路基坡脚积水对多年冻土路基稳定性的影响研究进展

Progress in the research of the influence of ponding by embankment on the stability of embankment in permafrost regions

多年冻土路基的稳定性很大程度上取决于其下伏多年冻土层的热稳定性.当融雪、降雨或人为等外界因素形成的路基坡脚积水持续一段时间后,这些积水可能通过入渗对流换热、热边界侵蚀、补给冻胀水分等方式加剧或诱发多年冻土路基热稳定性的下降和丧失.通过回顾国内外相关文献,从影响多年冻土路基稳定性的因素、积水对路基活动层冻融过程中水分迁移的影响、热融湖塘类积水对冻土路基的热影响、降雨和融雪积水入渗对冻土路基的热影响等方面,归纳总结了坡脚积水对多年冻土路基影响方面的研究进展;在此基础上,提出了对此问题进一步深入的研究展望和探讨.

The stability of embankment in permafrost regions depends on the thermal stability of frozen soil under it largely. With the pondings caused by snowmelt, rainfall or other artificial factors beside the embankment for a long time, the water of the ponding can aggravate or induce the decreasing and loss of the thermal stability through infiltration with convection conduction, thermal boundary erosion, providing water for frost heaving, etc. In this paper, the related literatures from domestic and abroad are summarized to understand the research status of the influence of the pondings on the stability of permafrost embankment. These literatures involve the factors of affecting the stability of permafrost subgrade, the influence of water from ponding on the active layer and the thermal effect of the water from thermokarst lake, the seepage water from rainfall, snowmelt or other ponding on permafrost embankment. Based on this, the further outlook and research about this problem are proposed.