青藏直流输电工程粗粒冻土地基温度监测与分析

摘要
图/表
参考文献
相关文章 (15)

全文: PDF (1106 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要为分析青藏直流输电线路工程冻土地基的冻结情况及其对基础安全稳定性的影响，在青藏高原五道梁地区对装配式原型基础冻土地基进行1个冻融过程的地温监测，结合该地区气温资料，分析粗粒冻土地温随时间变化特点和沿深度分布情况。监测结果显示：地温呈周期性波动，振幅随深度增加而减小，原状和回填冻土地基上部均存在冻融状态交替的冻融活动层；监测期内基础底部冻土处于冻结状态，基础安全稳定；原状和回填冻土最大融化深度分别为3.0和3.2 m，通过建立地温估算公式，并利用地温变化幅值、均值等结果，得到原状多年冻土上限为3.1 m，与工程勘测和监测结果一致；建立冬季时高孔隙率回填冻土地基传热方程，分析地基传热性能和与孔隙率直接相关的地基中空气自然对流速度对地基回冻的影响。研究表明：冻土回填扰动加剧地温波动的振幅和增大冻土融化深度，但影响程度和范围有限；输电线路冻土装配式基础冬季施工，在冻融活动层深度内保持地基适当孔隙率，既可在冬季加速地基回冻，又可利用土体自然固结和融沉，提高压实度，从而在暖季减弱热量向地基深部扩散，有利于地基保持冻结。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章

关键词 ：土力学, 输电线路, 装配式基础, 冻土, 地温, 多年冻土上限

Abstract：To analyze refreezing of frozen ground and its influence on foundation stability in the Qinghai-Tibet DC Transmission Line Engineering，temperature monitoring for a freezing-thawing process is carried out for the assembling prototype foundations and frozen soil in Wudaoliang area on the Tibetan Plateau. Combining with atmospheric temperature data in the area，the ground temperature changing characteristics with time and distributing along the depth of undisturbed and backfill coarse-grained frozen soil are analyzed. Monitoring results show that：(1) Ground temperature is periodic fluctuation and its amplitude decreases with increase of depth. There is a freeze-thaw state alternating layer in the upper undisturbed and backfill soil. (2) In the monitoring period，the frozen soil below foundation slab is in frozen state and the foundations are stable. (3) The maximum thawing depths of undisturbed and backfill frozen soil are 3.0 and 3.2 m respectively. Through the establishment of ground temperature estimation formula，and based on the results of ground temperature change amplitude and mean value，etc.，it is obtained that the permafrost table is 3.1 m，which is consistent with the results of engineering survey and monitoring. (4) Using heat transfer theories，ground heat transfer model of high porosity frozen soil backfilled in winter is established. The heat transfer ability and air natural convection velocity effects on refreezing of ground are analyzed. The results indicate that：(1) Backfill disturbance of frozen soil aggravates temperature fluctuation amplitude and increases the thawing depth，but the effect degree and range are limited. (2) Construction of transmission lines in frozen soil and assembly foundations in winter and keeping proper porosity of the backfill frozen soil in freeze-thaw active layer are beneficial not only to accelerate the ground refreezing，but also to increase compaction degree because of soil natural consolidation and thawing settlement. So，the frozen state in the warmer seasons could keep while heat diffusion to deeper ground weakens.

Key words： soil mechanics transmission line assembly foundation frozen soil ground temperature permafrost table

收稿日期: 2012-03-01

引用本文:

程永锋1，丁士君1，鲁先龙1，谭蓉2. 青藏直流输电工程粗粒冻土地基温度监测与分析[J]. 岩石力学与工程学报, 2012, 31(11): 2363-2371.
CHENG Yongfeng1，DING Shijun1，LU Xianlong1，TAN Rong2. MONITORING AND ANALYSIS OF COARSE-GRAINED FROZEN SOIL TEMPERATURE IN QINGHAI-TIBET DC TRANSMISSION LINE ENGINEERING. , 2012, 31(11): 2363-2371.

链接本文:

