The semi-analytical solutions to Fredlund and Hasan＇s one-dimensional （1D） consolidation for unsaturated soils with a semi-permeable drainage boundary are pre- seated. Two variables are introduced to transform the ...The semi-analytical solutions to Fredlund and Hasan＇s one-dimensional （1D） consolidation for unsaturated soils with a semi-permeable drainage boundary are pre- seated. Two variables are introduced to transform the two coupled governing equations of pore-water and pore-air pressures into an equivalent set of partial differential equations （PDFs）, which are easily solved by the Laplace transform method. Then, the pore-water pressure, pore-air pressure, and soil settlement are obtained in the Laplace domain. The Crump method is adopted to perform the inverse Laplace transform in order to obtain the semi-analytical solutions in the time domain. It is shown that the proposed solutions are more applicable to various types of boundary conditions and agree well with the existing solutions from the literature. Several numerical examples are provided to investigate the consolidation behavior of an unsaturated single-layer soil with single, double, mixed, and semi-permeable drainage boundaries. The changes in the pore-air and pore-water pres- sures and the soil settlement with the time factor at different values of the semi-permeable drainage boundary parameters are illustrated. In addition, parametric studies are con- ducted on the pore-air and pore-water pressures at different ratios （the air permeability coefficient to the water permeability coefficient） and depths.展开更多
This paper presents general semi-analytical solutions to Fredlund and Hasan＇s one-dimensional （1D） consolidation equations for unsaturated soils subject to different initial conditions, homogeneous boundaries and t...This paper presents general semi-analytical solutions to Fredlund and Hasan＇s one-dimensional （1D） consolidation equations for unsaturated soils subject to different initial conditions, homogeneous boundaries and time-dependent loadings. Two variables are introduced to transform the two-coupled governing equations of pore-water and poreair pressures into an equivalent set of partial differential equations （PDEs）, which are solved with the Laplace transform method. The pore-water and pore-air pressures and settlement are obtained in the Laplace transform domMn. The Crump＇s method is used to perform inverse Laplace transform to obtain the solutions in the time domain. The present solutions are more general in practical applications and show good agreement with the previous solutions in the literature.展开更多
The variation opf effective stress ratio of stratfied soil with semi-pervious boundaries and under cylic loading was analyzed on the basis of Terzaghi's one-dimensional consolidation assumptions.A solution by Lapl...The variation opf effective stress ratio of stratfied soil with semi-pervious boundaries and under cylic loading was analyzed on the basis of Terzaghi's one-dimensional consolidation assumptions.A solution by Laplace Transform was obtained for the case whe the soil was under time-varied loading.With numerical in version of Laplace Tranform.Some useful results were obtained for several kinds of commonly encountered loadings.The results can be meaningful in engineering preactice.展开更多
通过在大面积堆载场地设置监测仪器,进行历时 3 a 的现场监测,对大面积堆载作用下软土地基的变形特性和加载条件、地层条件、排水条件、时间效应等的相关性进行分析研究,揭示了大面积堆载作用下软土地基变形特性不同于常规荷载作用下软...通过在大面积堆载场地设置监测仪器,进行历时 3 a 的现场监测,对大面积堆载作用下软土地基的变形特性和加载条件、地层条件、排水条件、时间效应等的相关性进行分析研究,揭示了大面积堆载作用下软土地基变形特性不同于常规荷载作用下软土地基变形特性的规律,总结了在不同边界条件下软土地基变形和固结沉降的规律,为软土地基的固结沉降分析计算提供依据。展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.41630633 and11672172)
文摘The semi-analytical solutions to Fredlund and Hasan＇s one-dimensional （1D） consolidation for unsaturated soils with a semi-permeable drainage boundary are pre- seated. Two variables are introduced to transform the two coupled governing equations of pore-water and pore-air pressures into an equivalent set of partial differential equations （PDFs）, which are easily solved by the Laplace transform method. Then, the pore-water pressure, pore-air pressure, and soil settlement are obtained in the Laplace domain. The Crump method is adopted to perform the inverse Laplace transform in order to obtain the semi-analytical solutions in the time domain. It is shown that the proposed solutions are more applicable to various types of boundary conditions and agree well with the existing solutions from the literature. Several numerical examples are provided to investigate the consolidation behavior of an unsaturated single-layer soil with single, double, mixed, and semi-permeable drainage boundaries. The changes in the pore-air and pore-water pres- sures and the soil settlement with the time factor at different values of the semi-permeable drainage boundary parameters are illustrated. In addition, parametric studies are con- ducted on the pore-air and pore-water pressures at different ratios （the air permeability coefficient to the water permeability coefficient） and depths.
基金Project supported by the National Natural Science Foundation of China(Nos.41372279 and41630633)
文摘This paper presents general semi-analytical solutions to Fredlund and Hasan＇s one-dimensional （1D） consolidation equations for unsaturated soils subject to different initial conditions, homogeneous boundaries and time-dependent loadings. Two variables are introduced to transform the two-coupled governing equations of pore-water and poreair pressures into an equivalent set of partial differential equations （PDEs）, which are solved with the Laplace transform method. The pore-water and pore-air pressures and settlement are obtained in the Laplace transform domMn. The Crump＇s method is used to perform inverse Laplace transform to obtain the solutions in the time domain. The present solutions are more general in practical applications and show good agreement with the previous solutions in the literature.
文摘The variation opf effective stress ratio of stratfied soil with semi-pervious boundaries and under cylic loading was analyzed on the basis of Terzaghi's one-dimensional consolidation assumptions.A solution by Laplace Transform was obtained for the case whe the soil was under time-varied loading.With numerical in version of Laplace Tranform.Some useful results were obtained for several kinds of commonly encountered loadings.The results can be meaningful in engineering preactice.
文摘通过在大面积堆载场地设置监测仪器,进行历时 3 a 的现场监测,对大面积堆载作用下软土地基的变形特性和加载条件、地层条件、排水条件、时间效应等的相关性进行分析研究,揭示了大面积堆载作用下软土地基变形特性不同于常规荷载作用下软土地基变形特性的规律,总结了在不同边界条件下软土地基变形和固结沉降的规律,为软土地基的固结沉降分析计算提供依据。
