摘要
为研究线性加载条件下不同应力历史的饱和黏土的渗透性,利用改装后的GDS三轴仪进行了一维固结渗透联合试验,对陕西洛川粉质黏土重塑样的渗透系数变化规律进行了研究。研究结果表明,正常固结与超固结饱和黏土的渗透系数均随固结应力的增大而呈非线性减小,且两者的孔隙比与渗透系数随固结应力的变化趋势一致。处于超固结状态土体的压缩性和渗透性要比处于正常固结状态小得多。在同一固结应力下,渗透系数和孔隙比均随渗透压差的增大而减小。最后,将实测值与文献[12]中修正后的达西渗透系数公式、修正后的柯森-卡门公式、斯托克斯孔隙流渗透系数公式以及固结度渗透公式计算得到的渗透系数进行了比较。结果表明,用修正后的柯森–卡门渗透系数公式计算得到的渗透系数与实测值吻合较好,因此,推荐使用修正后的柯森–卡门渗透系数公式来预测洛川饱和黏土渗透系数。
To study the permeability of saturated clays with different stress histories under ramp loading,the one-dimensional consolidation and seepage tests are carried out using modified GDS triaxial apparatus,and the change of the permeability coefficient of remolded silty clay in Luochuan,Shaanxi Province is studied.The results show that permeability coefficients of normally and over-consolidated saturated clays decrease nonlinearly with the increase of the consolidation stress,and the void ratios of these two soils are consistent with the trend of change of the permeability coefficients with the consolidation stress.The compressibility and permeability of soil in the over-consolidated state are much smaller than that in the normally consolidated state.The permeability coefficient and void ratio decrease with the increase of the osmotic pressure difference under a constant consolidation stress.Finally,the measured values are compared with the permeability coefficients calculated by the modified Darcy permeability coefficient formula,modified Kozeny-Carman formula,Stokes porosity permeability coefficient formula and degree of consolidation and seepage formula in Ref.[12].The results reveal that the permeability coefficients calculated using the modified Kozeny-Carman formula are in good agreement with the measured values.Therefore,the modified Kozeny-Carman formula is recommended to predict the permeability coefficient of Luochuan saturated clay.
作者
张乐
党发宁
高俊
丁九龙
ZHANG Le;DANG Fa-ning;GAO Jun;DING Jiu-long(State Key Laboratory of Eco-hydraulics in Northwest Arid Region,Xi’an University of Technology,Xi'an,Shaanxi 710048,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2021年第4期1078-1087,共10页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51979225,No.51679199)
水利部公益性行业科研专项(No.201501034-04)
陕西省科技统筹创新工程重点实验室项目(No.2014SZS15-Z01)。
关键词
线性加载
正常固结饱和黏土
超固结饱和黏土
渗透系数
孔隙比
非线性固结渗透
ramp loading
normally consolidated saturated clay
over-consolidated saturated clay
permeability coefficient
void ratio
nonlinear consolidation and seepage
