【作者】 原思成； 韩利民； 张鲁新； 张先军；

【Author】 Yuan Sicheng Han Liming Zhang Luxin Zhang Xianjun(School of Civil & Architecture engineering, Beijing Jiaotong University, Beijing 100044;Administration Headquarters of Qinghai ?Tibet Railway Construction, Xining 810001;Lanzhou University, Lanzhou 730001)

【机构】 北京交通大学土木建筑工程学院； 兰州大学；

【摘要】 冻土区筑路技术问题的关键是冻土的热稳定性问题,这种热学问题的力学表现是路基变形问题。本文通过对填土路基修筑后土体冻融发生发展过程及相应阶段路基变形特征的分析,指出青藏铁路冻土区填土路基地温场形态控制了施工建设期间和其后长期运营期间的路基变形总量和横向差异变形总量。这些变形主要由冻土季节融化层土体的冻胀融沉变形、冻土压缩变形、冻土长期蠕变变形组成。工程监测、试验研究以及理论计算表明,采用调控地温场变化的路基结构,可以减少施工期和运营期路基变形,减小变形不均匀性,保证冻土区路基工程的长期稳定性,这一结论对青藏铁路冻土区路基工程设计的理论指导作用已经在工程实践中得到验证。更多还原

【Abstract】 The key problem of railway construction across the permafrost area is thermo stability of the ground. The construction disturbs the natural thermo balance and the thermo stability of permafrost. Thus the stability of the roadbed is influenced. In this paper, the freezing and melting course of the soil was analyzed, as well as corresponding deforming characteristics of roadbed. Based on the analysis, we could conclude that the status of ground temperature field of the roadbed controls total deforming of the roadbed. Engineering activities and observations show that if we use some kinds of structure of roadbed which could regulate the ground temperature field, we can decrease the problem caused by deforming of roadbed. Such principle has been affirmed during the course of Qinghai - Tibet Railway construction.更多还原