurements indicate that the TE and CRBE are not conducive to maintaining thermal stability. In contrast, the ground temperature fields of both the crushed-rock sloped embankment(CRSE) and the U-shaped crushed-rock embankment(UCRE) were symmetrical. However, the UCRE gave better thermal stability than the CRSE because slow warming of deep permafrost was observed under the CRSE. Therefore, the UCRE has the best long-term effect of decreasing ground temperature and improving the symmetry of the temperature field. More generally, it is concluded that construction using the cooling-roadbed principle meets the design requirements for long-term stability of the railway and for train transport speeds of 100 km h?1. However, temperature differences between the two shoulders, which exist in all embankments shoulders, may cause potential uneven settlement and might require maintenance.Ten years of ground temperature data （2003-2013） indicate that the long-term thermal regimes within embankments of the Qinghai-Tibet Railway （QTR） vary significantly with different embankment structures. Obvious asymmetries exist in the ground temperature fields within the traditional embankment （TE） and the crushed-rock basement embankment （CRBE）. Measurements indicate that the TE and CRBE are not conducive to maintaining thermal stability. In contrast, the ground tem- perature fields of both the crushed-rock sloped embankment （CRSE） and the U-shaped crushed-rock embankment （UCRE） were symmetrical. However, the UCRE gave better thermal stability than the CRSE because slow warming of deep permafrost was observed under the CRSE. Therefore, the UCRE has the best long-term effect of decreasing ground temperature and im- proving the symmetry of the temperature field. More generally, it is concluded that construction using the cooling-roadbed principle meets the design requirements for long-term stability of the railway and for train transport speeds of 100 km h^-1. However, temperature differences between the two shoulders, which exist in all embankments shoulders, may cause potential uneven settlement and might require maintenance.

关 键 词：Qinghai-Tibet Railway PERMAFROST embankment structure thermal regime long-term stability 

分 类 号：U213.1[交通运输工程—道路与铁道工程]