Analysis and experimental study on thixotropy of Tianjin soft clay
HUO Haifeng1,QI Lin1,LEI Huayang2,YU Ge3
(1. School of Airport Engineering,Civil Aviation University of China,Tianjin 300300,China;2. School of Civil
Engineering,Tianjin University,Tianjin 300072,China;3. School of Sino-European Aviation Engineering,
Civil Aviation University of China,Tianjin 300300,China)
Abstract:Vane shear tests on Tianjin soft clay were performed to obtain the strength of disturbed clay. The test results indicated that the strength change exhibited the positive thixotropy. The strength had a gain of 3.0 kPa after 100 minutes,then increased 1.8 kPa after 1 year. It would take 4 years at least for the disturbed clay to recover completely. The electrostatic force abiding the minimum-energy principle, the existence of the iron oxide (a significant component of cementing material) in Tianjin clay,the non-reversible grain cracking and the good drainage condition were found to promote the strength increasing. The direct shear tests showed that,as the normal pressure rised,the strength increment increased while the increment of thixotropic ratio decreased. The water content had little influence on thixotropic ratio.
[1] 步玉环,尤 军,姜林林. 触变性水泥浆体系研究与应用进展[J]. 石油钻探技术,2009,37(4):110–114.(BU Yuhuan,YOU Jun,JIANG Linlin. Research and application of thixotropic cement slurry[J]. Petroleum Drilling Techniques,2009,37(4):110–114.(in Chinese))
[2] BOSWELL P G H. A preliminary examination of the thixotropy of some sedimentary rocks[J]. Quarterly Journal of Geological Society,1948,104(4):499–526.
[3] SKEMPTON A W,NORTHEY R D. The sensitivity of clays[J]. Géotechnique,1952,3(1):30–53.
[4] 刘 科. 触变性研究新进展[J]. 胶体与聚合物,2003,21(3):31–38. (LIU Ke. New progress in studies on thixotropy[J]. Chinese Journal of Colloid and Polymer,2003,21(3):31–38.(in Chinese))
[5] 冯秀丽,周松望,林 霖,等. 现代黄河三角洲粉土触变性研究及其应用[J]. 中国海洋大学学报,2004,34(6):1 053–1 056.(FENG Xiuli,ZHOU Songwang,LIN Lin,et al. The thixotropy of silt in Huanghe delta[J]. Periodical of Ocean University of China,2004,34(6):1 053–1 056.(in Chinese))
[6] 刘崇宇,陈泉水,郑举功,等. Fe-Al-Mg-MMH/溪膨润土分散体系触变性研究[J]. 东华理工大学学报,2009,32(2):168–171.(LIU Chongyu,CHEN Quanshui,ZHENG Jugong,et al. The thixotropy of Ferric Aluminum Magnesium Hydroxide/Monmorillon ite suspension[J]. Journal of East China Institute of Technology,2009,32(2):168–171.(in Chinese))
[7] 李丽华,陈 轮,高盛焱. 翠湖湿地软土触变性试验研究[J]. 岩土力学,2010,31(3):765–768.(LI Lihua,CHEN Lun,GAO Shengyan. Experimental research on thixotropy of wetland soft soil in Cuihu[J]. Rock and Soil Mechanics,2010,31(3):765–768.(in Chinese))
[8] 李丽华,刘数华. 国外软土触变性研究[J]. 路基工程,2009,(5):15–17.(LI Lihua,LIU Shuhua. On soft soil thixotropy abroad[J]. Subgrade Engineering,2009,(5):15–17.(in Chinese))
[9] 张先伟,孔令伟,李 峻,等. 黏土触变过程中强度恢复的微观机制[J]. 岩土工程学报,2014,36(8):1 407–1 413.(ZHANG Xianwei,KONG Lingwei,LI Jun,et al. Microscopic mechanism of strength increase of clay during thixotropic process[J]. Chinese Journal of Geotechnical Engineering,2014,36(8):1 407–1 413.(in Chinese))
[10] 孔令伟,吕海波,汪 稔,等. 湛江海域结构性海洋土的工程特性及其微观机制[J]. 水利学报,2002,33(9):82–88.(KONG Lingwei,LU Haibo,WANG Ren,et al. Engineering properties and micro- mechanism of structural marine soil in Zhanjiang sea area[J]. Journal of Hydraulic Engineering,2002,33(9):82–88.(in Chinese))
[11] 姚贤良,程云生. 土壤物理学[M]. 北京:农业出版社,1986:13–22.(YAO Xianliang,CHENG Yunsheng. Soil physics[M]. Beijing:China Agriculture Press,1986:13–22.(in Chinese))
[12] 熊 毅. 土壤胶体:II土壤胶体研究法[M]. 北京:科学出版社,1983:241–303.(XIONG Yi. Soil colloids:II The investigation method on soil colloids[M]. Beijing:Science Press,1983:241–303.(in Chinese))
[13] FREDLUND D G. 非饱和土土力学[M]. 陈仲颐,张再明,陈愈炯等译. 北京:中国建筑工业出版社,1997:256–305.(FREDLUND D G. Soil mechanics for unsaturated soils[M]. Translated by CHEN Zhongyi,ZHANG Zaiming,CHEN Yujiong,et al. Beijing:China Architecture and Building Press,1993:256–305.(in Chinese))
[14] 汤连生. 从粒间吸力特性再认识非饱和土抗剪强度理论岩土工程学报[J]. 岩土工程学报,2001,23(4):412–417.(TANG Liansheng. New suggestion on shear strength in unsaturated soil based on suction between grains[J]. Chinese Journal of Geotechnical Engineering,2001,23(4):412–417.(in Chinese))
[15] 栾茂田,李顺群,杨 庆. 非饱和土的基质吸力和张力吸力[J]. 岩土工程学报,2006,28(7):863–868.(LUAN Maotian,LI Shunqun,YANG Qing. Matric suction and tension suction of unsaturated soils[J]. Chinese Journal of Geotechnical Engineering,2006,28(7):863–868.(in Chinese))