http://www.rockmech.org/CN/Y2012/V31/I11/2363

[7]	齐吉琳，马巍. 冻融作用对超固结土强度的影响[J]. 岩土工程学报，2006，28(12)：2 082-2 086.(QI Jilin，MA Wei. Influence of freezing-thawing on strength of over consolidated soils[J]. Chinese Journal of Geotechnical Engineering，2006，28(12)：2 082-2086.(in Chinese)) " target="_blank">
[9]	蒋武军，葛修润. 双能量方程在通风路基多孔介质中的应用[J]. 岩石力学与工程学报，2006，25(6)：1 770-1 776.(JIANG Wujun，GE Xiurun. Application of double-energy equation to porous media of ventilated embankment[J]. Chinese Journal of Rock Mechanics and Engineering，2006，25(6)：1 770-1 776.(in Chinese)) " target="_blank">
[12]	卞晓琳，何平，吴青柏，等. 粒径对块石层自然对流特性影响的试验研究[J]. 中国铁路科学，2011，32(1)：1-6.(BIAN Xiaolin，HE Ping，WU Qingbai，et al. Experimental study on the influence of the particle diameter on the natural convection characteristics of the block stone layer[J]. China Railway Science，2011，32(1)：1-6.(in Chinese)) " target="_blank">
[14]	ZHANG M Y，LAI Y M，GAO Z H，et al. Influence of boundary conditions on the cooling effect of crushed-rock embankment in permafrost regions of Qinghai-Tibet Plateau[J]. Cold Regions Science and Technology，2006，44(3)：225-239. " target="_blank">
[16]	杨世铭，陶文铨. 传热学[M]. 4版. 北京：高等教育出版社，2006：33-200.(YANG Shiming，TAO Wenquan. Heat transfer[M]. 4th ed. Beijing：Higher Education Press，2006：33-200.(in Chinese)) " target="_blank">
[17]	中华人民共和国行业标准编写组. JGJ 118—98冻土地区建筑地基基础设计规范[S]. 北京：中国建筑工业出版社，2009.(The Professional Standards Compilation Group of People?s Republic of China. JGJ 118—98 Code for design of soil and foundation of building in frozen soil region[S]. Beijing：China Architecture and Building Press，2009.(in Chinese)) " target="_blank">
[19]	孙斌祥，徐学祖，赖远明，等. 多年冻土区碎石路堤冬季自然对流降温效应的演化机制[J]. 科学通报，2006，15(2)：211-219.(SUN Binxiang，XU Xuezu，LAI Yuanming，et al. Evolution mechanism of winter-time natural convection cooling effect in fractured-rock revetment embankments of permafrost region[J]. Chinese Science Bulletin，2006，15(2)：211-219.(in Chinese)) " target="_blank">
[1]	鲁先龙，程永锋，费香泽，等. 新疆皇吉220 kV输电线路天山段多年冻土工程特性研究[J]. 岩石力学与工程学报，2004，23(增1)：4 383-4 387.(LU Xianlong，CHENG Yongfeng，FEI Xiangze，et al. Field tests on mechanical characteristics of permafrost along Tianshan Section of Huangji 220 kV transmission line[J]. Chinese Journal of Rock Mechanics and Engineering，2004，23(Supp.1)：4 383-4 387.(in Chinese)) " target="_blank">
[11]	徐斆祖，孙斌祥，李东庆，等. 边界温度周期波动下块石的温度变化规律[J]. 岩土工程学报，2003，25(1)：91-95.(XU Xiaozu，SUN Binxiang，LI Dongqing，et al. Variation of temperature in ballasts under periodic fluctuation of boundary temperature[J]. Chinese Journal of Geotechnical Engineering，2003，25(1)：91-95.(in Chinese))
[15]	何树生，张明义，张耀，等. 多年冻土区开放块石护坡降温特性室内试验研究[J]. 铁道学报，2008，30(4)：54-58.(HE Shusheng，ZHANG Mingyi，ZHANG Yao，et al. Laboratory investigation on cooling characteristics of open block-stone revetment in permafrost regions[J]. Journal of the China Railway Society，2008，30(4)：54-58.(in Chinese)) " target="_blank">
[18]	GAO Z Q，FAN X G，BIAN L G. An analytical solution to one- dimensional thermal conduction-convection in soil[J]. Soil Science，2003，168(2)：99-107. " target="_blank">
[2]	吴紫汪，刘永智. 冻土地基与工程建筑[M]. 北京：海洋出版社，2005：1-6.(WU Ziwang，LIU Yongzhi. Frozen subsoil and engineering[M]. Beijing：Ocean Press，2005：1-6.(in Chinese)) " target="_blank">
[3]	陈肖柏，刘建坤，刘鸿绪，等. 土的冻结作用与地基[M]. 北京：科学出版社，2011：3-81.(CHEN Xiaobo，LIU Jiankun，LIU Hongxu，et al. Frost action of soil and foundation engineering[M]. Beijing：Science Press，2011：3-81.(in Chinese)) " target="_blank">
[4]	徐斆祖，王家澄，张立新. 冻土物理学[M]. 北京：科学出版社，2010：1-18.(XU Xiaozu，WANG Jiadeng，ZHANG Lixin. Frozen soil physics[M]. Beijing：Science Press，2010：1-18.(in Chinese)) " target="_blank">
[5]	程国栋. 冻土力学与工程的国际研究新进展[J]. 地球科学进展，2001，16(3)：293-299.(CHENG Guodong. International achievements of study on frozen soil mechanics and engineering[J]. Advance in Earth Sciences，2001，16(3)：293-299.(in Chinese))
[6]	ANDERSLAND O B，LADANYI B. 冻土工程[M]. 2版. 杨让宏，李勇，译. 北京：中国建筑工业出版社，2011：1-92. (ANDERSLAND O B，LADANYI B. Frozen ground engineering[M]. 2nd ed. Translated by YANG Ranghong，LI Yong. Beijing：China Architecture and Building Press，2011：1-92.(in Chinese)) " target="_blank">
[8]	NICHOLAS A B，DAVID C S . Cyclic freeze-thaw to enhance the stability of coal tailings[J]. Cold Regions Science and Technology，2009，55(3)：278-285. " target="_blank">
[10]	程国栋，赖远明，孙志忠，等. 碎石层的“热半导体”作用[J]. 冰川冻土，2007，29(1)：1-7.(CHENG Guodong，LAI Yuanming，SUN Zhizhong，et al. On the “Thermal diode” function of crushed rock layer[J]. Journal of Glaciology and Geocryology，2007，29(1)：1-7.(in Chinese))
[13]	张明义，赖远明，喻文兵，等. 封闭与开放抛石路堤降温效果及机制对比试验研究[J]. 岩石力学与工程学报，2005，24(15)：2 671-2 677. (ZHANG Mingyi，LAI Yuanming，YU Wenbing，et al. Contrast experimental study on cooling effect and mechanism between closed and open riprapped-embankments[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(15)：2 671-2 677.(in Chinese)) " target="_blank">