摘要
季节冻土层中的地温呈非线性分布,改变了冻土墙形成时的初始温度条件以及形成后的结构形式。有季节冻土条件下形成深6m、厚1.4m的冻土墙较无季节冻土的情况可减少冻结时间15d,减少冷能消耗60%,经济上有极大优势。通过数值模拟,得到了能量消耗与时间关系曲线、冻结管热流密度与深度关系曲线、冻土墙的厚度与时间关系曲线、冻土墙的厚度与深度关系曲线等,可见季节冻土层的存在显著提高了冻土墙的厚度发展速度,减少了冻结时间,降低了冷能消耗。模拟了49种工况,对冻结管直径、冻结管间距、冻结时间、冻土墙平均温度、冻土墙厚度等数据进行了非线性回归分析,得到冻土墙厚度与时间成对数函数关系、平均温度与时间成反比例关系的相关表达式,为人工冻结技术的合理运用和推广提供了理论依据。
The existence of the seasonal frozen soil layer provides a favorable environment for the formation of the artificially frozen wall; also it changes the wall＇s configuration. To investigate the impact of the seasonal frozen soil layer on the formation of the frozen wall, 49 work conditions were simulat. The results show that to form a frozen wall which is 6 m depth and 1.4 m thichness in seasonal frozen area, the construction time can be reduced by 15 days and the consumption of energy can be reduced to 60 %. It has a significant economical predominance to form a frozen wall in frozen area. Seasonal frozen soil layer improved the expanding velocity of the frozen wall; reduced the consumption of energy and improved the wall＇s capacity to bear loads. Finally a nonlinear regression model to estimate the thickness and even temperature of the frozen wall is established. The results of present work provide a theoretical support and guide for the application of artificial ground freezing method in cold regions.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2009年第4期971-975,共5页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.40571032)资助。
关键词
人工冻土墙
非线性地温
季节冻土层
人工冻结法
artificially frozen wall
nonlinear ground temperature
seasonal frozen soil layer
ground freezing
