多年冻土区公路路基阴阳坡温度及变形差异分析

 基于青康公路阴阳坡效应显著路段——K369路段路基的地温、变形监测资料，研究路堤内阴阳坡温度场差异及其对冻土路堤变形以及路堤稳定性的影响，分析路基地温、变形特征及其相互关系。研究结果表明：(1) 冻土路基在横断面上的差异沉降变形和其下地温场分布的不对称状况密切相关，地温场状况及其变化控制和决定着冻土路基变形场的状况；(2) 坡向不同而引起的太阳辐射差异是造成阴阳坡热交换不对称的根本原因，也是造成路基横向差异沉降的根本原因；(3) 路基变形的发展较地温的发展有一个相对滞后的响应，这决定了路基最大沉降并不是发生在最大融化深度的时间。对有差异沉降的路基来说，阴阳坡两侧路基发生最大沉降的时间也不一致，阳坡一侧达到最大沉降的时间要滞后于阴坡。这种差异变形会随着时间加剧，最终导致路基纵向裂缝的发育进而严重影响路基的稳定性。

TEMPERATURE AND DEFORMATION DIFFERENCES BETWEEN SOUTHERN AND NORTHERN SLOPES OF HIGHWAY EMBANKMENT ON PERMAFROST

Based on the observation data of the embankment in test section K369，the characteristics of the ground temperature and the deformation of the embankment are analyzed；and the relationship between the ground temperature and the deformation is presented. The observation data indicate：(1) the embankment transverse deformation difference has close relationships with the ground temperature transverse difference of the embankment，and it is controlled by the ground temperature state and its variation；(2) the difference of solar radiant amount on slopes results in transverse thermal difference in the embankment，and also leads to the transverse uneven settlement difference；and (3) the development of embankment deformation lags behind the development of embankment temperature，so the time of the largest settlement deformation is not equal to that of the maximum thaw depth. For the embankment with uneven deformation，the times of the largest settlement deformation on two sides of embankment are different；and the time of the largest settlement deformation on the south side is later than that on the north side of the embankment. The deformation difference will be aggravated with time；and finally the embankment stability is affected by longitudinal cracks of embankment caused by asymmetric settlement of permafrost.