摘要
To better understand the salinity effect on the compaction behaviour of soil,standard Proctor compaction test was conducted on soil samples with different salinities.Matric suction and small-strain shear modulus,G_(max),were determined and pore size distribution was also investigated on samples statically compacted at different water contents.Results showed that with the decrease of soil salinity from initial value of 2.1‰(g of salt/kg of dry soil)to zero,the maximum dry density increased and the optimum water content decreased,whereas there was no significant change with the increase of soil salinity from 2.1‰ to 6.76‰.Interestingly,it was observed that G_(max) also decreased when the soil salinity decreased from initial value of 2.1‰ to zero and kept almost constant when the soil salinity increased from 2.1‰ to 6.76‰,for dry samples with similar matric suction and also for samples compacted at optimum state and on wet side whose matric suctions were slightly different due to the difference in remoulded water content.Furthermore,the effect of salinity on compaction behaviour and G_(max) decreased for samples compacted from dry side to wet side.The pore size distribution exhibited bi-modal characteristics with two populations of micro-and macro-pores not only for samples compacted on dry side and at optimum state,but also for those compacted on wet side.Further examination showed that the modal size of micro-pores shifted to lower values and that of macro-pores shifted to higher values for saline soil compared to the soil without salt.
基金
the China Scholarship Council(CSC)
Ecole des Ponts ParisTech(ENPC)
INRAE for their financial support。
作者简介
Corresponding author:Yu-Jun Cui,obtained his BSc degree in Civil Engineering from Tongji University,China,in 1984,his Master degree in Mechanics applied to Constructions from Ecole des Ponts ParisTech(ENPC),France,in 1989 and his PhD in Unsaturated Soil Mechanics in 1993,also from Ecole des Ponts ParisTech(ENPC).He was employed by ENPC immediately after his PhD as an assistant researcher in the Laboratory of Soil Mechanics(CERMES)now becoming Geotechnique Group of Laboratoire Navier.He passed his Habilitation to Direct Research in Civil Engineering at University of Marne La Vallee,France,in 2000,and obtained the position of professor of ENPC in 2005.He has been Head of Master MSROE(Mecanique des Sols,des Roches et des Ouvrages dans leur Environnement)since 2004.His research interests cover unsaturated soil mechanics,laboratory testing,constitutive modelling,environmental geotechnics,railway geotechnics,nuclear waste disposal,lime/cement stabilized soils,soilevegetationeatmosphere interaction,compaction of agricultural soils,etc.E-mail address:yu-jun.cui@enpc.fr。
