双圈管黏土冻结壁形成过程冻胀力模型试验研究  

Model Test of Frost Heaving Pressure during Formation of Clay Freezing Wall with Two-Cycle Freezing-Tube

作　　者：李海鹏[1,2] 杨维好[1,2] 黄家会[2] 宋雷[1,2] 张涛[2] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008 [2]中国矿业大学力学与建筑工程学院,江苏徐州221116

出　　处：《冰川冻土》2011年第4期801-806,共6页Journal of Glaciology and Geocryology

基　　金：国家科技支撑计划项目(2006BAB16B01);国家自然科学基金项目(40801032;40604015)资助

摘　　要：基于相似理论,开展了双圈管同步冻结条件下黏土冻结壁形成过程冻胀力模型试验研究.在试验条件下黏土冻结壁交圈顺序为外圈管、内圈管,两圈管之间,冻结310 d后冻结壁发展到井帮位置.随时间发展,外圈管内侧温度分布逐渐均匀,而外圈管外侧仍存在较大温度梯度.结果表明:冻胀力的发展变化与冻结温度场密切相关,且表现出显著的时空不均匀性.在冻结壁形成过程中,两圈管之间首先出现冻胀力,之后逐渐由两圈管向外扩展,两圈管之间与外侧冻胀力的差异程度随时间增长而增大.冻结初期井心附近应力随时间增长而降低,至190 d开始出现冻胀力.之后,随冻结时间增长,井心与两圈管之间的冻胀应力场梯度减小,而两圈管之间与冻结壁外边界仍存在较高梯度.Based on similarity theory, a model test was carried out of frost heaving pressure during the formation of clay freezing wall with two-cycle freezing-tube. In the test, closured freezing wall firstly formed in the outer cycle of the freezingtube, and then formed in the inner cycle of the freezing-tube, lastly formed between the two cycles. Temperature difference between the inside the outer cycles decreased gradually. However, there was still at high temperature gradient outside of the outer cycle until the test finished. It is found that the frost heaving pressure closely related with temperature. The frost heaving pressure firstly developed between the two cycles, and then developed outwards from the two cycles. At the beginning, the stress in the centre of shaft was decreasing and frost heaving pressure took place after 190 d. The difference of frost heaving pressure was decreasing with time between the centre of shaft and the middle of the two cycles, while there was a higher stress gradient between the outside of the outer cycle and the middle of the two cycles.

关 键 词：冻结壁 双圈管 黏土 温度场 冻胀力 

分 类 号：P642.14[天文地球—工程地质学]