Please wait a minute...
JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE)  2014, Vol. 48 Issue (4): 679-685    DOI: 10.3785/j.issn.1008-973X.2014.04.018
    
Laboratory study on drainage mechanism of vacuum preloading method
ZHANG Yi-ping1, LI Jian1,2
1. College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China;
2. Zhangjiagang City Bureau of Construction Works, Zhangjiagang 215600, China
Download:   PDF(1728KB) HTML
Export: BibTeX | EndNote (RIS)      

Abstract  

Three groups of model tests were conducted for sandy soil to investigate the drainage mechanism in vacuum preloading and analyze the influence of different factors on the drainage effect. Experimental results show that the drainage by expansion of solution gas is also an important drainage mechanism in addition to the drainage by consolidation, but the drainage by vaporization can be ignored. The pore size and the content of dissolved gas greatly influence the drainage by expansion of solution gas. Pore size is too big or too small can weaken the drainage effect induced by expansion solution gas. The larger the content of dissolved gas is, the more the water drained out is.



Published: 03 September 2014
CLC:  TU 447  
Cite this article:

ZHANG Yi-ping, LI Jian. Laboratory study on drainage mechanism of vacuum preloading method. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(4): 679-685.

URL:

http://www.zjujournals.com/eng/10.3785/j.issn.1008-973X.2014.04.018     OR     http://www.zjujournals.com/eng/Y2014/V48/I4/679


 真空预压排水机制室内模型试验研究

针对砂性土设计3组真空预压室内模型试验,探讨真空预压过程中存在的排水机制,分析不同因素对排水机制的影响.试验结果表明,在真空预压过程中,除固结排水外,溶解气膨胀驱水也是一种重要的排水机制,而蒸发所引起的排水可以忽略不计.试样孔隙大小、水中溶解气含量是影响溶解气膨胀驱水效果的主要因素,孔隙过大或过小都会削弱溶解气膨胀驱水的作用,溶解气含量越大,则溶解气的膨胀驱水效果越好.

[1] SAOWAPAKPIBOON J, BERGADO D T, YOUWAI S, et al. Measured and predicted performance of prefabricated vertical drains (PVDs) with and without vacuum preloading [J]. Geotextiles and Geomembranes, 2010, 28(1): 1-11.
[2] MESRI G, KHAN A Q. Ground improvement using vacuum loading together with vertical drains [J]. Journal of Geotechnical and Geoenvironmental Engineering, 2012, 136(6): 680-689.
[3] ROBINSON R G, INDRARATNA B, RUJIKIATKAMJORN C. Final state of soils under vacuum preloading [J]. Canadian Geotechnical Journal, 2012, 49(6): 729-739.
[4] 陈环.真空预压法机理研究十年[J]. 港口工程, 1991(4): 17-26.
CHEN Huan. Ten years study on mechanism of vacuum preloading method [J]. Port Engineering, 1991 (4): 17-26.
[5] KJELLMAN W. Consolidation of clay by mean of atmospheric pressure [C]∥ Proceeding of Conference on Soil Stabilization. Cambridge: MIT, 1953: 258-263.
[6] 董志良. 堆载及真空预压砂井地基固结解析理论[J]. 水运工程, 1992(9): 1-7.
DONG Zhi-liang. Consolidation theory of sand drain foundation with loading and vacuum preloading [J]. Port and Waterway Engineering, 1992(9): 17.
[7] INDRARATNA B, RUJIKIATKAMJORN C, SATHANANTHAN I. Analytical and numerical solutions for a single vertical drain including the affects of vacuum preloading [J]. Canadian Geotechnical Journal, 2005, 42(4): 994-1014.
[8] 张仪萍,严露,俞亚南,等. 真空预压加固软土地基变形与固结计算研究[J]. 岩土力学, 2011, 32(增刊1): 149-154.
ZHANG Yi-ping, YAN Lu, YU Ya-nan, et al. Solutions for settlement and consolidation of soft ground with vacuum preloading [J]. Rock and Soil Mechanics, 2011, 32 (supple.1): 149-154.
[9] 龚晓南,岑仰润. 真空预压加固软土地基机理探讨[J]. 哈尔滨建筑大学学报, 2002, 35(2): 7-10.
GONG Xiao-nan, CEN Yang-run. Mechanism of vacuum preloading [J]. Journal of Harbin University of Civil Engineering and Architecture, 2002, 35(2): 7-10.
[10] 辜清华,李志勇,何良德. 真空预压中地下水位变化的理论探讨[J]. 石家庄铁道学院学报:自然科学版, 2007, 20(3): 102-105.
GU Qing-hua, LI Zhi-yong, HE Liang-de. Theoretical discussion on groundwater level change in vacuum preloading [J]. Journal of Shijiazhuang Railway Institute: Natural Science, 2007, 20(3): 102-105.
[11] 邱青长,莫海鸿,董志良,等. 真空预压地基非饱和带探讨[J]. 岩石力学与工程学报, 2006, 25(增2): 3539-3544.
QIU Qing-chang, MO Hai-hong, DONG Zhi-liang, et al. Discussion on unsaturated zone in soft ground improved by vacuum preloading [J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25 (supple.2): 3539-3544.
[12] 明经平,赵维炳. 真空预压法加固软基的排水机制研究[J]. 岩土工程学报, 2008, 30(12): 1821-1825.
MING Jing-ping, ZHAO Wei-bing. Mechanism of drainage in vacuum preloading [J]. Chinese Journal of Geotechnical Engineering, 2008, 30(12): 1821-1825.
[13] 颜永国. 真空荷载下不同颗粒级配软土真空度传递规律试验研究[J]. 水运工程, 2010(10): 109-112.
YAN Yong-guo. Experimental study on vacuum degree transfer law of soft clay of different grain size grading under vacuum preloading [J]. Port and Waterway Engineering, 2010(10): 109-112.

[1] TAN Yong, KANG Zhi jun, WEI Bin, DENG Gang. Case study on deep excavation for metro ventilation shaft in Shanghai soft clay[J]. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2016, 50(6): 1048-1055.
[2] BAO Shu feng, DONG Zhi liang, LOU Yan, MO Hai hong, CHEN Ping shan, ZHOU Hong xin, LUO Yan. Laboratory research on new improvement technology of newly hydraulic reclamation mud with high clay content Ⅱ[J]. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2015, 49(9): 1707-1715.
[3] WANG Chi, XU Yong-fu, YE Guan-lin. Analysis of work characteristics of concrete-cored DCM pile composite foundation[J]. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(9): 1610-1617.
[4] XIE Xin-yu, HUANG Jie-qing, WANG Wen-jun, LI Jin-zhu. Influence of weight of soils on nonlinear finite strain consolidation for Ningbo soft clay[J]. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(5): 827-834.