渗流对多年冻土区路基温度场影响的数值模拟

Numerical Simulation of the Infulance of Seepage on Temperature Field of Roadbed in Permafrost Regions

运用传热学理论和渗流理论导出了路堤侧向有地表积水人渗情形下，多年冻土区路基温度场渗流场耦合作用的控制微分方程，然后以现场观测资料为基础，用Galerkin有限元方法对青康公路（214国道）花石峡冻土研究站1号试验路段路基温度场未来可能的变化状态进行了数值预报结果表明，若无渗流作用，5a后路堤左侧天然地表、路堤堤身和路堤右侧天然地表的最大季节融深分别为1.4m，3．2m和1．4m；若有渗流作用，则分别为1．4m，3．6m和1．6m.路堤侧向积水的渗流作用加深了路堤的季节融化深度，且距水源水平距离越近的地方最大季节融化深度也越大.

This paper discusses the influence of seepage of surface water in the sides of embankment on the temperature field of roadbed in permafrost regions. First, a mathematical model is established based on the heat transfer theory and seepage theory.Then, based on the observed data, the variation process of temperature field in the experimental roadbed,which is in Huashixia along the Qinghai-KangdingHighway in the Tibetan Plateau, after five years fromthe present is simulated in terms of Galerkin finite element method. The prediction results show that in case of no seepage effect, the maximum thawing deepths of ground in left sides of embankment, embankment itself and right side of embankment in the fifth year are l.4 m, 3.2 m, l.4 m and in case of seepage effect they are 1.4 m, 3.6 m, 1.6 m, respectively. The seepage of surface water in the sides of embankment will deepen the maximum thawing depth, and the nearer the boundary of roadbed in horizonal direction to the headwaiers, the deeper the maximum thawing depth in the vertical direction is.