不同厚度块石路堤对冻土路基冷却效果对比研究.pdf

第 25 卷 增 1 岩石力学与工程学报 Vol.25 Supp.1 2006 年2 月 Chinese Journal of Rock Mechanics and Engineering Feb. ，2006 不同厚度块石路堤对冻土路基冷却效果对比研究 1，2 1 1 王爱国 ，马 巍 ，王大雁 (1. 中国科学院 寒区旱区环境与工程研究所冻土工程国家重点实验室，甘肃 兰州 730000 ；2. 甘肃省地震局，甘肃 兰州 730000) 摘要：用数值模拟的方法计算了同一工程环境下块石路堤不同块石厚度情况的路基温度场随时间的变化。对比分 析显示：块石路堤均具有主动冷却路基的作用；由于边坡效应的存在，对一定的工程环境和设计，块石路堤存在 最优块石厚度，使冻土路基的冻结强度和多年冻土上限抬升达到最佳。块石太薄，块石中空气的循环达不到最大 制冷能力；块石太厚，边坡效应将导致空气的对流存在多向流动环，反而使隔热和制冷能力均减弱。 关键词：土力学；块石路堤；冷却效果；青藏铁路；数值模拟；边坡效应 中图分类号：TU 445 文献标识码：A 文章编号：1000 –6915(2006)增1 –3283 –06 COMPARISON STUDY ON COOLING EFFECT OF FROZEN-SOIL FOUNDATION ON BLOCK-STONE RAILWAY EMBANKMENT WITH DIFFERENT THICKNESS OF BLOCK-STONE 1，2 1 1 WANG Aiguo ，MA Wei ，WANG Dayan (1. State Key Laboratory of Frozen Soil Engineering ，Cold and Arid Regions Environmental and Engineering Research Institute， Chinese Academy of Sciences，Lanzhou 730000 ，China；2. Gansu Seismological Bureau，Lanzhou 730000，China) Abstract ：By numerical stimulation the temperature distribution were obtained in block-stone embankment with block-stone in different thicknesses. The comparative analyses show that block-stone embankment has well active cooling effect on the railway foundation by raising the permafrost table and decreasing the permafrost temperature. For a certain construction environment and a certain construction design there is an optimal thickness of block stone which will freeze the foundation most strongly and raise the permafrost table maximally. The cause is the slope effect of embankment and the thickness of block-stone.