COMPRESSIBILITY AND PERMEABILITY OF KAOLIN-BENTONITE BACKFILLS AT DIFFERENT INITIAL WATER CONTENT
Soil-bentonite (SB) vertical cutoff walls are effective and economical as engineering barriers for contaminant containment.Generally,high water content is needed for SB backfills to achieve target slumps in a range of 100 mm to 150 mm for the purpose of workability.In this study,a series of one-dimensional consolidation tests are performed to investigate the compressibility and permeability characteristics of kaolin-bentonite (KB) mixture as vertical cutoff wall backfills at varied initial water contents (w0),ranging from 0.75 to 1.75 times the liquid limit (wL) of KB.The bentonite contents of the KB backfills are 5%,10%,and 15% by dry weight.The results indicate that w0 has noticeable influence on the compression behavior of KB backfills in in terms of shapes of e-lg(r) curves and relationship between compression index (Cc) and wL.It is found that with the use of an altemative parameter,compression ratio (CR)instead of Cc,the degree of effect of w0 on the compressibility is marginal.The results are further discussed with the reference to the intrinsic compression line proposed by Burland.The data are well consistent with Burland s intrinsic compression line when the effective vertical stress is greater than about 50kPa,while a slight divergence exists at a vertical effective stress lower than 50kPa.The constants of intrinsic compressibility (Cc* and e100*) noticeably deviate from the empirical equations suggested by Burland,which is mainly attributed to the influence of w(0) and differences in the soil mineralogy.
slurry cutoff wall consolidation compressibility permeability
RIDONG FAN YANJUN DU SONGYU LIU
Institute of Geotechnical Engineering,Southeast University,Nanjing,210096,China
国际会议
5th China-Japan Geotechnical Symposium(第五届中日岩土工程学术会议)
成都
英文
113-117
2013-05-18（万方平台首次上网日期，不代表论文的发表时间）