多年冻土块石路基蠕变变形研究

Study on creep deformation of permafrost block stone roadbed

由于全球气候变化,以及大规模的寒区工程建设,打破了多年冻土地区原有的地表能量平衡,导致地温升高,冻土上限逐年下降,高温冻土层厚度不断扩大,冻土蠕变变形愈加剧烈。本文通过结合青藏铁路典型多年冻土块石路基路段特征,采用变换等效导热系数法来综合考虑块石通风区的换热性质,数值模拟多年冻土路基多年蠕变变形,进行其10年、20年和30年的温度场和变形场预测,分析其蠕变情况。

Due to the global climate change and large-scale cold-zone project construction,the original surface energy balance in permafrost regions is broken,resulting in an increase in ground temperature,an annual decrease in the upper limit of frozen soil,and an increase in the thickness of high-temperature frozen soil layers, the creep deformation of frozen soil is more and more severe. In this paper,by combining the characteristics of the typical permafrost block stone roadbed section of the Qinghai-Tibet Railway,the transforming equivalent thermal conductivity method is used to comprehensively consider the heat transfer properties of the block stone ventilation zone. After that,the temperature field predictions of 10 years,20 years and 30 years are performed. Their creep situations are also analyzed.