Research On The Physical Properties Of Loess Mud Dehydration-consolidation Process

The soil of Baowagou near Sunning village of Zhidan County Yanan city were takenas experimental materials, prepare three types soil-water ratio(the soil-water ratio was1.5,2.0,2.5) mud,simulate the mud force conditions(0kpa and90kpa) at different depth of adam,maesrsure the coefficient of permeability, shear strength and consolidationcharacteristic of mud during in the process of dehydration consolidation. Researchobjective aims at researching and analyzing the law of dam physical properties changesduring in the process of dehydration consolidation,in order to provide theoretical basis forstability analysis of slurry-fall dams.Thus,it can enrich and develop the theory ofslurry-fall dams.In the paper, the main results were as follows:(1) The mud coefficient of permeability test results show the mud has lowercoefficient of permeability. The mud coefficient of permeability of different soil-waterratio decreased with increasing the dehydration consolidation time, especially thesoil-water ratio was1.5. The mud coefficient of permeability decreased with increasingtheir soil-water ratio and the mud-loading can reduce the coefficient of permeability ofmud significantly.(2) The mud shear strength test results show the curves of shear stress and sheardeform action presented no obvious relationship under the different soil-water ratio mudconditions. The mud corresponding shear stress increases when shear failure with thewater contents of mud increase and the mud shear strength was increases with the watercontents of mud increase,and the influence of water contents on cohesion bigger thannatural angle of repose. The shear stress with no load mud increases rapidly before theshear displacement was2mm,but the shear stress of mud-loading increases rapidly beforethe shear displacement was3mm. The shear strength was highest under condition of themud soil-water ratio was2.0in a certain water content without no load, however the shearstrength of mud-loading was highest when the soil-water ratio was2.5. The shear strengthof no load mud is mainly affected by water content, the soil-water ratio took the secondplace, the shear strength of mud-loading is only affected by water content.(3) The mud consolidation characteristic test results show that the void ratio of different soil-water mud was decrease with increase of lgp, the relationship between voidratio with vertical pressure and lgp presented quadratic function with different soil-watermud,and the relationship is significant. The compressibility of different soil-water ratiomud was was increases with the vertical pressure increase, but the compression modulus ofdifferent soil-water ratio mud was was increases with the vertical pressure increase. Underthe vertical pressure is0.025~0.05Mpa, the compressibility of mud decrease rapidly andthe compression modulus of mud increase rapidly. The compressibility and the modules ofmud were decreased slowly when the pressure was greater than0.05Mpa. Thecompression index of no load mud was greater than the compression index of mud-loadingin a certain soil-water ratio and water content. Compression index of mud was the smallest,the deformation of mud reduced and gradually stabilized when the soil-water ratio was2.5.