A simple method is described for obtaining the observed displacements during incremental construction of an embankment from the 'single-lift' displacements given by conventional elastic theory. This method requires no specialized techniques or computational methods. A number of solutions are presented for the displacements and stresses within a homogeneous embankment resting on a rough rigid base, and the application of these solutions to practical problems involving non-homogeneous embankments and consolidation movements is discussed. For a rockfill embankment comparisons between predicted settlements, observed values and values predicted from a finite element analysis suggest that the proposed simple method is useful for obtaining rapid estimates of embankment deformations.

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A general theory for the three-dimensional deformation of porous materials is presented to formulate a boundary value problem. The theory deals with a two-phase material consisting of viscoelastic skeleton and incompressible water. The effective stress-strain relationship of the viscoelastic skeleton is assumed to follow the linear theory of viscoelasticity developed by Gurtin and Sternberg which is based on the Stieltjes convolution.In the latter half of this paper, the triaxial compression creep test is analyzed as a boundary value problem. In the triaxial compression creep test a cylindrical sample is used which is subjected to the radial and axial compressive stresses under drained conditions. Drainage from a sample takes place only at its cylindrical wall and not on its ends. Under these conditions, the solution is obtained through the Laplace transformation. The deformation and the effective stress in a sample are obtained by applying the inverse Laplace trasformation. The solution reveals that the deformation of a sample is composed of two parts, one is the immediate change which is caused by the deviator stress, the other is the time dependent change which is caused by the mean effective stress.

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Based on detailed observations by using a microscope and thin section method, a new granular model has been proposed as a basis of theoretical considerations on granular mechanics.The specimen deformed to residual stress state can be divided into three subdomains having each homogeneous fabric, i.e., dead domain, dilated domain and shear domain. The void ratio in the dilated domain becomes equal to 20% relative density at peak stress state whose value represents an unstable particle configuration in a granular material. Concentration of directions (N_i) perpendicular to tangential planes at contacts to the maximum principal stress direction performs an essential role in strengthening granular fabric up to the peak stress state. Relative movements between particles in the shear domain occur principally by preferred sliding along the contacts having N_i inclined to σ₁-direction about 35°, and partially by rolling of each grain to reorient preferred dimensional orientation. Mobilized stress ratio of granular materials when subjected to a deviatoric stress state is found to depend not only upon the interparticle friction angle between grains φ_μ but also upon the parameter representing fabric anisotropy S_z/S_x. Experiments on two kinds of sand show that theoretical equation is closely obeyed by experimental results throughout deformation to failure irrespective of their initial void ratio and initial fabric.

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An electro hydraulic servo type loading system was incorporated into the conventional triaxial shear test apparatus so that any desired form of load pattern can be applied to soil specimens. In applying this system to the study of liquefaction of saturated sands, a difficulty was encountered in keeping the applied stress perfectly controlled even after the rigidity of the sample falls considerably due to the onset of liquefaction. The use of an elastic joint in the loading ram proved very useful to overcome this defect. The acceleration records obtained at the time of the Niigata earthquake of 1964 were used as input load patterns to be applied to saturated specimens of a Niigata sand. The investigation disclosed several features of interest concerning the behaviors of the sand when subjected to irregular exitation.

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