青藏高原高温高含冰量冻土压缩试验研究  

Compression experimental research on warm and ice-rich permafrost on the Qinghai-Tibet Plateau

作　　者：阮国锋[1] 张建明[1] 刘世伟 张虎[1] 苏凯[1] 郑波[3] 

机构地区：[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]甘肃省水利水电勘察设计研究院,甘肃兰州730000 [3]中铁西南科学研究院有限公司,四川成都610031

出　　处：《水文地质工程地质》2014年第2期50-56,共7页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金(40971045);冻土工程国家重点实验室自主研究课题(SKLFSE-ZY-02-6);国家重点基础研究发展计划(2012CB026106)

摘　　要：采用恒温变载和恒载变温两种压缩试验方法研究了青藏高原高温高含冰量冻土(WIFS)的变形特性,得到了不同温度下的压缩指标。试验结果表明:(1)高温高含冰量冻土的压缩性具有很大的量级,压缩指数都在0.15以上。(2)恒温变载(CTSL)实验条件下,压缩系数都在0.2MPa-1以上。恒载变温(CLST)实验条件下,当温度为-1.5℃时,压缩系数为0.04MPa-1,而当温度升高到-0.3℃时,冻土压缩系数变为0.29MPa-1。(3)在分级加载试验中应变最大可达10%,在阶梯型升温条件下应变最大可达8%。通过探讨分析,认为青藏高原高温高含冰量冻土属于中高等压缩性土,青藏铁路在其以后的运营中必须加强必要的维护和密切的动态变形监测。In order to investigate the deformation behaviour of warm and ice-rich permafrost on the QinghaiTibet Plateau, compression tests were conducted in laboratory using two methods： （1） a traditional compression test under a constant temperature and a stepped load （CTSL） , and （2） a compression test under a constant load and a stepped temperature （CLST）. Compression index for warm and ice-rich frozen soil （ WIFS） was obtained correspondingly under various temperatures. The test results show that： （1） compression deformation of WIFS is of considerable magnitude, and compressibility index aer all above o. 15 ; （2） compressibility coefficients are all above o. 2MPa^ -1 under CTSL. Under CLST, when temperature is at - 1. 5℃ and - 0. 3℃ ,the compressibility coefficients are 0. 04MPa ^ -1 and 0. 29 MPa^ -1 , respectively; （3） in the CTSL and CLST models, the maximum value of strain is as high as 10% and 8 %, respectively. It is proposed after discussion that the deformation of the Qinghai-Tibet railway must be dynamically monitored during its operation.

关 键 词：高温高含冰量冻土 压缩指数 压缩系数 

分 类 号：P642.14[天文地球—工程地质学] TU445[天文地球—地质矿产勘探]