Permafrost

the water leakage hazard in cold region tunnels.
Key words:The cold region tunnel, Water leakage, Hazard chain, the chain breakage using the
ripped stone
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Study on the ripped-stone method to the chain breakage of the water
leakage hazard in Kunlun mountain tunnel
Xue-fu Zhang
(1. School of Civil Engineering and Architecture, Chongqing Jiaotong University, Chongqing 400074,
China;2. State Key Laboratory of Frozen Soil Engineering, Cold & Arid Regions Environmental and
Engineering Research Institute, Chinese Academy of Sciences, Gansu Lanzhou 730000,China)
Abstract:The paper whose title is The elementary study on the chain-styled mechanism and the
new-typed method to the chain breakage of the water leakage hazard in Kunlun mountain
tunnel presents a new-typed method,using the ripped stone, to the chain breakage of the water
leakage hazard in cold region tunnels. And the design of the method is shown. But the theoretic
foundation and the feasibility of the method are not analyzed in that paper. In allusion to these
problems, according to the essential theories of heat transfer and seepage, considering the
coupled effects of seepage field and temperature field, a three-dimensional computational
model of the coupled problem is given. The finite element formulae of this problem are
obtained by Galerkin's method. And the computer program of the finite element is written.
Using this model and the computer program, three-dimensional nonlinear analysises for the
coupled problem of seepage field and temperature field of the flat segment DK977+578~
DK977+682 in Kunlun mountain tunnel on Qinghai-Tibet Railway are made under the two
conditions of using the ripped-stone method and not using the ripped-stone method. The results
show that it is feasible that the ripped-stone method is used for breaking the chain of the water
leakage hazard in the permafrost tunnels. So, the theoretic foundation of the ripped-stone
method is provided for its application and design in cold region tunnels.
Key words:The permafrost tunnels, Seepage field, The coupled problem, The chain breakage
using the ripped stone method, Three-dimensional nonlinear analysis.
Analysis of the Combined Effect of Thermal Insulation and
Thermosyphon for Embankment Cooling in Qinghai-Tibet Railway
Ya-hu Tian,Jian-kun Liu
(School of Civil Engineering and Architecture, Beijing Jiaotong University, Beijing 100044, China)
Abstract: The thermosyphon and the thermal insulation layer are widely used in the roadbed
engineering of Qinghai-Tibet railway separately. The measure protecting permafrost using
thermal insulation layer is a passive way, which has limitations. The insulation can prevent
outer thermal energy from penetrating the embankment in warm season, while in cold season it